Construction Health and Safety Manual: Ironworkers - IHSA · - Site preparation and steel erection...
Transcript of Construction Health and Safety Manual: Ironworkers - IHSA · - Site preparation and steel erection...
38 – 1
38 IRONWORKERS:STRUCTURAL STEEL
Contents- Personal protective equipment (PPE)
- Cold stress and heat stress
- Lead exposure
- Tools of the trade
- Site preparation and steel erection
- Safe access and fall protection
- Mobile welding rigs
Personal protectiveequipment (PPE)Clothing: Many injuries can be prevented bychoosing the right clothing. Don’t have cuffs onyour pants or sleeves because they can getcaught on something and cause you to fall.Cuffs can also catch sparks and cause a burn.
Hearing protection: Hearing protection is amust for today’s ironworker. Hammering,reaming, and equipment all produce noise atlevels that can harm your hearing. Wearappropriate hearing protection. It should filterout noise above 85 decibels but still allow youto communicate with your co-workers and hearany alarms or warnings. Reduce the risk ofinfection: Make sure that your hands are cleanbefore using expanding foam hearingprotection.
Eye protection: Wear proper eye protectionwhen reaming drilling, grinding, burning,welding—or whenever hazards require it. Theright eye protection can be different for differentactivities. For example, it’s common forironworkers to perform activities such as gascutting and stud welding. These activities wouldrequire the use of Class 2C goggles for radiationprotection. It is also common for ironworkers tobe grinding and cutting. These activities would
require the use of a full face shield to reduce therisk of injury from flying objects and particles. Atsome jobsites, eye protection is mandatory.Always wear eye protection as required. Forfurther information, refer to the chapter on PPEin this manual for a list of activities withrecommended eye and face protection.
Skin protection: Ironworkers must protecttheir skin against burns from hot metal,ultraviolet (UV) radiation from the sun, weldingradiation, and other hazards. Skin protectionincludes
• clothing that is flame-resistant and providesUV protection
• long sleeved shirts
• full-length pants
• leather-faced gloves
• sunscreen with a sun protection factor(SPF) of 15 or higher.
Leather-faced gloves provide protection fromhot steel and resistance to abrasion.
Head protection: A hard hat complying withthe Construction Regulation (Ontario Regulation213/91) is required on construction projects at
IRONWORKERS: STRUCTURAL STEEL
Figure 1. Ironworkers at work
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all times. A CSA Type 2 Class E or equivalenthat with chinstrap is recommended becauseironworkers
• work at elevations in windy conditions
• have increased risk of a lateral impact dueto the specific nature of their work.
Please note that hard hats must be worn withthe brim forward unless the hat has been testedand the manufacturer confirms that it can beworn with the brim pointing backwards. (Thehard hat will have an embossed symbolindicating that it has been certified as safe to beworn backwards.)
Foot protection: Workers must wear CSAcertified Grade 1 boots. Boots should also beresistant to electric shock (certified by a whitelabel with the Greek letter omega Ω).Ironworkers should wear boots with slipresistant soles because of the time spentwalking on smooth beams.
Hand protection: Gloves are an essential partof everyday PPE. Select your gloves based onsite conditions such as temperature, the workbeing performed, the chance of getting cuts andabrasions, and the dexterity required.
For more information, see the chapter on PPE inthis manual.
Cold Stress andHeat StressCold Stress
Working in cold environments presents healthrisks. The cold can be caused naturally by theweather or be created artificially, as inrefrigerated environments. You can get seriouscold-related illnesses and injuries, leading topermanent tissue damage and even death.
Exposure to cold causes two major healthproblems: hypothermia and frostbite.
For more information, see the chapter on ColdStress in this manual.
Heat Stress
Heat stress can occur wherever constructionoperations take place in hot, humidenvironments. The locations may be indoors oroutdoors.
Works that requires you to wear semi-permeableor impermeable protective clothing cancontribute significantly to heat stress. Heat stresscauses the body's core temperature to rise andcould lead to confusion, irrational behaviour,loss of consciousness and even death.
For further information please see the chapteron Heat Stress in this manual.
Lead exposureThis section supplements the chapter onOccupational Health in this manual withmaterial of particular importance to ironworkers.
The fumes from welding and cutting are thegreatest health hazards for ironworkers.Exposure to welding by-products such as fumes,radiation, noise, or vibration is covered in thechapter on Occupational Health. The risk toyour health is worse when there is a lead-basedpaint on the metal being cut or welded.
The following sections deal with the hazard oflead exposure during welding and cuttingprocesses. For further information refer to theMinistry of Labour’s guideline Lead onConstruction Projects. We have excerpted achart from that guideline at the end of thissection.
HOW CAN I GET LEAD POISONING?Lead poisoning can occur when you inhale oringest lead dust and fumes during burning orwelding of steel structures coated with lead-containing paints.
WHAT ARE THE HEALTH EFFECTS?Common symptoms of acute lead poisoning areloss of appetite, nausea, vomiting, stomachcramps, constipation, difficulty in sleeping,
IRONWORKERS: STRUCTURAL STEEL
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fatigue, moodiness, headache, joint or muscleaches, anaemia, and decreased sexual drive.Severe health effects include damage to thenervous system, including wrist or foot drop,tremors, and convulsions or seizures.
The frequency and severity of medicalsymptoms increase with the concentration oflead in the blood.
Chronic lead poisoning may result after lead hasaccumulated in the body over time, mostly inthe bone. Long after exposure has ceased, somephysiological event such as illness or pregnancymay release this stored lead from the bone andproduce health problems such as impairedblood synthesis, alteration in the nervoussystem, high blood pressure, effects on maleand female reproductive systems, and damageto the developing fetus.
APPLICABLE REGULATIONSRegarding regulations governing lead exposureon construction projects, the Ministry of Labourreferences Designated Substances—Lead(Regulation 843) and makes it relevant forconstruction projects with section 25(2)(h) ofthe Occupational Health and Safety Act, Thefollowing excerpt regarding lead exposure wastaken from the Ministry of Labour’s guidelineLead on Construction Projects:
“The Ministry’s designated substance regulation(DSR) for lead, Regulation 843, specifiesoccupational exposure limits (OELs) for lead,and requires assessment and a control programto ensure compliance with these OELs. The OELfor inorganic lead is 0.05 milligrams per cubicmetre (mg/m3) of air as an 8-hour daily or40-hour weekly time-weighted average.”
“Measures and procedures that ensureconstruction workers receive the same standardof protection as workers covered by Regulation843 should therefore be implemented onconstruction projects where exposure to lead isa hazard. Such measures and procedures aredeemed to be in compliance with section25(2)(h) of the OHS, as taking “every precaution
reasonable in the circumstances for theprotection of a worker.”
WELDING, CUTTING, OR BURNINGBefore welding, cutting, or burning any metalcoated with lead-containing materials, removethe coating to a point at least four inches fromthe area where heat will be applied. Whenremoval of lead-containing paint is not feasible,use engineering controls (e.g., local exhaustventilation) to protect workers. The controls
should remove fumes and smoke at the sourceand keep the concentration of lead in thebreathing zone below the exposure limit.
REMOVAL OF LEAD PAINTLead-based paint can be removed by a varietyof methods, including
• chemical stripping (do not use chlorinatedsolvents for stripping paint because theycan lead to toxic fumes being producedduring welding)
• wet scraping using a paint scraper
• mechanical stripping if the sander orgrinder is equipped with a High EfficiencyParticulate Air (HEPA) filter.
• heat stripping if the temperature is below600°C. Above 600°C lead fumes becomeairborne creating a significant inhalationhazard.
IRONWORKERS: STRUCTURAL STEEL
Figure 2. Portable fume extractor
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Use protective sheeting to collect debris that hasbeen sanded, grinded, or stripped away.
Do not do any of the following activities whenworking in areas that might contain lead-basedpaint because they can create dangerous levelsof lead dust or fumes.
• Open flame burning or torching (includingpropane-fuelled heat grids) and heat gunsoperating above 600°C. These activitiesrelease toxic fumes.
• Machine sanding or grinding without aHEPA filter. These activities create leaddust.
• Uncontained hydroblasting, high-pressurewashing or abrasive blasting, or sandblasting.These activities create lead dust.
• Using methylene chloride paint removalproducts. These products release toxicfumes.
• Extensive dry scraping creates lead dust.
PERSONAL HYGIENEPersonal hygiene is an important element of anyprogram for protecting ironworkers fromexposure to lead dust. Employers should provideadequate washing facilities at the jobsite so thatworkers can remove lead particles thataccumulate on the skin and hair. For certain high-hazard operations, decontamination facilities withshowers may be required.
All workers exposed to lead should wash theirhands and faces before eating, drinking, orsmoking, and they should not eat, drink, or usetobacco products in the work area. Tobaccoproducts (cigarettes, cigars, chewing tobacco,etc.) and food items should not be permitted inthe work area. Contaminated work clothesshould be removed before eating.
Workers should change into work clothes at thejobsite. Work clothes include disposable orwashable coveralls. Street clothes should bestored separately from work clothes in a clean
area provided by the employer. Separate lockersor storage facilities should be provided so thatwork clothing and shoes do not contaminateclean clothing.
Workers should change back into their streetclothes after washing or showering and beforeleaving the jobsite. Doing so will prevent theaccumulation of lead dust in workers' cars andhomes and protect their family members fromexposure to lead. Separate laundering ofwashable coveralls can help prevent take-homeexposures.
WARNING SIGNSPost warning signs to mark the boundaries oflead-contaminated work areas. These signsshould indicate that there is a lead hazard andprohibit eating and drinking in the area.
PERSONAL PROTECTIVE EQUIPMENT(PPE)Use engineering controls and good workpractices to minimize worker exposure to lead.PPE should supplement the engineering controlsand good work practices.
PROTECTIVE CLOTHINGWorkers who are welding, cutting, or burningshould wear non-flammable clothing.
Protective clothing not only shields workersfrom the hazards of welding, but it alsominimizes the accumulation of lead on theworkers’ skin and hair. Workers should changeinto washable coveralls or disposable clothingbefore entering the contaminated work area.
Wearing protective equipment or clothing cancontribute to the development of heat stress.Take steps to prevent heat stress. See thechapter on Heat Stress in this manual.
To reduce the amount of lead that couldaccumulate in a worker’s car and home, and toprotect the members of the worker's household,lead-contaminated clothing (includingworkboots) should be left at the jobsite.
IRONWORKERS: STRUCTURAL STEEL
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RESPIRATORY PROTECTIONThe best way to minimize worker exposure tolead is “control at the source” (such ascontainment or local exhaust ventilation).Control at the source, however, is oftenimpractical at construction sites, where airbornelead concentrations may be high or may varyunpredictably. Therefore, respiratory protectionis also necessary for operations such as sandingor grinding. A respirator is the last resort, butsometimes it’s your only choice.
When respirators are used, the employer mustestablish a comprehensive respiratory protectionprogram as outlined in the CSA standard Z94.4-93: Selection, Use, and Care of Respirators.Important elements of the CSA standard are:
• an evaluation of the worker's ability toperform the work while wearing arespirator
• regular training of personnel
• periodic environmental monitoring, and
• respirator fit testing, maintenance,inspection, cleaning, and storage.
The employer should evaluate the respiratoryprotection program regularly.
Respirators should be selected by the person who
• is in charge of the program
• is familiar with the workplace
• knows about the limitations of each typeof respirator.
The amount of lead released during constructionand can vary substantially, so use the highestanticipated exposure to determine theappropriate respirator for each job.
Respirator selection should be made accordingto the guidelines in the table below, which is anexcerpt from the Ministry of Labour’s guidelineLead on Construction Projects. Employers mustuse respirators that are approved by the
National Institute of Occupational Safety andHealth (NIOSH).
Medical Monitoring
The level of lead in the blood is currently thebest indicator of a person’s exposure to lead.Workers who can potentially be exposed to leadshould be monitored for the presence of lead intheir blood and for any effects of lead on theblood-forming system. This assessment isnecessary to ensure that engineering controls,personal hygiene practices, and PPE arepreventing lead exposure. Workers are notrequired to participate in a medical monitoringprogram if they don’t want to.
TRAININGWorkers should receive training that includes
• information about the health effects of leadexposure
• information about how to recognize leadpoisoning early
• description of proper personal hygienepractices that reduce the risk of leadpoisoning
• instruction on the use and care ofprotective equipment (including protectiveclothing and respiratory protection)
• instruction on specific practices forworking safely with lead-containing paints.
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IRONWORKERS: STRUCTURAL STEEL
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the
next
pag
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38 – 7
IRONWORKERS: STRUCTURAL STEEL
OP
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AT
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next
pag
e
38 – 8
IRONWORKERS: STRUCTURAL STEEL
OP
ER
AT
ION
SR
EQ
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RE
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AT
OR
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SUR
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38 – 9
Tools of the TradeHand Tools
Ironworkers normally carry their hand tools ontheir belt or in a pouch on their belt. Load yourbelt so that it does not hinder your movements.Balance the tools on the belt so one side is notloaded more than the other. Place commonlyused tools such as a spud wrench on yourdominant side, i.e., on your right if you areright-handed. Don’t carry tools by slipping themunder your belt and make sure that your toolsare secure and cannot fall.
Regularly inspect all hand tools for:
• split or loose handles
• mushroomed heads
• sprung parts.
Stop using unsafe tools immediately and tagthem to identify the defects. Turn them in forrepair or replace them.
Don’t leave tools on ledges, ladders, beams, ornear the edges of scaffolds or other worksurfaces where they can be knocked off orwhere workers can trip over them. Store tools inappropriate containers away from edges.
Don’t carry anything in your hands while usinga ladder. Use hand lines for lifting tools orequipment.
Wrenches
When working with a wrench, there is alwaysthe hazard that it can slip off the work, or thatthe object may suddenly turn free. There is alsothe chance that the wrench or bolt will break.Always brace yourself so you won’t lose yourbalance or be injured. Inspect your wrenchesfor flaws that could cause them to slip.
The spud wrench is the ironworker’s mostcommon wrench. It should have a roundtapered handle forged at an angle to provideample clearance for the hand yet keep the headin proper position for maximum power. The
tapered end is used for aligning bolt holes inadjacent members. Spud wrenches are availablein different sizes, so it is important to know thesize of bolt being used before beginning work.Don’t use a shim to make a wrench fit.
• Always grip the wrench so you won’t beinjured if it slips.
• Discard any damaged box or open-endwrench.
• Don't try to repair a wrench with roundedor damaged points on the box end, orworn or spread jaws on the open end.
• Wrenches are made from tempered steeland should not be welded.
• Face an adjustable wrench forward andturn the wrench so pressure is against thepermanent jaw.
• Always pull on a wrench toward yourtorso, this will reduce the chance of fingerinjuries if the wrench slips.
• Handle stops on channel locks or plierswill prevent pinching injuries to the handand fingers.
• Never overload a wrench by using a pipeextension on the handle or by striking thehandle with a hammer. This can weakenthe metal of the wrench and cause the toolto break. Heavy-duty box wrenches withextra long handles and "hammer" orstriking-face wrenches are available forthese jobs. The striking-face wrenches with
IRONWORKERS: STRUCTURAL STEEL
Figure 3. SpudWrench
38 – 10
12-point box openings are designed forstriking with a ballpeen or sledge hammer.Both offset and straight styles are availablebut the straight type is safer.
Socket Wrenches
Socket wrench sets offer a multitude of optionsin both the types and sizes of the sockets, andthe variety of drivers available for themincluding ratchet, universal, speeder, and theirmany extensions and adapters. When usingadapters and adapting down in size, be carefulnot to over-torque a smaller socket and fastenerwith a larger driver.
Always use the correct size of socket; make sureit fits snugly. An oversized or sloppy fit can leadthe wrench to slip and injure you, as well ascausing wear to both the socket and the fastener.
Never use "hand" sockets on a power drive orimpact wrench. (Hand sockets normally have abright finish, while power and impact socketsusually have a dull finish and usually havethicker walls.)
Hickey Bars
Hickey bars are used to position steel forconnection, or while shaking out or sortingsteel. They provide the extra leverage requiredfor a worker to move steel members which areheavy and awkward. When using a hickey bar,
• inspect it before using it
• position your feet and body so that youwon’t lose your balance
• avoid pinch points
• ensure that there is enough clearance forthe member to move
• stand to the side and turn the beam awayfrom you.
Drift Pins and Punches
A drift pin is a tool tapered at one or both endswhich is used to align holes before connecting.When striking drift pins, wedges, punches, orchisels with a hammer, hold them with tongs toprevent injuries to hands. Bull pins are taperedat one end with a striking head on the other.Using this type of drift pin reduces the chancesof hand injury.
Don’t use the tool if a mushroom headdevelops. If you hit a mushroom head, particlescan fly off.
Power tools
• Inspect and maintain power tools on aregular basis. Repair or discard defectivetools.
• Power tools should have a “dead man”trigger or switch to prevent accidentalactivation.
IRONWORKERS: STRUCTURAL STEEL
Figure 4. Correct use of adjustable wrench
Moveable Jaw
Direction of Pull
Figure 5 Hickey bars or beam turners
Figure 6: Bull Pin Figure 7: Reamer Figure 8: Drift Pin
38 – 11
• All portable electric hand tools must begrounded or double-insulated. The groundwires must be continuous from the toolhousing to the power-source ground. Makesure that the casing on double-insulatedtools are not cracked or broken.
• Use only those electric hand tools bearingCanadian Standards Association (CSA)approval.
• Safety guards should be kept in place ongrinders and other power tools.
• Do not use a rotary screw with aprotruding set screw that can catch ongloves or clothing.
• Use proper pins and o-rings to securesockets to impact wrenches. Do not relyon rods, wire, or other makeshift materials.
• To thaw pneumatic tools place them in awarm area. Do not use direct heat. Properuse of a de-icer will keep pneumatic toolsfrom freezing.
• All moving parts need to be guarded toprevent loose clothing or hair frombecoming entangled in them.
• Use only the right tool for the job.
Gas- or Diesel-Driven Equipment
• Do nor refuel or lubricate an engine whileit is running. Stop the motor and allow itto cool. Plan to refuel equipment first thingin the morning or at the beginning of theshift.
• Do not refuel while welding or burning istaking place in the area. Hot slag canbounce over a wide area.
• When using cold-weather starting fluids,such as ether, take extra care and followthe manufacturer’s instructions. Too muchether can damage the engine.
• If a gasoline line or any part of an enginefreezes, do not use a torch to thaw it out.
Use gas-line antifreeze or a heating pad, orwrap the frozen part in a cloth and pourhot water over it. In sub-zero weather, skincontact with gasoline increases the risk offrostbite. Protect your hands from contactwith gasoline or similar fluids.
• Provide proper ventilation if you’reoperating engines in an enclosed orunventilated area.
• At the start and end of each shift—and atleast once during the day—bleedcompressors (release air from thechamber) to blow off any condensationthat has collected.
• Check to ensure that all gauges areworking properly and report anymalfunction.
• Use only non-flammable solvents to cleanan engine.
Propane-driven equipment: Follow themanufacturer’s instructions for checkingregulators, fittings, cylinders, and othercomponents. Only workers who have receivedtraining in handling propane are allowed tohandle propane bottles or equipment. Forpropane training, contact the Construction SafetyAssociation of Ontario or other certified trainers.
Electrically Driven Equipment
Wired electrical connections must be made byonly qualified electricians and must conform toall applicable regulations.
Assume that all wires and switches areenergized until proper inspection can proveotherwise.
When working on or near electrically drivenequipment, follow appropriate lock-outprocedures. Turn off the equipment, then closedown and lock the switch box. See the chapteron Lockout and Tag in this manual for moreinformation on procedures.
IRONWORKERS: STRUCTURAL STEEL
38 – 12
On grounded electrical machines or motors, theground wire should be continuous from thehousing to the power source.
Only explosion-proof motors and switchesshould be used in locations where ignition cancause a fire or explosion.
Site Preparation andSteel ErectionHoisting Equipment
Cranes are used primarily to hoist steel intoposition. The crane operator must have thecorrect licence for the type of crane beingoperated and be familiar with the crane.
See the chapter on Rigging in this manual forcomplete information on rigging.
Before any steel structure can be erected safelyand efficiently, the sequence of erection must beplanned in advance and the structural memberslaid out in the order of their erection. Workareas for cutting should be laid out in advanceto ensure safe and efficient operation. Whenstockpiling steel for on-site fabrication, ensurethat a good solid base is provided for storage. Ifthe steel is to be piled high, use long sleepers toensure a level and safe storage area.
Keep work areas clear of clutter, debris, andscrap material. Keep a box or barrel close by forthe disposal of scrap.
Preparing On-Site Storage Areas
The area where the material is to be storedshould be as level as possible, well-drained and
with good access. Storage areas should be asclose to the work area as possible. Storage areasshould be well laid-out with clear and directaccess to work areas. Store the material so that itwill be kept free from mud, oil, grease, etc. Ingeneral, a clean work area is a safe work area.Store materials away from travelled walkways.
Avoid storing materials under powerlines,especially if using hoisting equipment to move it.
4x4 sleepers should be used to keep the steeloff the ground and to allow slings to pass freelyunder the load. Make sure there is adequateblocking available before steel is delivered.
The general contractor should be consultedbefore setting up storage areas so that thegeneral is aware of potential weights to bestored in each area. Ensure that steel stored onfloors does not overload the structure, and thatreshoring is in place if necessary.
Material should be stored at least 1.8 metres (6feet) away from all slab edges and openings.
Normally, members are laid down on site andsorted after they arrive. Plan the job well so thatmembers can be laid out in sequence. This willavoid moving the steel repeatedly.
Unloading and Storage Precautions
Post “DANGER” signs and cordon offunloading areas as required. Always keeppeople who are not directly involved with off-loading out of the area.
Be sure to communicate with the driver aboutunloading procedures.
Serious accidents can occur if tie-downs arereleased without the load being contained toprevent materials from spilling over. It is veryimportant to check if the load has shifted beforeyou off-load it. If it has shifted, the weight onthe trailer may not be evenly distributed and thestraps may be over-tensioned. Many workershave been struck by shipping straps uponrelease.
IRONWORKERS: STRUCTURAL STEEL
Figure 9: Grinder Figure 10: Impact Gun
38 – 13
When unloading the trailer always watch forloose or small pieces. Sometimes, steel suppliersor delivery companies place small pieces eitheron or in-between larger pieces. These smallpieces can cause serious injury if they shift orfall while being lifted. Always walk to the endsafter hooking up and examine the blocking thatwas used. Blocking should be hardwood, but itcould be something else. Don’t assume that thesupplier’s delivery company has used hardwoodwhen loading the trailer.
Land and block the load before unhooking it.Lower loads onto adequate blocking to preventdamage to slings.
Make sure identification marks are clearly visibleto avoid extra handling.
Space the members so that they can be pickedin sequence without having to move othermembers. If members must be stacked in layers,put sleepers between each layer.
Near openings, arrange material so that itcannot roll or slide in the direction of theopening.
Positioning the Truck
• The truck should be positioned on a levelarea as close to the crane as possible toprevent the crane from overreaching.
• Keep the truck and crane away fromoverhead powerlines.
• Trucks backing up must be directed by acompetent signaller.
• The supervisor should tell the truck driverwhere to wait during loading andunloading.
• Always stake loads before unloading.
• Unload the truck in such a way to preventuneven weight distribution. Uneven loaddistribution could cause the truck bed toshift, resulting in material spill over.
High-Visibility Clothing
The Construction Regulation (Ontario Regulation213/91) requires that any worker who may beendangered by vehicles on a project must wearhigh-visibility clothing.
IRONWORKERS: STRUCTURAL STEEL
Figure 11. Picture of steel laid out
Timber Blocking
Timber
Timber Blocking
Method ofPiling Beams
Methodof Piling
Channels
Methodof PilingAngles
Methodof PilingPlates
Figure 12. Hand Signals for Traffic Control
Back up
Clearance
Stop
Change direction
38 – 14
Unless stated otherwise, the high-visibilityclothing described in this section applies tosignallers and workers directing traffic.
High-visibility clothing has two main
features:
• Background material — The fabricmust be fluorescent orange or brightorange and provide the wearer withincreased daytime visibility. Werecommend fluorescent orange because itprovides a higher level of daytimevisibility.
• Retroreflective stripes or bands —The stripes or bands must be
- yellow, fluorescent, and retroreflective
- arranged in two vertical stripes downthe front, and in an “X” on the back
- 50 mm wide
These retroreflective stripes give the workerboth low-light and nighttime visibility. For nightwork, you also need stripes or bands on thearms and legs. One way to meet thisrequirement is to dress workers in fluorescentorange coveralls with retroreflective bands orstripes attached.
Risk Assessment
Before selecting high-visibility clothes, assess therisks you need to control. Workers who needgreater visibility, such as roadway constructionworkers, should wear clothing that is verynoticeable under the conditions expected.
For further recommendations on high-visibilityclothing, consult CSA standard Z96-02.
Mounting and Dismounting Truck Beds
Many accidents have occurred as the result ofworkers getting on or off a flatbed truck.
• Before getting on the truck, clean off yourboot soles to avoid slips.
• Mount the truck platform in full view ofthe crane operator or signaller. This will
prevent you from being struck by the loador the crane hook.
• Climb up and down facing the truck,maintaining 3-point contact at all times(two hands and one foot, or two feet andone hand on the trailer).
• If steps and handrails are provided, usethem. Tires or hubs don’t give you stablefooting.
Safe Rigging and Slinging
There are times when workers who are notprofessional riggers must rig loads. Ironworkersare often involved, not only in handling, but inhoisting and receiving material. When in doubtabout rigging consult an experienced rigger or aprofessional engineer. Information in this sectioncan only provide the basics of rigging. Moreinformation is contained in the Rigging chapterof this manual or the Hoisting and RiggingSafety Manual (M035) published by theConstruction Safety Association of Ontario.
Safe rigging basically depends on knowing
• the weight of the load to be lifted
• the capacity of the hoisting device
• the safe working loads of ropes andhardware.
MAJOR HAZARDSThe most frequent cause of rigging accidents islack of knowledge. In rigging, experience is notnecessarily the same thing as knowledge. Sinceironwork involves a lot of materials handling,the methods and equipment used to rig, lift, andmove materials are important for the trade.
Overhead powerlines — Most lifting devicesand all wire rope hoist lines and slings areexcellent conductors of electricity. No part of alifting device or its load must come closer thanone boom length to a live overhead powerline,unless a signaller directs the operator. No partof a lifting device or its load must come closerto live powerlines than the minimum distances
IRONWORKERS: STRUCTURAL STEEL
38 – 15
listed in the table below unless the powerlinehas been insulated by the owner of thepowerline and procedures are in place toprotect the workers from electrical shock.
Voltage Rating of Powerline Minimum Distance
750 or more volts, but not 3 metres (10')more than 150,000 volts
more than 150,000 but 4.5 metres (15')not more than 250,000 volts
more than 250,000 volts 6 metres (20')
Load too heavy for rigging equipment orrigging arrangement — This problem maybe related to
• planning
• the selection, condition, and inspection ofequipment
• improper estimates of the load to bemoved or lifted.
Weather — Weather conditions such as rainand ice can affect the rigging, control, andhandling of loads as well as the lifting devicesinvolved. Visibility and wind can also createproblems in hoisting and landing loads.
Unexpected loads – Loads can suddenlymove or slip because of
• weather conditions
• travel or swing that is too fast or abrupt
• inadequate support under lifting devices
• unexpected drifting.
These and other conditions can create additionalloads on rigging components, and lead to failureor collapse.
Inadequate components — Slings, shackles,hooks, and other equipment must be in goodcondition and properly sized, configured, andload-rated for the job.
Failure to keep hoist lines vertical —When hoist lines are not vertical, loads canswing unexpectedly. In particular, loads that
must be drifted into position can pull lines outof vertical. The load may slip, come apart, andstrike workers or the lifting device.
Toppling, shifting, or falling material —These problems can be caused by
• improper use of slings
• using slings not suited to the size, weight,and shape of the load
• inadequate attachment of load to liftingdevice.
Loads must be secure before, during, and afterthe lift. Pipe, in particular, is very likely to shiftor roll unless properly secured. The criticalmoment often comes when the hoist line istensioned up or slacked off. That's whenworkers should stand clear.
Lifting overhead — The dangers of standingdirectly under a load being lifted or lowered areobvious. Although it is sometimes difficult to doon crowded construction sites, workers andoperators should avoid situations where loadsare hoisted over people. Connectors must beextra diligent when they are receiving loads.
Inadequate landing surface — Loads mustsometimes be lifted to scaffolding, plankedplatforms, or other temporary structures. Thesesurfaces must be able to support whatever loadsare applied. In some cases, a knowledgeableperson may have to assess the load-carryingcapacity of the temporary structure.
Determining Load Weights
The most important step in any riggingoperation is determining the weight of the loadto be hoisted. If this information cannot beobtained from shipping papers, design plans,catalogue data, or other dependable sources, itmay be necessary to calculate the weight. Moststructural steel is classified by size and weight.For example, a W310 x 79 beam means that thebeam is 310 mm deep and 79 kg per linearmetre. Therefore a beam of this size that is 10metres long weighs 790 kg. Remember: The
IRONWORKERS: STRUCTURAL STEEL
38 – 16
weight of all rigging equipment must beincluded as part of the load to be lifted.
The time taken to calculate the approximateweight of any load is time well spent. It mayprevent a serious accident from a failure oflifting gear or crane collapse.
Inspection
It is important to inspect rigging, before eachuse, for damage or excessive wear. The capacityof a worn or damaged fibre rope, metal sling, orsynthetic sling can be greatly diminished,making them unsafe to use. More information iscontained in the Rigging chapter of this manual,and in the Hoisting and Rigging Safety Manual(M035) published by the Construction SafetyAssociation of Ontario.
MULTIPLE LIFTS (TIERED LIFTS)Multi-tiered lifts may be performed under certainconditions to hoist structural members intoposition. This method can reduce the potentialfor some accidents by reducing the number oftimes the crane must swing when loaded.However, the practice is highly specialized andmust be carried out only by trained workers,using established procedures and dedicatedrigging assemblies.
Inspection and capacity requirements for
rigging equipment
Before hoisting any structural members, therigging equipment must be inspected by acompetent worker at the beginning of eachshift. Removal criteria must be established. Ifthere is any doubt about the integrity of therigging components, the component in questionmust be replaced. Remember, the rigging mustbe able to support the total load attached to it,not just individual beams.
The following conditions must be met to safelyhoist multiple lifts.
• A complete inspection of all riggingequipment must be carried out daily.
• An engineered, dedicated, multiple-riggingassembly must be used. This assembly isnot to be used for other hoistingoperations.
• All hooks must have safety catches.
• Only workers directly involved in hookingon the steel, or connectors who arereceiving the loads, can be involved.
• Three members is the maximum that canbe hoisted at any time.
IRONWORKERS: STRUCTURAL STEEL
Fig. 13. Rigging assembly with 3 chokers of different lengths.
Fig. 14. Three beams hanging in an assembly
38 – 17
• The members must be aligned so that aminimum clear distance of 2.1 metresexists between rigged members. This givesclearance so workers hooking up orconnecting will not be struck by membersoverhead.
• Members are to be connected with a tagline at one end in order to prevent rotation.
• All workers involved in the process,including the crane operator, must betrained in the specific procedure beingused. Records of training including namesof workers and their responsibilities mustbe kept on site.
• Only structural members can be lifted.Bundled loads cannot be lifted.
• Routes for suspended loads must be pre-planned to ensure the load does not passover other workers.
• A copy of the engineered liftingprocedures and any alterations to theprocedures must be kept on site.
• Before any multiple lifts, the nearestMinistry of Labour office must be notified.
Methods of rigging multiple loads
There are several methods of rigging multipleloads. One method is to use chokers of differentlengths as shown in Figure 13. Another methodis to string chokers end-to-end with membersattached by slings to the chokers. Thesemethods are acceptable if they have beendesigned by a professional engineer.
CHOOSING THE HARDWAREKnow the safe working loads of slings andrigging hardware. Never exceed the limit of theweakest device.
Rigging equipment must be inspected beforeuse. If you have any doubt about a piece ofequipment, change it, or consult with somebodymore experienced in rigging.
Workers involved in offloading steel must becompetent through training and experience.When staking is required, stake the load beforereleasing binders.
Softener such as wood or split pipe should beused on the sharp edges of a load to protect thesling from being cut. Secure the softeners to thesling to prevent them falling off.
Keep your hands away from the load and slingswhile the load is being lifted.
Use tag lines to guide suspended loads. Coil theends of tag lines to prevent snagging ortripping. Do not stand in the coils of a tag lineor wrap a tag line around your hand.
Do not take hold of the hoist cable close to asheave or block. Your hand may be drawn in tothe block.
Do not climb on to a vehicle or crane while it ismoving or operating.
Before lifting the load make sure that it is clearof other material or obstructions.
Hooking On
• Normally two workers are involved in thehooking-on process.
• Rig the steel so that it will not shift duringhoisting yet it will be relatively easy tounhook.
• Do not stand under a load or boom.
• Keep your eyes on the entire load as it isbeing hoisted to ensure that nothing shifts.
Hooking on multiple lifts (tiered lifts)
• Workers hooking on the steel must knowthe sequence of connecting so that the firstmember to be connected is the lastmember to be hooked on.
• The centre of each piece should be markedbefore being hooked up. When it is lifted itmust hang level. It should be raised slightlyoff the ground to ensure that it is level. If
IRONWORKERS: STRUCTURAL STEEL
38 – 18
not, it must be put down and the chokeradjusted. When rigging long members, usetwo chokers to keep the beam balanced.
• As the load is being hooked, take care toprevent the remaining hooks fromsnagging other beams.
• A tag line must be attached at one end ofeach member, connecting all the membersto be hoisted. It will ensure that themembers do not rotate independently. Thistag line can be left to hang. Workersreceiving the load can use it to guide theload into position.
Connecting
A connector is a trained ironworker who makesthe initial connection of structural steelmembers. The supervisor should designate theconnectors in the crew. There should normallybe two connectors for each crane working.
Connecting steel members comes with manyhazards. Falls are the greatest hazard becausethis work is done mainly at heights. It’s difficultto find adequate lifeline anchors, particularlybecause members are not fully connected. Seethe chapter on fall protection in this manual.
Other common injuries are being struck by steelmembers and having hands and fingers pinchedbetween members. These injuries can often leadto falls and more serious injuries. To preventthem, follow these precautions:
• Connectors must be ready for a member asit approaches. Don’t do any other work atthe time. Keep your eyes on the steel as itapproaches and guide it into position.
• Use a drift pin or wrench to match upholes. Don’t use your fingers. Manyworkers have lost fingers this way.
• Before being cut loose, the beam must bebolted so that it will not rotate. At leasttwo or more bolts should be put inposition, depending on the engineer’srequirements. Do not rely on a drift pin ora wrench placed in a hole.
• Columns, trusses, and beams that are notproperly tied-in should be guyed beforeyou cut them loose.
• When working above reinforcing steel ordowels, ensure that the ends of the rods arecovered to protect you from being impaled.
• Use extra care while working on a beamfitted with shear connectors or NelsonStuds. Grip the beam, not the studs. Tuckin or tape your pant cuffs to avoid trippingon the studs.
Connecting multiple lifts (tiered lifts)
When the beam is lowered into position, it mustbe connected with a minimum number of boltsin the usual way. After is has been unhookedfrom the crane, position the next member. Theconnectors must be aware of the overheadmembers at all times. When all the membershave been released from the crane, the riggingassembly is lifted clear by the crane. Theconnectors must ensure that the riggingassembly does not snag a piece of the structureas it is being lifted clear. These chokers caneasily trip a worker or become snagged in othermembers.
Bolting Up
The bolting up crew follows the erection crew.Their role is to install the remaining bolts ateach connection. They normally work from atemporary platform such as a scaffold, anelevating work platform, or from the steel itself.Fall protection is easier to achieve for this workbecause the structural members are secure atthis stage, or fall arrest anchors have alreadybeen installed.
Tools and equipment should be carried incontainers. Do not leave bolts, washers, driftpins, or empty bolt cans lying around on beamsor work platforms.
Do not allow air hoses or cables to clutterwalkways, platforms, or ladders where someonecould trip. When it is necessary to work with a
IRONWORKERS: STRUCTURAL STEEL
38 – 19
long lead or hose be sure that it is tied off atseveral points to prevent whipping if the hosewas cut or disconnected.
Reaming and drilling
Reaming and drilling is often necessary toproperly align holes for connection. Basicprecautions include eye and hearing protectionbecause flying particles and noise areunavoidable.
In two-person operations, workers shouldstand on the same level and coordinate theirmovements. When reaming or drillingvertically, workers should stand on oppositesides of the tool and face each other. Whenreaming or drilling horizontally, workersshould keep the tool between them, preferablyat waist level and face the material. Avoidreaming or drilling overhead as controlling theequipment is difficult. Make sure that youhave enough space, secure footing and properbalance when reaming or drilling, especiallywhen you’re above floor or ground level.
Do not use an electric reamer or drill on a steelbeam that is being welded unless the membersare grounded.
When using a magnetic base drill, secure it tothe structure in case of a power failure.
Use the right size of bit for the job. Keep the bitstraight when reaming or drilling. Take extracare with bits having two or three flutes becausethey tend to bite or stick. Make sure drill bitsare sharp and true. Bits should be reconditionedregularly by a qualified person.
When drilling a deep hole beyond the flutes ofthe bit, clean out the chips by removing andreinserting the bit several times with the poweroff. Don’t let the chips or shavings build up ina hole because the bit may become tight orjam up.
Lightweight or small pieces of steel should beclamped, bolted, or tack welded so they will notbind on the bit and whip around.
Riveting
Although riveting is no longer used extensivelyon structural steel, the following tips on saferiveting are still useful for renovations,maintenance, and demolition work and fordriving drift pins with rivet guns.
• Snaps must be wired to the riveting gunbridle.
• Remove snaps and plunger when leavingthe job for any length of time.
• The riveting gun should not be left in aposition such that the trigger could bereleased unintentionally.
• When cutting or backing out rivets, useshields to stop rivets from flying andinjuring someone.
• When rivets are driven out with a punch,the helper should hold the punch with atongs or another suitable tool—not withtheir hands.
Q Decking and Floor Openings
The hoisting and installation of Q-Deck is acommon job for many ironworkers. Each taskcomes with its own set of risks. Here are someprecautions to help reduce the hazards.
• Never use bundle packaging or strappingto hoist the deck to upper floors.
• If loose items are placed on top of abundle for hoisting they must be securedto the bundle.
• Bundles must be landed on framingmembers so that the bundles aresufficiently supported to allow un-bandingwithout dislodging the bundles.
• Depending on weather conditions, such aswind, all decking must be secured so thatit doesn’t fly off and hit someone.
• Confirm with the steel erector that the steelis plumb and torqued before hoistingbundles to the upper levels.
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• All floor openings must be coveredimmediately. This includes small holes, ifany part of a worker can go through them.The covers must be secured and markedwith a warning sign or marking.
• Holes and openings must not be cut unlessthey are essential to the constructionprocess. If cut, they must be immediatelycovered.
• The spaces around columns must becovered or blocked to prevent objects fromfalling.
Due to the nature of Q-Decking installations,access to the floor where the decking is beingplaced and the area below it must be limited topersons performing the work. Remember,proper fall protection is required until the deckis complete and guardrails are installed.
Take special care when weather conditions arepoor. For example, during winter months, thedecking can become very slippery. Wear propersafety boots with slip-resistant soles.
Safe Access and FallProtectionThe main areas of concern are fall protectionwhile working at heights and access to elevatedwork areas. The fundamentals are covered inthe chapter on fall protection, and aresupplemented by the following information.
General requirements
Fall protection must be used wherever workersare exposed to the hazard of falling:
– more than 3 metres (10 feet)
– more than 1.2 metres if the work area isused as a path for a wheelbarrow orsimilar equipment
– into operating equipment
– into water or another liquid
– into a hazardous substance or object
– through an opening in a work surface.
Where it isn’t practical to install guardrails, youmust employ fall protection measures which caninclude:
1) Fall prevention, such as
• protective covers over floor and roofopenings
• warning barriers and bump lines
• travel restraint.
2) Fall arrest, such as
• fall restriction
• fall arrest
• safety nets.
Regardless of type, every fall protection systemin Ontario construction must meet therequirements of the Occupational Health andSafety Act and the Construction Regulation(Ontario Regulation 213/91).
An integral part of fall protection is planning forwork access before you begin erecting steel.Improper access leads to workers walking longdistances on the steel. The longer you walk onthe steel, the greater your risk of falling.
The employer must also develop writtenprocedures for rescuing a worker whose fall hasbeen arrested. Workers using fall protectionmust be trained in its use, and a written recordof training must be kept.
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Fig. 15: Q-Decking
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Travel-Restraint Systems
A travel-restraint system lets a worker go just farenough to reach the edge but not far enough tofall over it.
The basic travel-restraint system consists of
• CSA-approved full-body harness
• lanyard
• lifeline
• rope grab to attach harness or lanyard tolifeline
• adequate anchorage, capable of supportinga static load of 2 kilonewtons (450 pounds)with a recommended safety factor of at least2, that is, 4 kilonewtons or 900 pounds.
Travel-restraint arrangements must bethoroughly planned, with careful considerationgiven to
• selection of appropriate components
• location of adequate anchor points
• identification of every fall hazard in theproposed work area.
Try to select an anchor point that is as close aspossible to being
• perpendicular to the unprotected edge,and
• at the centre of the work area.
You must identify all fall hazards in the workarea. Pay special attention to work areas withirregularly shaped perimeters, floor openings, orlocations near corners. A fully extended lifelineand/or lanyard that keeps a worker away from afall hazard in one section of the work area maybe too long to provide the same protection inanother section.
Two methods of travel restraint are commonlyused in construction.
• Connecting an adequately anchored lifelinedirectly to the D-ring of the worker’s fullbody harness. It’s absolutely critical that
the length of the lifeline, measured fromthe anchor point, is short enough to keepthe worker away from any fall hazard.
• Attaching a lanyard to the D-ring of theworker’s full body harness and then to arope grab on an adequately anchoredlifeline. There must be some means—suchas a knot in the lifeline—to prevent therope grab from sliding along the lifeline toa point where the worker is no longerprevented from falling.
Regardless of the method used, the system mustbe adjusted so that when all the componentsare fully extended, they prevent the workerfrom reaching a fall hazard. The system mustalso be securely anchored.
FALL-ARREST SYSTEMSWhere workers cannot be protected from fallsby guardrails or travel restraint, they must beprotected by at least one of the followingmethods:
- fall-restricting system
- safety net
- fall-arrest system.
In the event of a fall, these systems must keep aworker from hitting the ground, the next levelbelow, or any other objects below.
A fall-restricting system is designed to limit aworker’s free fall distance to 0.6 metres (2 feet).One type uses a belt grab or belly hook thatattaches to a safety rail on a fixed ladder.
A safety net system must be designed by aprofessional engineer. The system is installedbelow a work surface where a fall hazard exists.
A fall-arrest system
• must include a CSA-approved full bodyharness
• must include a lanyard equipped with ashock absorber unless the shock absorbercould cause a falling worker to hit the
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ground or an object or a level below thework
• must include an adequate fixed support;the harness must be connected to it via alifeline, or via a lanyard and a lifeline
• must prevent a falling worker from hittingthe ground or any object or level belowthe work
• must not subject a falling worker to a peakfall-arrest force greater than 8 kilonewtons.
The construction regulation (O. Reg. 213/91)requires that
• all fall protection equipment must beinspected for damage, wear, and obviousdefects by a competent worker beforeeach use
• any worker required to use fall protectionmust be trained in its safe use and propermaintenance.
Any defective component should be replaced byone that meets or exceeds the manufacturer’sminimum performance standards for thatparticular system.
The regulation also requires that any fall-arrestsystem involved in a fall be removed fromservice until the manufacturer certifies allcomponents safe for reuse.
For any worker receiving instruction in fallprotection, the manufacturer’s instructions foreach piece of equipment should be carefullyreviewed, with particular attention to warningsand limitations.
ANCHOR SYSTEMSThere are three basic types of anchor systemsfor fall protection.
1) Designed fixed support: Load-ratedanchors specifically designed andpermanently installed for fall protection
purposes as an integral part of the buildingor structure (for example, roof anchors onhigh-rise buildings).
2) Temporary fixed support: Anchor systemsdesigned to be connected to the structureusing specific installation instructions (forexample, stanchions for horizontallifelines).
3) Structural features or equipment notintended as anchor points but verified by aprofessional engineer or competent personas having adequate capacity to serve asanchor points (for example, structural steelor reinforced concrete columns).
Designed fixed support can be used to anchor afall-arrest system, fall-restricting system, ortravel-restraint system if the support has beeninstalled according to the Building Code and issafe and practical to use.
Temporary fixed support can be used asanchorage if, without exceeding the allowableunit stress for each component used,
• it can support at least 8 kilonewtons (1800pounds), or
• when used with a fall-arrest systemincorporating a shock absorber, it cansupport at least 6 kilonewtons (1350pounds), or
• when used with a travel-restraint system, itcan support at least 2 kilonewtons (450pounds).
In all cases, use a safety factor of at least twowhen calculating the minimum load that ananchor point must support.
As a general rule with fall-arrest systems, choosean anchor capable of supporting the weight of asmall car (about 3600 pounds).
When structural features or equipment are usedas anchor points, avoid corners or edges thatcould cut, chafe, or abrade fall-protectioncomponents. Where necessary, use softeners
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such as wood blocking to protect connectingdevices, lifelines, or lanyards from damage.
Beam Clamps
Beam clamps can make effective anchors whenused properly with a correct lanyard. There aremany different types of beam clamps. The mostcommon are plate clamps, trolley clamps, orglider clamps. The pin set must be inserted thefull length of the pin, or if the clamp has alocking device, the device must be in the lockedposition. Always check that the clamp is set forthe correct beam size and that it is tight. Alwayscheck the manufacturer’s instructions beforeuse.
Before using a beam clamp, check forcoped ends on the beams. A beam clampcould easily slide off the end of a copedbeam through the gap between the twomembers.
Lifelines
There are three basic types of lifelines.
1) vertical
2)horizontal
3) retractable.
All lifelines must be inspected daily to ensurethat they are free of
• cuts, burns, frayed strands, abrasions, andother defects or signs of damage
• discolouration and brittleness indicatingheat or chemical exposure.
Vertical lifelines
Vertical lifelines must comply with the currentedition of the applicable CSA standard and thefollowing minimum requirements:
• Only one person at a time may use avertical lifeline.
• A vertical lifeline must reach the ground ora level above ground where the workercan safely exit.
• A vertical lifeline must have a positive stopto prevent the rope grab from running offthe end of the lifeline.
Vertical lifelines are typically 16-millimetre (5/8-inch) synthetic rope (polypropylene blends).
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Fig. 16. Danger: Beam clamp near coped end
Fig. 17.Vertical Lifeline
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CLIMBING THE COLUMNS FOR STEELCONNECTIONSThe first choice of a means of access for makingsteel connections must be a ladder, poweredelevating work platform, or a crane with aplatform suspended from the boom. You shouldonly climb columns when these options are notpractical due to
• characteristics of the location
• poor soil conditions.
Further to this, written notice must be given tothe Joint Health and Safety Committee or Healthand Safety Representative on the project beforea worker can climb the column. The workermust also be competent to climb and must beprotected by a fall arrest system at all times.
Horizontal Lifelines
The following requirements apply to anyhorizontal lifeline system.
• The system must be designed by aprofessional engineer according to goodengineering practice.
• The design can be a standard design orspecifically engineered for the site.
The design for a horizontal lifeline systemmust
• clearly indicate how the system is to bearranged, including how and where it is tobe anchored
• list and specify all required components
• clearly state the number of workers thatcan safely be attached to the lifeline at onetime
• provide instructions for installation,inspection, and maintenance
• specify all of the design loads for thesystem.
The system must be installed, inspected, andmaintained in accordance with the professionalengineer’s design.
Before each use, the system must be inspectedby a professional engineer or competent workerdesignated by a supervisor. A complete andcurrent copy of the design must be kept on siteas long as the system is in use.
CAUTION: The construction regulation requiresthat "a horizontal or vertical lifeline shall be keptfree from splices or knots, except knots used toconnect it to a fixed support." Knots along thelength of either a horizontal or vertical lifelinecan reduce its strength by as much as 40%.
Retractable Lifelines
Retractable lifelines must comply with thestandard CAN/CSA-Z259.2.2-M98. In general,retractable lifelines
• are usually designed to be anchored abovethe worker
• employ a locking mechanism that lets lineunwind off the drum under the slight
Fig.18. Horizontal Lifeline
Fig.19. Retractable lifeline
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tension caused by a user’s normalmovements
• automatically retract when tension isremoved, thereby preventing slack in theline
• lock up when a quick movement, such asthat caused by a fall, is applied
• are designed to minimize fall distance andthe forces exerted on a worker’s body byfall arrest.
Anchor your lifeline as close to overhead aspossible. This will minimize swing distance ifyou fall.
Always refer to the manufacturer’s instructionsregarding use, including whether a shockabsorber is recommended for the system.
A retractable lifeline that has stopped a fall mustbe removed from service until the manufactureror a qualified testing company has certified itfor reuse.
Lifeline Hazards
Ultraviolet (UV) light — Exposure to the sunmay damage or weaken lifelines. Ensure thatmaterial being considered for lifelines is UV-resistant.
Temperature — Extreme heat can damagelifelines, and extreme cold can make thembrittle. Ensure that the material being consideredfor lifelines can stand up to the most extremeconditions expected.
Friction and abrasion — Normal movementmay wear, abrade, or otherwise damage lifelinesin contact with sharp or rough surfaces. Useprotection such as wood softeners or rubbermats can at contact points to prevent wear andtear.
Sparks or flame — lifeline can be damagedwhen hot work such as welding or flame cuttingis done nearby. Sparks, flame, or heat can melt,burn, cut, or otherwise damage the lifeline.Ensure that material being considered for
lifelines is flame-resistant or provide appropriateprotection when hot work is done nearby.
Chemicals — Chemical exposure can burn ordegrade a lifeline very quickly. Ensure thatmaterial being considered for lifelines will resistany chemicals encountered on the job.
Storage — Always store lifelines separately.Never store them where they may contacthazards such as sharp objects, chemicals, orgasoline.
Ladders
Ironworkers use ladders extensively to accesselevated work areas, and in some cases they’reused for short-duration work. Portable extensionladders are the most common in the ironworkertrade, but they have been responsible fornumerous injuries. Falls, electrical contact andmaterial handling are the main injuriesassociated with ladders. If ladders are beingused as work platforms, check the ConstructionRegulation for whether fall protectionrequirements apply in your case. For example,you may require a method of fall protectionsuch as the vertical lifeline shown in Figure 17.
See the chapter on Ladders in this manual formore information.
Construction Hoists
Construction hoists are used on constructionsites to move workers and light materials toupper floors. Normally they are operated by adesignated operator, but all workers shouldfollow some basic safety precautions.
The landing gates on hoists are for yourprotection. Make sure that the gates are closedproperly before the car leaves the floor. Don’ttry to bypass gate contacts.
Removable guardrails at landings are animportant safety feature. If they must beremoved at any time during construction,replace them before you leave the area. Whenyou’re working in an area where guardrails havebeen removed, you must have another methodof fall protection.
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38 – 26
Landing areas must be kept clear of materials,tools, and debris to ensure safe access to thehoist entrance.
Do not tamper with shoring under ramps orother parts of the hoist. In particular, shoringunder the hoist must be kept intact until thetower is removed.
Don’t remove a brace or anchor connecting thetower to the structure unless it’s absolutelynecessary. It must be replaced immediately. Thehoist must be taken out of service whenever abrace is removed.
Angel Wing Scaffolds
Angel wing scaffolds are a lightweightconstruction platforms used for applicationssuch as steel erection, bridgework, shipbuilding,welding and cutting, and tank inspection andrepair. They are normally made from a lightaluminum alloy that is easily installed,dismantled, and carried by one person. Angelwings have a compact, folding design. Eachcomponent must be designed so that the stagecan hold the minimum load for a work platformas specified in the Construction Regulation.They normally accommodate one or twoworkers—but all workers on the platform mustwear fall protection.
Mobile Welding RigsThis section describes some basic requirementsfor drivers of mobile welding rigs. If you haveany questions or concerns, speak with theappropriate association or ministry to ensurethat you understand the responsibilities of allpersonnel.
Legislation
Highway Traffic Act
On public roads and highways all vehicles mustoperate in compliance with the Highway TrafficAct. The Transportation Health and SafetyAssociation of Ontario (THSAO) providesinformation and training on the Act.
Commercial Plates
You need commercial plates on any motorvehicle having a permanently attached truck ordelivery body. The requirement for commercialplates on a van or pickup, however, does notautomatically classify them as commercialvehicles.
Commercial Vehicles
Loading a vehicle with equipment and suppliescan increase its weight. Whenever the grossvehicle weight rating, registered gross weight, oractual weight, loaded or empty, exceeds 4500kilograms, the vehicle and operator are subjectto the regulations under the Highway Traffic Actapplying to commercial motor vehicles andcommercial motor vehicle operators. You mustadd a trailer’s weight to the weight of thevehicle when determining total weight.
Under the Highway Traffic Act, commercialvehicle operators must obtain a CommercialVehicle Operator’s Registration (CVOR). Theymust also comply with the additional restrictionsand obligations (such as annual inspections)described in the Act.
According to the Highway Traffic Act, theoperator is the "person responsible for theoperation of a commercial motor vehicleincluding the conduct of the driver and thecarriage of goods or passengers, if any, in thevehicle or combination of vehicles." Theoperator does not have to be the vehicle owner.If the vehicles are leased or contracted, theoperator must hold a valid CVOR.
If you have any questions about how theHighway Traffic Act is applied, contact thelocal Ministry of Transportation enforcementoffice. For a CVOR application form, contactthe Carrier Sanctions and Investigation Office.
Gross Axle Weight
For any commercial or passenger vehicle, thegross weight of the vehicle or combination ofvehicles (e.g., van and trailer) must not exceedthe manufacturer’s gross axle weight rating. This
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IRONWORKERS: STRUCTURAL STEEL
rating is usually written on a sticker on thedriver’s door.
There are two consequences of exceeding themanufacturer’s gross axle weight rating. First, itis an offence under the Highway Traffic Act.Second, if the gross weight is more than 4500kilograms, the vehicle can be classified as acommercial vehicle.
Trailers
If a vehicle is towing a trailer such as a utilitytrailer, the trailer’s weight must be added to theweight of the vehicle when determining totalweight. Add the highest weight of the vehicle tothe highest of the trailer’s gross vehicle weightrating (if provided on trailer) or the actualweight, empty or loaded, to determine whetherthe combined weight exceeds 4500 kilograms.
Transportation of Dangerous Goods Act(TDG Act)
The Transportation of Dangerous Goods Act(TDG Act) applies whenever hazardous materialis transported on a road or highway. Learnabout the dangers involved. Learn also aboutthe restrictions and obligations that the TDG Actapplies to the driver and owner of the vehicle.
This section only identifies some of theregulations and exemptions which apply tomobile welding rigs, vehicle owners, and driversunder the TDG Act. For more information,contact the Transportation Health and SafetyAssociation of Ontario (THSAO)—whichprovides training—or the local Ministry ofTransportation Enforcement office.
When transporting propane, drivers must alsofollow the Propane Storage and Handling Code.
Read the material safety data sheet (MSDS) ofeach product you’re transporting. It maydescribe specific information about transportingthe product.
Special Provisions of the TDG Regulations
under the TDG Act
Regulations under the TDG Act always applywhen you’re transporting dangerous goods such
as compressed gases. There are, however, someexemptions.
You may, for example, be exempt from drivertraining, documentation, and placarding of thevehicle. (Placarding means putting signs on thevehicle to identify the material beingtransported.) There may also be exemptionswhen propane, acetylene, or oxygen is beingtransported in an open vehicle, and the amountis less than 500 kilograms gross mass or iscontained in not more than five cylinders. Inthis situation, the TDG Act does require thelabel on the cylinder to be visible from outsidethe vehicle. Also see the Propane Storage andHandling Code. In all cases the cylinders mustbe securely stowed in the vehicle to preventmovement. You should have in the vehicle adry-chemical fire extinguisher of at least 10BCrating — one that’s listed by the Underwriters’Laboratories of Canada.
Depending on the hazardous material, the TDGAct could require the driver and others toreceive training in the transportation ofdangerous goods.
GENERAL PRECAUTIONS
Defensive Driving
Defensive driving means being prepared. Donot simply focus on getting to your destination.Think also about actions and events that caninfluence the way your trip unfolds. Beprepared to avoid or control hazards. Followcommon-sense rules for defensive driving.
1. Understand the rules and regulations thatapply to the vehicle and to driving.Ignorance of the law is not a valid defencein court.
2. Understand that human physical andemotional factors influence drivingperformance.
3. Ensure that the vehicle is well maintainedand operating properly.
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4. Consider how weather, road, and trafficconditions will affect driving abilities.
5. Assess how well you understand theprevious four topics. Take steps such asenrolling in a defensive driving course toattain and maintain a level of knowledgenecessary to practice defensive driving.
Trailer Safety
Before using a trailer, be sure it is in safeoperating condition. Inspect
• lights
• tires
• brakes
• bearings
• safety chains
• hitch.
Use the correct class of trailer hitch on yourvehicle.
• Class I – up to 2,000 lb
• Class II – up to 3,500 lb
• Class III – up to 5,000 lb
• Class IV – up to 10,000 lb
A trailer requires two separate means ofattachment to the vehicle. A typical arrangementincorporates a ball hitch with two safety chains.The capacity of each chain should be equal tothe gross weight of the trailer and should crossunder the tongue to connect to the hitch.
Loose objects must be covered with a tarp. Allloads on trucks and trailers must be secured orplaced so that no portion of the load canbecome dislodged of fall from the vehicle.
Anchor points, rope, and slings used for tie-downs must be in good condition. Inspect thembefore each use. See CSAO’s Hoisting andRigging Safety Manual (M035) for moreinformation.
Maintenance
Every employer should establish a system forperiodical inspection, repair, and maintenanceof all motor vehicles and trailers operated onthe highway.
An employer must not permit a motor vehicle tobe driven, or a trailer to be towed, on ahighway if there is reason to believe that thevehicle or trailer will not meet safety standards.
A driver who reasonably believes or suspectsthat a vehicle or trailer does not meet safetystandards should advise the employer.
Inspections
Before each shift, perform a basic vehicleinspection. The following “Daily Circle Check” isa good example:
Parking brake – adequate to hold vehicle.
Fluid levels – oil, gas, brakes. Check for leaks.
Lights and turn signals – functioning.
Visibility check – mirrors properly adjusted,windows clean and intact.
Wiper/washer – functioning.
Tires – pressure, tread depth, damage.
Wheels and fasteners – defects in rim, looseor missing fasteners.
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Fig. 20. Daily Circle Check
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Seat belts – you must always wear them.
Load – secure.
Emergency equipment – install and inspectas required by law or company policy.
A more detailed inspection may be requiredfor commercial vehicles.
Record and report any defects to yoursupervisor immediately!
Users should consult the Transportation ofDangerous Goods Act, applicable highway trafficacts, provincial regulations, local bylaws, etc.,which may contain additional safetyrequirements.
Vehicle Layout
CSA standard CAN/CSA-W117.2 providesguidance for mobile welding rig design.
When a mobile oxygen/fuel gas welding systemis assembled as a cutting/welding or heatingunit, a person capable of competently operatingthe equipment should accompany the vehicle.This person must ensure that the system isbeing transported in compliance with theTransportation of Dangerous Goods Act andwhere applicable, the Highway Traffic Act.
When designing and laying out a welding rig,do the following.
• Secure any cargo that could shift duringtravel. Set up strong storage racks for tools
and supplies to distribute the weightevenly and prevent shifting during suddenstops or sharp turns.
• Do not let scrap and debris accumulateinside the vehicle.
• Set up a designated location for the firstaid station, MSDS information, and fireextinguisher.
• Install a strong reinforced divider toseparate the driver compartment from theback.
Compressed gases
• Ensure that cylinders are supported solidlyand fit snugly into their designatedlocations. Restrain cylinders in a way thatprevent them from rotating. Provide acylinder-mounting location that is easilyaccessible, minimizes lifting, and permitsthe cylinders to be installed or removedwithout dragging or scraping them.
• Ensure that all cylinders are standingupright.
• Do not store fuel gas cylinders in cabinets.Ventilation holes in a cabinet may not beadequate to vent leaking fuel gas. Forexample, acetylene has an explosive rangestarting at 2.5%, so an explosiveatmosphere can develop quickly.
Warning
Gas can leak from stored fuel hoses andgauges, causing an explosive atmosphere.
• If you’re concerned about theft orvandalism, you can build a screened cageto contain the cylinders. At least two sidesof the cage must have an 80% or greaterfree area.
• Mount all cylinders vertically unless themanufacturer’s MSDS says otherwise.
• Before you operate your vehicle on publicroadways, or park it on publicly accessible
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Fig. 21
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property, disconnect the regulators andhoses from the cylinders and put themaway in storage. The valves must beclosed on all cylinders and the protectioncaps must be in place.
• Close the cylinder valves when theequipment is unattended.
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