Unit 3

105
Safety for Aluminum Processing and Finishing Operations Involving Combustible Dust in the Die Casting Industry Unit 3 DCA h American Die Casting Association

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NADCA North American Die Casting Association. Safety for Aluminum Processing and Finishing Operations Involving Combustible Dust in the Die Casting Industry. Unit 3. Enabling Objectives. After completing this section of the course students should be able to: - PowerPoint PPT Presentation

Transcript of Unit 3

Page 1: Unit 3

Safety for Aluminum Processing and Finishing Operations Involving

Combustible Dustin the

Die Casting IndustryUnit 3

NADCA North American Die Casting Association

Page 2: Unit 3

Enabling Objectives

Explain procedures for housekeeping, dust collection, fire prevention, prevention of accumulation of fugitive dusts, proper storage, and safety procedures for aluminum and magnesium.

After completing this section of the course students should be able to:

Discuss aluminum dust producing operations and the precaution for carrying out these operations safely

Page 3: Unit 3

• Two recognized methods to capture aluminum dust:– Wet collectors located near the point of

generation

– Dry collectors located outdoors as near as possible to the point of generation

– Machines fitted with hoods and capture devices able to capture and transport all the dust that is produced

Dust Producing Operations

Page 4: Unit 3

• Design system so all dust

moves into the hoods, into the

ducts and is collected

• Connecting ducts must be

kept as straight and short as

possible

Dust Producing Operations

Page 5: Unit 3

Ductwork

• Duct runs as short & straight as possible!

Page 6: Unit 3

• Metal dust-air

suspension can pass

into the explosive

range in the collector!

Dust Producing Operations

Page 7: Unit 3

• Dry-type provided with

barriers or other protection

• Area around collector

posted with Caution Sign

• Personnel outside of

marked area when

operating

CAUTION: This dust collector can

contain explosible dust.

Keep outside the marked area while

equipment is operating.

CAUTION

CAUTION:

This dust collec

tor can c

Page 8: Unit 3

• Dedicated equipment not to be

used with other types of metals

• Grinders, buffers posted with

warning sign!

Warning: Aluminum Metal Only – Fire or Explosion Can

Result with Other Metals.

!

Warning: Aluminum Metal Only – Fire or Explosion Can

Result with Other Metals.

Hi Aluminum!I’m another type

of metal!Kaboom!

Page 9: Unit 3

• Practice Quiz• 1. Duct runs for dust collectors should be:

– A. As far away from the machine feeding into it as possible.– B. Build with curves and turns to slow down the movement of

dust.– C. As short and straight as possible.

• 2. When dry-type dust collectors are operating:– A. They should be indoors near the point of generation.– B. Barriers should be established and personnel should stay

away.– C. Maintenance personnel should open them up to ensure

they are working properly.

Dust Producing Operations

Page 10: Unit 3

• Practice Quiz• 3. Grinders and buffers used for aluminum must be:

– A. Dedicated equipment.– B. Used for all types of metal including stainless steel– C. Disconnected from dust collection units when used for

other metals.

Dust Producing Operations

Page 11: Unit 3

• Practice Quiz• 1. Duct runs for dust collectors should be:

– A. As far away from the machine feeding into it as possible.– B. Build with curves and turns to slow down the movement of

dust.– C. As short and straight as possible.

• 2. When dry-type dust collectors are operating:– A. They should be indoors near the point of generation.– B. Barriers should be established and personnel should

stay away.– C. Maintenance personnel should open them up to ensure

they are working properly.

Dust Producing Operations

Page 12: Unit 3

• Practice Quiz• 3. Grinders and buffers used for aluminum must be:

– A. Dedicated equipment.– B. Used for all types of metal including stainless steel.– C. Disconnected from dust collection units when used for

other metals.

Dust Producing Operations

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• Permitted to be used indoors when moving work piece is infeasible

• Perform hazard analysis to minimize risk from fire & shrapnel

• Limit collector capacity to < 1 lb

• Empty daily

Individual Machines with Portable Dust Collection

Filtering Media

Portable Media-Type Dust Collector

Material Discharge

Page 14: Unit 3

• Cyclone’s are less

hazardous than bag-

or media-type

• Exhaust discharge to

atmosphere away

from other operations!

Portable Dust Collectors

Page 15: Unit 3

Fixed MediaType DustCollector

NOT the best choice!

MaterialDischarge

Filtration Media

Build a barrier

around the equipment!

Dust Producing Operations• Dry collectors

required to be located outdoors

• (exception: small portable units

• Dry collectors provided with barriers

Page 16: Unit 3

Dust Collection, Ducts and Ductwork

• Collector area is to be marked and a sign posted

• NFPA 68: length of a fireball from a vented collector

• Collection system dedicated to aluminum only!

This dust collector can contain explosive dust,

keep outside the marked area while equipment is

running

20'

Page 17: Unit 3

• Experts indicate an eventual explosion can be expected from bag collectors use for aluminum fines!

• Multiple-series cyclone with final liquid stage is a better choice

Not so good…

Can lead to I’m a better choice

Page 18: Unit 3

Dust Collection, Ducts and Ductwork

If the collection system used for combustible aluminum dust is used for other materials it should be disassembled and cleaned before and after.

Page 19: Unit 3

Dust Collection, Ducts and Ductwork

• Use separate collection

systems for grinding and buffing

operations

• The dust collector should

dissipate static electricity

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• For bag-house shake-out

design to minimize sparking

• Pulse-types less likely to

create a spark because there

are no moving parts

• Attach ground wires to bags

and securely ground

Dust Collection, Ducts and Ductwork

Mechanical Shaker Baghouse

Page 21: Unit 3

• For baghouse an alarm sounds for

pressure drop across bags

• Locate baghouse or media type

collector > 50 feet from other

operations and buildings!

• Keep personal > 50 feet away

when shaking!

Dust Collection, Ducts and Ductwork

At least I’m outside!

Page 22: Unit 3

• Avoid letting aluminum

impact oxidized iron!

• Thermite reaction possible for

impact with aluminum &

rusted iron or steel

• Enough heat to produce

molten iron!

Thermite Reaction

Laboratory createdthermite reaction

Page 23: Unit 3

• Practice Quiz• 1. Baghouse collectors for aluminum:

– A. Are both economical and efficient.– B. Are considered better than cyclone collectors.– C. Have been associated with fires when used for aluminum.

• 2. If aluminum impacts iron oxide:– The material produced is inert.– A dangerous thermite reaction can be initiated.– It makes a valuable by-product that is a commodity.

Dust Collection, Ducts and Ductwork

Page 24: Unit 3

• Practice Quiz• 3. If a baghouse type collector is used:

– A. A pulse-type is better than a mechanical shaker.– B. The collector should be located outdoors at least 50 feet away from

buildings and other equipment.– C. Barriers and warning signs should be posted around the equipment.– D. All of the above

• 4. Dust collection for grinding and buffing operations should be:– A. A single unit with adequate capacity for the amount of dust generated.– B. Located between the grinder and buffer.– Served by separate dust collection systems.

Dust Collection, Ducts and Ductwork

Page 25: Unit 3

• Practice Quiz• 1. Baghouse collectors for aluminum:

– A. Are both economical and efficient.– B. Are considered better than cyclone collectors.– C. Have been associated with fires when used for

aluminum.• 2. If aluminum impacts iron oxide:

– The material produced is inert.– A dangerous thermite reaction can be initiated.– It makes a valuable by-product that is a commodity.

Dust Collection, Ducts and Ductwork

Page 26: Unit 3

• Practice Quiz• 3. If a baghouse type collector is used:

– A. A pulse-type is better than a mechanical shaker.– B. The collector should be located outdoors at least 50 feet away from

buildings and other equipment.– C. Barriers and warning signs should be posted around the equipment.– D. All of the above

• 4. Dust collection for grinding and buffing operations should be:– A. A single unit with adequate capacity for the amount of dust generated.– B. Located between the grinder and buffer.– Served by separate dust collection systems.

Dust Collection, Ducts and Ductwork

Page 27: Unit 3

• Explosion vents are usually

built into the system

• If not a retrofit is a good idea!

• Locate Explosion Vents away from personnel!

Explosion vents for dust collectors

Explosion Ventinglocated away from personnel

It’s a good thing!

Page 28: Unit 3

Ductwork • Ducts short and straight to

maximize free airflow

• No dead ends or unused

caps in ducts that could

trap accumulations of dust

• Ducts grounded & bonded

to dissipate static

electricity

Page 29: Unit 3

Particles are suspended

Air velocity at least 4500 ft/min

Build-up of dust particles

Air velocity less than 3500 ft/min

Entrainment! is what you need!

Bad!

Page 30: Unit 3

Duct Construction• Ducts made of

conductive material

• Lap joints face airflow direction

• No unused or capped outlets

• Duct seams away from personnel!

Smellslikesomething’sburning!

Page 31: Unit 3

Duct Construction• No add-ons without

engineering redesign of

system and the impact the

add-ons will have

• Collectors and machines that

generate combustible dust

properly bonded & groundedCopper wire is securely fastened to the equipment and then grounded to earth, for example by attaching it to a metallic water pipe or other object connected with earth.

Preventsbuildupof staticcharges!

Page 32: Unit 3

Dust Collection & Ductwork• Practice Quiz• 1. Explosion vents:

– A. Should be built into collectors for combustible aluminum dust.

– B. Located away from personnel.– C. Not necessary under normal circumstances.– D. Both A & B.

• 2. Ducts for dust collectors should have:– A. Dead end sections to help collect dust at the point of

generation.– B. Unused caps to maintain duct velocity pressure.– C. No dead ends or unused caps.

Page 33: Unit 3

Dust Collection & Ductwork• Practice Quiz• 3. Dust collectors and machines:

– A. Isolated from ground to prevent conducting electricity.

– B. Properly grounded and bonded.– C. Designed and installed to dissipate static

electricity.– D. Both B & C.

Page 34: Unit 3

Dust Collection & Ductwork• Practice Quiz• 1. Explosion vents:

– A. Should be built into collectors for combustible aluminum dust.

– B. Located away from personnel.– C. Not necessary under normal circumstances.– D. Both A & B.

• 2. Ducts for dust collectors should have:– A. Dead end sections to help collect dust at the point of

generation.– B. Unused caps to maintain duct velocity pressure.– C. No dead ends or unused caps.

Page 35: Unit 3

Dust Collection & Ductwork• Practice Quiz• 3. Dust collectors and machines:

– A. Isolated from ground to prevent conducting electricity.

– B. Properly grounded and bonded.– C. Designed and installed to dissipate static

electricity.– D. Both B & C.

Page 36: Unit 3

Wet-Type Dust Collector• Exhaust to the outside of building

• Exhaust duct as short & straight

as possible

• Ducts designed to withstand

same explosion pressure as wet-

type collector

Page 37: Unit 3

Wet-Type Dust Collector

• Aluminum and water can

produce hydrogen gas

• Extremely flammable and easy

to ignite

• Don’t trap in unventilated areas of the building or equipment!

Page 38: Unit 3

Wet-Type Dust Collector• Return air tested and approved for recirculation• Exhaust vent inspected and cleaned frequently• Particles can collect on the walls of the exhaust

duct and can be highly combustible

Particles Collecting onexhaust duct

I’m forming a highly combustible cake!

Page 39: Unit 3

Water level

sludge

Liquid level control w/ interlock

Non-sparking work surface

Liquid Precipitator Collector For Portable Dust Collector

Mist eliminator packs

Expanded metal aluminum mesh

Wet-Type Dust Collector

Page 40: Unit 3

Sludge & Collector Sump Venting

• Wetted dust is

highly flammable!

• Sludge removed

regularly

• Collector sump

vented!

H2H2

H2

H2

H2 H2

H2

H2

H2

H2

H2

H2

H2

H2

H2 H2

H2H2

H2

Page 41: Unit 3

Power Supply• Interlocked with the

exhaust blower and the

liquid-level controller

• Time delay on dust

producing equipment

prevents motor starting

until collector is operating

To dust producingequipment

Power to dust-producing eq. motor

cutoff by low liquid levelor

low airflow

Inspection/Cleanout door

Water level

Overflow/Drain Piping

Liquid levelcontrol w/interlock

Sludge in tank

Mist EliminatorPacks

My power supply is dependent onmy proper functioning

Page 42: Unit 3

Sludge Removal• Sludge removed daily

• Covered vented containers for transport

• Containers filled to < 50 lbs

Page 43: Unit 3

Sludge Removal• NO SMOKING

ALLOWED!

• Mix with inert at 5:1

ratio & dispose of

properly

• Hot Work requires a Permit use one!

Page 44: Unit 3

Wet-Type Collectors• Practice Quiz• 1. Wet aluminum dust:

– A. Is inert– B. Is easily removed with steel shovels– C. Can generate explosive hydrogen gas

• 2. Exhaust air:– A. Should be vented to the outside– B. Should be tested if it is to be returned to the building.– B. Both A & B.

Page 45: Unit 3

Wet-Type Collectors

• Practice Quiz• 3. Sludge from wet-type dust collectors for

combustible aluminum dust should be:– A. Emptied daily.– B. In containers of less than 50 lbs.– C. Covered in vented containers for disposal

transport.– D. All of the above.

Page 46: Unit 3

Wet-Type Collectors• Practice Quiz• 1. Wet aluminum dust:

– A. Is inert– B. Is easily removed with steel shovels– C. Can generate explosive hydrogen gas

• 2. Exhaust air:– A. Should be vented to the outside– B. Should be tested if it is to be returned to the building.– B. Both A & B

Page 47: Unit 3

Wet-Type Collectors

• Practice Quiz• 3. Sludge from wet-type dust collectors for

combustible aluminum dust should be:– A. Emptied daily.– B. In containers of less than 50 lbs.– C. Covered in vented containers for disposal

transport.– D. All of the above.

Page 48: Unit 3

Dry-Type Dust Collectors• Use only where permitted

• Collection containers covered to prevent

airborne fugitive dust

• Collector designed and maintained to ensure internal cleanliness!

• No accumulation of material allowed

except discharge container

Page 49: Unit 3

Dry-Type Dust Collectors• Dust-collecting filter medium conductive

with enmeshed noninsulated wire

woven or fastened to it

• Not fool proof:• No force passes charge across nonconductive

areas of the fabric

• Broken wires can hold or build-up a charge!

Page 50: Unit 3

Dry-Type Dust Collectors• Hoods regularly cleaned

• Dry collectors for aluminum

dust provided with

deflagration vents

• Air from dry dust collectors is not to be recycled back into the building

Courtesy ofFenwal SafetySystems

Page 51: Unit 3

Dry-Type Dust Collectors• Selection of type and location of

weak sections or vents designed to minimize injury to personnel and minimize damage to nearby equipment & structures

• Explosion venting is a very important consideration!

• Al: high explosion pressure

Courtesy ofFenwal SafetySystems

Page 52: Unit 3

Dry Type Dust Collectors• Practice Quiz• 1. Air from dry-type dust collectors:

– A. Should be vented back into the plant to balance negative pressure.

– B. Should be used to provide warmth around grinding operations.

– Should not be recycled back into the building.• 2. Grounding cartridge filters with wires built into the

cartridge :– A. Is a fool proof way of ensuring static charges will be

controlled.– B. Does not ensure that static charges will move across the

filter.– C. Never done.

Page 53: Unit 3

Dry Type Dust Collectors• Practice Quiz• 3. Dry type dust collectors should:

– A. Have their hoods regularly cleaned.– B. Be fitted with deflagration vents.– C. Allow for no accumulation of dust except

for in discharge containers.– D. All of the above.

Page 54: Unit 3

Dry Type Dust Collectors• Practice Quiz• 1. Air from dry-type dust collectors:

– A. Should be vented back into the plant to balance negative pressure.

– B. Should be used to provide warmth around grinding operations.

– Should not be recycled back into the building.• 2. Grounding cartridge filters with wires built into the

cartridge :– A. Is a fool proof way of ensuring static charges will be

controlled.– B. Does not ensure that static charges will move across

the filter.– C. Never done.

Page 55: Unit 3

Dry Type Dust Collectors• Practice Quiz• 3. Dry type dust collectors should:

– A. Have their hoods regularly cleaned.– B. Be fitted with deflagration vents.– C. Allow for no accumulation of dust except

for in discharge containers.– D. All of the above.

Page 56: Unit 3

Additional Considerations• Cutting tools sharp & sufficient coolant

flow to prevent ignition of turnings

• Cutting & grinding eq. grounded

• Chips, swarf, turnings, etc. collected in closed-top containers

• Removed daily to safe storage or disposal

Page 57: Unit 3

Additional Considerations

• Coolant non-flammable & filtered

• Collected solids max accumulation 5

gallons

Page 58: Unit 3

Additional Considerations• All electrical wiring conforms to NEC

• Collection systems bonded &

grounded

• Metallic jumpers installed when

continuous contact is interrupted

NEC

NFPA 70

Page 59: Unit 3

Housekeeping• No accumulation of fugitive

combustible dust

• Ignition of a dust cloud or layer will likely result in an explosion

• Often followed by a more violent explosion

• Good housekeeping is extremely important!

Page 60: Unit 3

Housekeeping• Regular cleanup using

conductive non-sparking tools

• Soft brooms with natural bristles

• Bulk of cleanup done with scoops, shovels & brooms

• Vacuum only small residual amounts

Non-sparking

Page 61: Unit 3

Housekeeping• Compressed air blow down is

generally not to be permitted

• Only allowed in areas otherwise impossible to clean

• Only allowed under carefully controlled conditions

• All potential ignition sources eliminated

• All equipment shut down

Page 62: Unit 3

Vacuum Cleaners• Vacuums only for too small,

dispersed or inaccessible dust• Bonded & grounded• Listed or approved for use

with combustible dust• Periodic continuity tests

performed• Dusts from fixed vacuums

collected to outside of building

Page 63: Unit 3

Fixed Vacuum Systems• If possible locate

vacuum collection outside facility

• 50 feet from building• If closer enclose in

open-top steel shield• Fit suction lines with

explosion vents and anti-flash back valves

50 ft

.

Page 64: Unit 3

Water Cleanup Considerations• Wet aluminum fines can evolve

hydrogen gas!• Keep hydrogen at or below 1%

concentration in air using ventilation (H2

LEL = 4%)

• Inform management of risks

• Competent person has determined wet cleaning is safest method available

Applies to AluminumDross: Wet or Hot

Page 65: Unit 3

Cleaning Frequency• Avoid excessive accumulation of dust on any

portion of building that is not cleaned during

regular daily operations

• Regular cleaning of buildings and machinery as

needed

• Machines idle and

power off

Page 66: Unit 3

Housekeeping• Practice Quiz• 1. Cleanup of aluminum dust should be done with:

– A. Non-combustible conductive tools.– B. Brooms with soft natural bristles.– C. Mostly scoops, shovels and brooms.– D. All of the above.

• 2. Compressed air blown for aluminum dust:– A. Is a fast and safe way to clean up.– B. Is a common practice.– C. Should only be done under controlled procedures when no other

method is feasible.

Page 67: Unit 3

Housekeeping• Practice Quiz• 1. Cleanup of aluminum dust should be done with:

– A. Non-combustible conductive tools.– B. Brooms with soft natural bristles.– C. Mostly scoops, shovels and brooms.– D. All of the above.

• 2. Compressed air blown for aluminum dust:– A. Is a fast and safe way to clean up.– B. Is a common practice.– C. Should only be done under controlled procedures when no

other method is feasible.

Page 68: Unit 3

Housekeeping• Practice Quiz• 3. Cleaning dust from the facility should:

– A. Include additional cleaning on all parts of the building where dust can accumulate that is not cleaned during normal operations.

– B. Be done as often as necessary.– C. Be done with machines idle with the power off.– D. All of the above.

Page 69: Unit 3

Fire Prevention & Protection• Large scale fires in

aluminum dust are very difficult to extinguish

• DO NOT create a dust cloud in an attempt to fight an aluminum dust fire!

• Attempt to control as quickly as possible with minimum disruption to the pile

Page 70: Unit 3

Fire Extinguishers• Ample Class ‘D’ fire

extinguishers should be available to fight incipient stage fires

• Available within 75 feet of metalworking areas.

• Required where dust is generated at least once every two weeks

Page 71: Unit 3

Fire Extinguishers

• Install signs so other

types of extinguishers are

not used by mistake!

Page 72: Unit 3

Extinguishing Agent• Ring incipient fires with dry

sand, or a Class D powder

• Properly ringed will form a

metal oxide crust

• Apply with non sparking

utensils

• Eliminate drafts, etc.

Page 73: Unit 3

Extinguishing Agent• Dry sodium chloride is very effective

• Check for caking

• Flux made of potassium and magnesium

chloride and calcium fluoride

• Avoid Class B agents for dry powder aluminum

fires, they will accelerate

fires or cause an explosion!

Page 74: Unit 3

Aluminum Slurry Fires• Incipient stage fires

involving a slurry

(wetted) of aluminum

powder can be fought

using a Class B type

extinguisher as long

as the agent is not

halogenated.

Page 75: Unit 3

Sprinkler Systems• No automatic sprinklers

where dry aluminum

powder is produced or

handled

• Consider the hazards

associated with aluminum

and water in considering

sprinkler systems

Page 76: Unit 3

Fire Prevention and Protection• Practice Quiz

• 1. Large aluminum fires:– A. Can be easily controlled with class ‘D’ fire extinguishers.

– B. Are extremely difficult to extinguish.

– C. Are best handled with class ‘B’ fire extinguishers.

• 2. Incipient stage aluminum fires:– A. Should be ringed with a Class ‘D’ extinguishing agent.

– B. Should have extinguishing material applied with non-sparking scoops.

– C. Should be protected from drafts.

– D. All of the above.

Page 77: Unit 3

Fire Prevention and Protection

• Practice Quiz• 3. Class ‘D’ fire extinguishers

– A. Are optional for aluminum dust processing areas.

– B. Only needed by the dust collector.– C. Are required where combustible dust is

produced at least once every two weeks.

Page 78: Unit 3

Fire Prevention and Protection• Practice Quiz

• 1. Large aluminum fires:– A. Can be easily controlled with class ‘D’ fire extinguishers.

– B. Are extremely difficult to extinguish.

– C. Are best handled with class ‘B’ fire extinguishers.

• 2. Incipient stage aluminum fires:– A. Should be ringed with a Class ‘D’ extinguishing agent.

– B. Should have extinguishing material applied with non-sparking scoops.

– C. Should be protected from drafts.

– D. All of the above.

Page 79: Unit 3

Fire Prevention and Protection

• Practice Quiz• 3. Class ‘D’ fire extinguishers

– A. Are optional for aluminum dust processing areas.

– B. Only needed by the dust collector.– C. Are required where combustible dust is

produced at least once every two weeks.

Page 80: Unit 3

Employee Training & Emergency Evacuation

• Train employees in

evacuation procedures

• Only trained employees are allowed to attempt to fight fires

• All others must evacuate!

Page 81: Unit 3

Fire Safety Training

• Familiarize fire departments

with the special potential

hazards present

• Plant safety officer to

provide instruction or direct

the efforts of fire personnel

Scrap metal fire“Will burn until it runs out of fuel”

Page 82: Unit 3

Fire Safety Training• Job hazard analysis

should be conducted and

safe work practices

developed

• Employees trained on

hazard recognition,

elimination and control

Don’t let this happen to you!

Page 83: Unit 3

Fire Prevention & Control• Set up test fires for fire

department training

• Cover foreseeable scenarios

and plan and prepare

accordingly

• Train employees for the

different types of fires

possible

Page 84: Unit 3

Fire Prevention & Control• Train employees on the

hazards present

• Focus on proper actions, decisions & procedures

• Train on location of controls, emergency supplies and fire extinguishers

The stuff you NEED!

Page 85: Unit 3

Fire Prevention & Control• Train on proper method

for fighting incipient stage aluminum dust fires

• Warn employees regarding the creation of a dust cloud or using liquids on combustible metal fires

Page 86: Unit 3

Fire Prevention & Control• Practice Quiz• 1. If you have not been trained you should:

– A. Only fight a major fire with coworkers who have experience.

– B. Only attempt to extinguish incipient fires.– C. Not attempt to put out combustible dust fires.

• 2. Your training should focus on hazard:– A. Recognition.– B. Elimination.– C. Control.– D. All of the above.

Page 87: Unit 3

Fire Prevention & Control• Practice Quiz• 1. If you have not been trained you should:

– A. Only fight a major fire with coworkers who have experience.

– B. Only attempt to extinguish incipient fires.– C. Not attempt to put out combustible dust fires.

• 2. Your training should focus on hazard:– A. Recognition.– B. Elimination.– C. Control.– D. All of the above.

Page 88: Unit 3

Fire Prevention & Control• Practice Quiz• 3. It is important not to:

– A. Put liquids on aluminum dust fires.– B. Use a high pressure extinguisher that will create

a dust cloud.– C. Use the wrong type of fire extinguisher.– D. All of the above.– E. None of the above.

Page 89: Unit 3

Fire Prevention & Control• Practice Quiz• 3. It is important not to:

– A. Put liquids on aluminum dust fires.– B. Use a high pressure extinguisher that will create

a dust cloud.– C. Use the wrong type of fire extinguisher.– D. All of the above.– E. None of the above.

Page 90: Unit 3

Controlling Ignition Sources• No smoking, cutting or

welding in areas where wet

sludge is present

• Any area where hot work

takes place must be free of

all accumulations of dust

• Comply with NFPA 51B

Employees and visitorsshould not carry smoking

materials in any areas wherecombustible dust is present!

Page 91: Unit 3

Controlling Ignition Sources• No propellant-actuated

tools unless machinery is

shutdown and cleaned

• Only non-sparking tools

used on machines where

combustible dust is

present

Page 92: Unit 3

• Do not dress grinding

wheels when the

collection ventilation is

on!

Controlling Ignition Sources

Page 93: Unit 3

Cleaning Tools

• Brooms & brushes natural

fiber bristles

• No synthetic bristles

• Scoops and dustpans, etc. to

conductive & non-sparking

• Do not return dry sweepings

to processing

Page 94: Unit 3

Proper PPE around Combustible Metal Dust• Except for working around

electricity, safety shoes should

be worn with

– Soles and heels attached by

sewing

– No nails or metal plates

– Safety toes composite or covered

– Shoes static dissipatingSpecialstatic

dissipating shoe

Page 95: Unit 3

Proper PPE around Combustible Metal Dust• Clothing clean, flame

retardant and non-static generating

• Tight fitting, smooth fabrics from which dust can easily be should be used

• No cuffs or other folds where aluminum could collect

• No wool or silk

Page 96: Unit 3

Proper PPE around Combustible Metal Dust• Emergency procedures for

clothing fires need to be implemented

• Use fire blankets where water is not allowed!

• Safety showers well away from dry aluminum powder

• Emergency procedures developed & implemented

Page 97: Unit 3

Compressed air & inert gas

• Don’t mistake plant

air for inert gas!

• Fittings for both shall

not be

interchangeable!

Page 98: Unit 3

Safety Inspections• Inspection program for

operations that produce dust!

• Performed on a regular

interval

• Skilled inspectors

• Reports filed

• Deficiencies corrected!

Page 99: Unit 3

Controlling Ignition Sources• Practice Quiz• 1. No smoking, cutting or welding in areas:

– A. Accumulations of dust are present.– B. Where wet aluminum is present.– C. Where powder actuated tools are approved.– D. All of the above.– E. A & B only.

• 2. Do not dress grinding wheels if:– A. If the ventilation system is turned off.– B. If the ventilation system is still turned on.– C. Neither A nor B.

Page 100: Unit 3

Controlling Ignition Sources• Practice Quiz• 1. No smoking, cutting or welding in areas:

– A. Accumulations of dust are present.– B. Where wet aluminum is present.– C. Where powder actuated tools are approved.– D. All of the above.– E. A & B only.

• 2. Do not dress grinding wheels if:– A. If the ventilation system is turned off.– B. If the ventilation system is still turned on.– C. Neither A nor B.

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Emergency Procedures• Practice Quiz• 3. Emergency procedures:

– A. For clothing fires needs to be implemented– B. Include fire blankets and their use where water is

not permitted.– C. Are often overrated and usually not necessary– D. A & B only.

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Emergency Procedures• Practice Quiz• 3. Emergency procedures:

– A. For clothing fires needs to be implemented– B. Include fire blankets and their use where water is

not permitted.– C. Are often overrated and usually not necessary– D. A & B only.

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PPE• Practice Quiz• 4. Clothing should be:

– A. Clean.– B. Non-static generating.– C. Flame Retardant.– D. All of the above.– E. B & C only.

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PPE• Practice Quiz• 4. Clothing should be:

– A. Clean.– B. Non-static generating.– C. Flame Retardant.– D. All of the above.– E. B & C only.

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Summary• In this section we discussed safe practices for

machining and finishing aluminum.• We identified the importance of safe means of

dust collection• We looked at housekeeping issues• Fire prevention and fire protection were also discussed• We also examined proper cleaning tools and the

correct PPE to wear when working around aluminum where combustible dust is present