Engineering Controls & Laboratory Design

“A safe, healthful, and secure environment for scholarship and research.”

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Advanced Laboratory Safety TrainingPart 4 of Texas A & M Laboratory Safety Training Programs

Key Concepts

• Types of Laboratories• Design of Laboratories

– Engineering & Architectural Design of Laboratories

– Fire & Life Safety Design of Laboratories• Laboratory Control Systems

– Equipment & Furnishings– Storage– Ventilation Systems

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Types of Laboratories

• Academic vs. Industrial• Research vs. Instructional• Similar functions housed together

vs. building for entire departments

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Engineering and Architectural Principals

Laboratory buildings present difficult challenges– Very little assignable space (65%)– Energy hog, air conditioning, electrical needs,

services, fire protection & life safety issues– Architects must balance beauty with safety– Engineers must balance conserving energy with

safety– Both must balance users needs and cost with

safety

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Organizations Regulating Laboratory Design

• Southern Building Code (SBC)• Building Officials and Code Administrators (BOCA)• National Fire Protection Assoc (NFPA)• Standard Fire Protection Codes

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Basic Life Safety Design Components

• Labs should be designed to provide at least 1, & usually 2 clear exits

• Building should have at least two clearly marked exits at opposite ends of the building for occupancies up to 500 persons (3 for 500-1000)

• Doors must swing in the direction of the exit travel

• Travel distance to an exit must not exceed 200’ without fire suppression, or 250’ with fire suppression

• 1 hour fire rated corridors, stairwells

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Basic Life Safety Design Components

• Storage not permitted in the above areas • Self-closures on doors• Areas of refuge• Americans with Disabilities Act (ADA)

compliance issues (e.g. ramps)• Emergency power for signs, lights, equipment• Chemical Storage room requirements

– Class I Division 2 requirements (normally contained flammable liquids)

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Fire Systems: Protection & Detection

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Other Issues — Equipment• Backflow prevention on the clean water

(potable) side• Contamination can occur during pressure

differentials of a piece of tubing in a sink under water - flush several toilets and the pressure drops on the dirty side causing a back flow of water

• Chemical resistant casework, typically with an epoxy coating

• Local exhaust ventilation for equipment, processes

• Emergency eyewashes & safety showers– Must be tempered and require no more than 10

seconds to reach

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Other Issues — Equipment

• Vacuum & air compressor issues• Waste issues• Flammable storage cabinets• Acid storage cabinets• Glove boxes• Biological safety cabinets

– Class I-III (glove boxes) partial to 100% exhaust

• Compressed gas storage

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Other Issues — Storage

• Flammable storage cabinets

• Acid storage cabinets

• Glove boxes

• Biological safety cabinets– Class I-III (glove boxes) partial to 100%

exhaust

• Compressed gas storage

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Ventilation

• All labs using chemicals require 100% outside air• The number of Air Changes per Hour (ACH) are

recommended by various organizations (American National Standards Institute, American Society Heating Refrigeration, Air Conditioning Engineers, (National Fire Protection Association, OSHA)

• Because of the requirement for 100% outside air and the number of exhaust point and exhaust volume mechanical systems are one of the largest costs

• Variable air volume systems were designed to minimize these cost

• Constant air volume hood systems with set backs

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Types of Hoods

• Constant Air Volume• Variable Air Volume (VAV) • Auxiliary Air• Recirculated Air (bad)

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Constant Air Volume Hoods• Known also as bypass hoods• Face velocity changes as sash is opened but total exhaust

remains constant

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Variable Air Volume Hoods

• Maintain a constant face velocity independent of the size of the sash opening

• Tracks room pressurization to fume hood exhaust to ensure that the room is kept under negative pressure

• Manifold system, with redundant fans• Reduces possibility of reentry of contaminated

air into building

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Variable Air Volume Hoods Disadvantages

• Initial cost high• Many control points to track, potential for malfunction• Difficulty in maintaining sophisticated controls• When the system goes down, the entire building is not

exhausted• Potential cost savings by allowing a reduction of supply

air when sash is shut– Hoods exhaust 1000-1200 cfm– 8-10 ach, at $6-8/cfm of conditioned air can get very

expensive

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Auxiliary Air Hoods

Supply auxiliary air (extra air) to help improve ventilation

Advantages– Unconditioned air is deposited into the hood at the

face– Saves on conditioned make-up air

Disadvantages– Researcher is either cold or hot while standing at the

hood– Requires a separate supply system– Difficult to balance, maintain containment

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Recirculated Air Fume Hoods

• Re-circulate fumes after passing air through a filter

• Should never be used due to increased risk of exposure to contaminants potentially remaining in the filtered, re-circulated air

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EXAMPLE: Laboratory Ventilation SystemShowing air supply input, air flows, and exhaust

Laboratory Ventilation System

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EXAMPLE: A Typical Laboratory Fume Hood

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Typical Laboratory Fume Hood

EXAMPLE: A Typical Laboratory Fume HoodShowing Worker Position

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EXAMPLE: A Typical Walk-In Type Hood

EXAMPLE: A Typical Walk-in Laboratory Fume Hood Showing Worker Position22

EXAMPLE: Single Hood - Single Fan CAV System

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EXAMPLE: Multiple Hood - Single Fan CAV System

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EXAMPLE: Multiple Hood - Multiple Fan VAV System

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Minimum Hood Standards

• All hoods must be tested to the ANSI//AIHA Z9.5 Standard – Requires

1. a manufacturers test2. as installed test3. as used test

– Minimum face velocity must be 80-120 fpm, optimum 100 fpm at 18” sash opening

– Flow monitors must be installed on all new hoods with a visual or audible alarm

• ANSI/ASHRAE 110 Standard– Smoke visualization and tracer gas tests are

recommended to identify hood performance and containment efficiency

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Hood Installation

• Fume hoods should be placed in the back corner of the room away from exit doors, turbulence and diffusers

• Not near the means of egress• Away from windows

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Clean, but Crowded. Do not store items in the hoods. Do not obstruct access to the hood with equipment placement.

“Could Be Better” Lab Designs

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“Could Be Better” Lab Designs

Sash Left Open; Improper Storage in Hood; Access obstructed.

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“Could Be Better” Lab Designs

Clean & neat, but hood sashes were left open.

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“Could Be Better” Lab Designs

Cluttered; improper storage; access obstructed; poor housekeeping.

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“Could Be Better” Lab Designs

• Improper storage in the hood

• Sash left open• Clutter in walkway• Clutter on top of

oven (on right)

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“Could Be Better” Lab Designs

Unacceptable! Needs extensive repair or replacement! Rusty & deteriorated structure & apparatus; sash left open; cords & hoses through sash; improper storage in hood

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On the Roof

Example of fans, motors & exhaust discharge above the lab building roof.

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On the Roof

Example of fans, motors & exhaust discharge above the lab building roof.

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On the Roof

Example of fans, motors & exhaust discharge stacks above the lab building roof.

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On the Roof

Example of fans, motors & exhaust discharge above the lab building roof.

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Chemical Storage Cabinets

“A safe, healthful, and secure environment for scholarship and research.”

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Flammable Storage Cabinets

• Flammable and corrosive cabinets are typically the bottom supporting structure of the fume hood

• They can be vented or non-vented enclosures, used primarily for storage of flammable or corrosive materials

• If vented, the flammable storage cabinet is connected to the hood exhaust

• Free-standing chemical storage cabinets are more common, and are often the preferred storage option

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Example: Typical Flammable Storage Cabinet

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Corrosive Material Storage Cabinets

• The corrosive storage cabinet should be designed with a protective lining and secondary containment to inhibit chemical corrosion

• Corrosive storage cabinets should be vented either through the hood or through their own dedicated exhaust

• Stored Acids and Bases must be segregated or separated

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EXAMPLE: Specialty Storage Cabinets

Paint & Ink Storage Cabinet Pesticide Storage Cabinet

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Laboratory Ventilation:Chemical Fume Hood Guide

“A safe, healthful, and secure environment for scholarship and research.”

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Key Concepts

• Be Familiar with the Three (3) Common Types of Fume Hood̶ Constant air volume (CAV)̶ Variable air volume (VAV)̶ Specialty laboratory exhaust systems

• Minimize potentially harmful chemical exposure to laboratory workers, by conducting ALLchemical work inside a properly functioning fume hood

• Never use the fume hood for storage!

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Laboratory Fume Hoods• The first defense to minimize chemical exposure to

laboratory workers• The primary means of protection from inhalation of

hazardous vapors• All potentially harmful chemical work must be conducted

inside a properly functioning fume hood • To ensure safety, all fume hoods should be inspected

annually • There are many types of hoods, each with its own design

and function • Common Types of Fume Hood

– Constant air volume (CAV)– Variable air volume (VAV)– Specialty lab exhaust systems

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Type of Hoods Using Constant Air Volume

• Conventional hood• Conventional hood without a bypass• Conventional bypass fume hood• Auxiliary air hoods

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Conventional Hoods• A properly functioning fume hood is one of the most important pieces of

laboratory safety equipment• A chemical fume hood can protect workers from inhaling chemical fumes by

constantly pulling contaminated air into the hood and exhausting it out of the building

• A fume hood can also protect users in case of a fire or explosion by helping to physically contain the event

• A conventional fume hood is designed with an adjustable sash which can be raised and lowered in front of the user's face

• These traditional fume hoods use constant air volume (CAV) exhaust fans, which exhaust air from the hood at a constant rate, regardless of sash height– This simple design can result in unacceptably high air velocities at the face of the

fume hood when the front sash is lowered and nearly closed• The most common fume hood is the constant volume conventional hood • This hood is enclosed on three sides, and has a sash that slides in the front

– The sash can go up or down, which determines the hood's performance and face velocity

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Conventional Hood• This term is used to describe a constant air

volume (CAV) hood, an older, traditionally less elaborate hood design used for general protection of the worker

• Because the amount of exhausted air is constant, the face velocity of a CAV hood is inversely proportional to the sash height

• That is, the lower the sash, the higher the face velocity

• CAV hoods can be installed with or without a bypass provision which is an additional opening for air supply into the hood

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EXAMPLE: Typical Laboratory Fume Hood

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EXAMPLE: Typical Laboratory Fume Hood

Basic Air Flow into the Fume Hood

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EXAMPLE: Typical Laboratory Fume Hood

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EXAMPLE: Typical Laboratory Fume Hood

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EXAMPLE: Typical Laboratory Fume Hood

Chemical StorageIn

Base Cabinet

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EXAMPLE: Typical Laboratory Fume Hood

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EXAMPLE: Typical Laboratory Fume Hood

Air Flow Paths and Turbulence in the Hood Varies with Sash Height

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Up on the Roof

Exhaust fan motors pull contaminated air from the hood & the laboratory to exhaust stacks, air scrubbers and/or filters located on building roof tops.

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Conventional Hood: Without a Bypass• Conventional hoods consist of an enclosed cabinet

with a connection for an exhaust duct and a movable sash on the front

• Some conventional hoods do not have a provision for a bypass

• A conventional bypass fume hood is an improved design, featuring a protected, secondary air intake above the sash face area – This air intake gradually opens as the sash is lowered, thereby

limiting the velocity of air flowing under the sash into the hood – This allows for a consistent removal of air from the lab

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Conventional: Bypass Fume Hood• The bypass fume hood is an improved variation on the

conventional fume hood• The bypass is located above the sash face opening and

protected by a grille which helps to direct air flow• The bypass is intended

to address the varying face velocities that createair turbulence leading to air spillage

• The bypass limits theincrease in face velocity as the sash nears the fully closed position, maintaining a relatively constant volume of exhaust air regardless of sash position

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Auxiliary Air Hood• Also referred to as a makeup air fume hood• Developed as a variation on the bypass fume hood and reduces the amount of

conditioned room air that is consumed • The auxiliary fume hood is a bypass hood with the addition of direct auxiliary air

connection to provide unconditioned or partially conditioned outside makeup air• Auxiliary air hoods were designed

to save heating and cooling energycosts, but tend to increase the mechanical and operational costs due to the additional ductwork, fans, and air tempering facilities

• In general, installation of this type of hood is discouraged since the disadvantages usually outweigh the benefits

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Variable Volume Air Principle

• Variable air volume (VAV) hoods differ from constant air volume (CAV) hoods because of their ability to vary air volume exhausted through the hood depending on the hood sash position

• VAV hoods are becoming the preferred hood due to the elimination of excess face velocity that can generate turbulence leading to contaminated air spillage, endangering the worker

• They also reduce the total quantity of supply and exhaust air to a space when not needed, thereby reducing total operating costs

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Variable Air Volume (VAV) Hood

• A VAV hood maintains a constant face velocity regardless of sash position

• To ensure accurate control of the average face velocity, VAV hoods incorporate a closed loop control system

• The system continuously measures and adjusts the amount of air being exhausted to maintain the required average face velocity

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Variable Air Volume (VAV) Hood

• The addition of the VAV fume hood control system significantly increases the hood's ability to protect against exposure to chemical vapors or other contaminants

• Many VAV hoods are also equipped with visual and audible alarms and gauges to notify the worker of hood malfunction or insufficient face velocity

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Specialty Lab Exhaust Systems

• Walk-in Hood• Fume Exhaust Connections: “Snorkels”• Canopy Hoods• Glove Boxes• Perchloric Acid Hoods• Radioisotope Fume Hoods• Distillation Hoods

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Walk-in Hoods• A walk-in hood is a hood which sits directly on the

floor and is characterized by a very tall and deep chamber that can accommodate large pieces of equipment

• Walk-in hoods may be designed as – Conventional– Bypass– Auxiliary air– VAV

• If you have a walk-in hood, contact your safety officer for operating protocol and inspection procedures

• Walk in fume hoods are basically a ventilated room with an air baffle at the back and adjustable slots to insure laminar flow

– Access is normally gained by sliding or folding doors• Walk in fume hoods are mainly used to set up large

scale experiments or processes, experiments are erected in the walk in fume hood, the doors are closed and the experiment is monitored or controlled remotely

• No protection is provided to persons while inside the walk-in fume hood

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Fume Exhaust Duct Connections

• Commonly called “snorkels”, “elephant trunks,” or “flex ducts”

• Designed to be somewhat mobile allowing the user to place it over the area needing ventilation

• However for optimal efficiency, these connections must be placed within six (6) inches of an experiment, process, or equipment

• These funnel-shaped exhausts aid in the removal of contaminated or irritating air from the lab area to the outside

Extracting lead solder fumesusing Snorkel.

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Canopy Fume Hoods• Canopy hoods are horizontal enclosures

having an open central duct suspended above a work bench or other area

• Most often used to exhaust areas that are too large to be enclosed within a fume hood

• The major disadvantage is that the contaminants are drawn directly past the user's breathing zone

• Designed to vent non-toxic materials such as heat, steam and odors from large or bulky apparatus such as ovens, steam baths and autoclaves

• May be wall-mounted or suspended from the ceiling

• Built-in baffles to increase air velocities and enhance overall capture efficiency

• Similar to a kitchen stove exhaust hood

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Glove Boxes

• Glove boxes are used when the toxicity, radioactivity level, or oxygen reactivity of the substances under study pose too great a hazard for use within a fume hood

• The major advantage is protection for the worker and the product

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Perchloric Acid Fume Hoods• Perchloric acid fume hoods are to be

installed and used whenever process involving the production of perchloric acid fumes

• This type of hood is designed to prevent the deposition and build up of perchloric salts on the hood or duct surfaces

• Perchloric acid hoods are designed with wash down devices which periodically (after each use) rinse the fans ducts and fume hoods surfaces with water

• The fume hood and duct work is made of stainless steel and the duct work is kept straight, vertical and seamless as possible to aid in washing away perchloric salts

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Perchloric Acid Fume Hoods

• Heating perchloric acid should be undertaken with extreme caution

• Do not use oil baths or open flames to heat perchloric acid

• Do not dry filter paper used to collect perchloric acid precipitates

• Keep perchloric acid away from organic chemicals, especially alcohols and glycerol

• Store perchloric acid in glass or ceramic trays

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Perchloric Acid & Radioisotope Fume Hoods

• Both perchloric acid and volatile radioisotope work require specific fume hood use protocols

• If you have questions or concerns about working with perchloric acid or volatile radioisotopes within a fume hood, immediately contact your Safety Officer or call EHS 845-2132 for further guidance

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Fume Hood Design Definitions

• Sash• Alarms, Sensors, Controls,

and Gauges• Air Foil (Sill)• Air Jambs• Baffles

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Sash• The movable glass panel that

covers the face area of a fume hood

• Sashes can be vertical, horizontal, or a combination of the two

• Many hoods are installed with a sash stop, which stops the sash at approximately a 14 inch work level

• Sash stops should never be removed, overridden, or modified

• All lab work in a properly functioning fume hood be performed at the sash stop level or lower, whenever possible Sash

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Alarms, Sensors, Controls, Gauges

• New hoods are installed with alarms, sensors, air flow controls, and gauges

• These features are included to provide lab personnel with a constant reading of fume hood performance

• If the face velocity falls below an acceptable work range the hood sensors will trigger an alarm to notify lab personnel Alarms, Sensors, Controls, Gauges

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Alarms, Sensors, Controls, Gauges

• Hoods usually go into alarm mode either because– The sash has been raised to a height at which

the hood can no longer exhaust a sufficient amount of air

– The building air exhaust system is not working properly

– There has been a power outage

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Alarms, Sensors, Controls, Gauges

• When a hood alarms, no chemical work may be performed until the exhaust volume is increased

• Additionally, lab workers should not attempt to stop or disable hood alarms

• The university Physical Plant office should be notified for adjustment of air handling system exhaust and fume hood maintenance

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Air Foil (Sill)• The air foil or sill, located at the front of the hood beneath the

sash, creates a smooth air flow, minimizing turbulence of the air entering the hood

• The recessed work area is directly behind the sill • All work should be done at least six (6) inches into the recessed

area

Air Foil Bypass Air Foil Variable Air Foil Add Air

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Air Jambs

• Air jambs are vertical sills or side posts at the front of the hood

• These are tapered to promote smooth air flow into the hood

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Chemical Fume Hood Baffles• Baffles are movable panels located on the back wall of the

hood, that create slots in which air is exhausted • The pattern of the air moving into and through the hood is

determined by the setting of the baffles• Adjust the baffles according to the specific gravity of the

chemicals used in the hood• Once the baffles are set, they should not be re-adjusted by

lab personnel

Good Fair Poor

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Fume Hood Operating Performance

• Location• Face Velocity• Air Flow Indicators• Inspection

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Fume Hood Location• The location of the fume hood affects its

efficiency• Ideally, fume hoods should be located in an

area of minimal traffic

• When a person walks by a fume hood, turbulence can be created causing contaminants to be drawn outside the hood

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Fume Hood Location

• Also, if the air diffuser is located directly above the fume hood, air turbulence may be created causing contaminants to escape into the room

• The air flow into the room has an effect on the fume hood

• All doors should be closed to maintain the negative pressure of the lab with respect to the corridor

• This ensures that any contaminants in the lab will be exhausted through the fume hood and not escape into the hallway

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Face Velocity• The average velocity at which air is drawn through the

face opening to the hood exhaust • The acceptable range of the average face velocity is

60-100 feet per minute (fpm) • The current NFPA-45 specifies hood face velocity at

100 fpm with a low flow alarm• The face velocity measurement should be:

100 fpm ± 10 linear feet per minute of air flow• If non-carcinogenic materials are being used the

acceptable face velocity for minimally hazardous materials is 50 fpm

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Face Velocity

• The ideal average face velocity is 100 fpm for most operations

• Hoods installed today are at 100 fpm as the industry norm and for Fire Code compliance

• If using a carcinogen, reproductive toxin or acutely toxic material, it is recommended that the face velocity range from 60 to 125 fpm

• At velocities greater than 125 fpm, the creation of turbulence causes contaminants to flow out of the hood and into the user's breathing zone

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Air Flow Indicators

• Small pieces of tinsel are taped to the bottom corner of the sash

• Inward movement of the tinsel indicates air is being drawn into the hood

• Air flow indicators do not determine face velocity• They only indicate that air is being exhausted

through the fume hood

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Inspection of Fume Hoods• When installed, fume hoods should be inspected in accordance

with ASHRAE 110 to ensure proper ventilation– ASHRAE is the American Society of Heating, Refrigerating and Air-

Conditioning Engineers• ASHRAE 110 is the industry standard tracer gas mannequin

method • It is the responsibility of the university to arrange for testing and

certifying the hood Call 845-2132 to schedule hood testing

• An air balancing specialist ensures that face velocities meet design criteria and that supply and exhaust air flow are in proper proportion to establish a negative pressure differential between the lab and the outside corridor

• Exhaust flow must be greater than supply to create air movement from the hall into the lab to contain airborne contaminants

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Inspection of Fume Hoods• Ideally, a random sample of chemical hoods can be tested

for leakage and proper capture integrity• A tracer gas such as sulfur hexafluoride is delivered into

the hood• Measurements of concentration are collected around the

hood to determine gas escape• A mannequin is placed at the face of a hood to simulate

an operator's presence• Texas A&M University inspects chemical fume hoods

annuallyCall 845-2132 to schedule hood inspections

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Inspection of Fume Hoods• Inspect fume hoods annually• 10% of all VAV hoods on a single system may be tested and

averaged to determine the overall efficiency for all VAV hoods on that system

• All conventional hoods and specialty hoods are inspected individually

• After initial post-installation checks, inspect fume hoods annually for the following– Average face velocity of the hood with the sash fully opened– Sash height at which the average face velocity is 100 fpm– Smoke test to determine air flow patterns and leakage– Placement of airflow indicators in hood– Survey hood condition for spills, airflow blockage, and

disabled sash stops

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Safe Work Practices• Do not use the fume hood as a storage area• Do not keep equipment and chemicals unnecessarily in the

hood – May cause airflow blockage

• Do not use the hood as a waste disposal mechanism (e.g., for evaporation of chemicals)

• Do not override or disable mechanical stops on the sash.• Do not place your head inside the hood • Do not make rapid movements in front of the hood including

opening and closing the fume hood sash rapidly and/or swift arm and body movements in front of or inside the hood– Such movements may increase turbulence and reduce the

effectiveness of fume hood containment

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Safe Work Practices: Rules

• Keep fume hood exhaust fans on at all times• Perform all work at least six inches inside the hood• Keep the hood sash closed as much as possible at

all times to ensure the optimum face velocity and to minimize energy usage

• Keep laboratory doors closed to ensure negative room pressure to the corridor and proper air flow into the hood

• Keep the slots of the baffle free of obstruction

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Safe Work Practices: Rules• The health & safety of laboratory personnel and building

occupants must be the primary goal of laboratory management

• Properly functioning fume hoods provide protection from the hazards of chemical vapors and other harmful airborne substances

• Substitute toxic chemicals with less hazardous materials whenever possible

• Train and educate employees regarding specific hazards and include work methods that help reduce contaminant exposure

• Have a general awareness of the operation of your hood and be aware of any differences in visual or audible cues that may imply a change in function

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Unsafe Hood Use: Prohibited

Never Use the Fume Hood for Chemical Storage!

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Unsafe Hood Use: Prohibited

Never use the fume hood for storage or as a computer work station!

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Unsafe Hood Use: Prohibited

Never climb inside the fume hood!

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Inspection of Fume Hoods

Contact your safety officer immediatelyif the fume hood is not functioning properly.

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Hazard Evaluation & Risk Assessment

“A safe, healthful, and secure environment for scholarship and research.”

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Key Concepts

• Hazard• Hazard Assessment• Risk• Risk Assessment• Risk Management• Risk Communication• Acceptable Risk• Project Safety Analysis (PSA)

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What is Risk?

• The potential for realization of unwanted, adverse consequences to human life, health, property, or the environment

• Estimation of risk is usually based on the expected value of the conditional probability of the event occurring times the consequence of the event given that it has occurred

• Risk is the probability or chance that the hazard posed by a substance or item will lead to injury, loss or harm

• Thus, risk is the probability of injury, loss or harm resulting from unprotected exposure to a hazard

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Risk Analysis

• A detailed examination including risk assessment, risk evaluation, and risk management alternatives

• Performed to understand the nature of unwanted, negative consequences to human life, health, property, or the environment

• An analytical process to provide information regarding undesirable events

• The process of quantification of the probabilities and expected consequences for identified risks

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Risk Assessment

The process of establishing information regarding acceptable levels of risk for an individual, group, society or the environment.

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Risk Estimation

• The scientific determination of the characteristics of risks, usually in as quantitative a way as possible

• These include the magnitude, spatial scale, duration and intensity of adverse consequences and their associated probabilities, as well as a description of the cause and effect links

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Risk Evaluation

A component of risk assessment in which judgments are made about the significance and acceptability of risk.

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Risk Identification

• Recognizing that a hazard exists and attempting to define its characteristics

• Often risks exist and are even measured for some time before their adverse consequences are recognized

• In other cases, risk identification is a deliberate procedure to review, and help anticipate possible hazards

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Safety

• Relative protection from adverse consequences

• Identifying hazards, and reducing the potential risks of such hazards to acceptable levels

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Hazard

• A condition or physical situation with a potential for an undesirable consequence, such as harm to life or limb, or damage to facilities or the environment

• Something with the potential to cause harm

• A source of danger• Implies great and continuous risk of harm

or failure

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Hazard Assessment

An analysis and evaluation of the physical, chemical and biological properties of a hazard.

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Risk vs. Hazard• The term "risk" is often confused with "hazard"• A high voltage power supply, a sample of radioactive metal, or

a toxic chemical may present a hazard, meaning that they present the potential for harm

• Concentrated acids clearly present a hazard to the user of serious burns if they are handled incorrectly

• It is thus evident that hazards are something we can do little about

• The hazards posed by a carcinogen, a concentrated acid or an explosive substance are inherent properties of the material

• The risks they pose, however, can be (and should be!) minimized by initially preparing a suitable risk assessment and safety analysis, and then following the procedures established in that assessment to ensure that the risks are reduced to acceptable levels

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Culture of Chemical SafetyPublic opinion of chemicals has changed over the last 40 years• Love Canal, 1977 – increased America’s

awareness of the consequences of unrestricted disposal of hazardous material/wastes– Love Canal is a neighborhood in Niagara

Falls, NY, which became the subject of national attention and controversy following the discovery of toxic waste buried beneath the neighborhood

• Increased rates of health effects including birth defects, miscarriages, epilepsy, etc.

• Lead the U.S. EPA to declare a federal emergency, relocate residents, and close the neighborhood for cleanup

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Culture of Chemical SafetyDesignation of Superfund Sites

• “Superfund” is the common name for the U.S. environmental policy known as the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), which was enacted by congress in Dec-1980 in response to the Love Canal disaster

• CERCLA was created to protect people, families, communities and others from heavily contaminated toxic waste sites that have been abandoned

• Federal fund for cleanup, decontamination and restoration of such sites

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Culture of Chemical SafetyCERCLA, Title III, implemented “Community Right-to-Know” laws

• Required employers to report their hazardous substances to local authorities, to inform the public and aid in emergency preparedness planning

• Resource Conservation & Recovery Act (RCRA)– Implemented “Cradle-to-Grave” management of waste programs– The generator of wastes is held responsible for such wastes from

“cradle-to-grave”109

Culture of Chemical Safety

On Dec. 3, 1984, a Union Carbide chemical plant in Bhopal, India, released a deadly cloud of the gas, methyl isocyanate, into the air, killing at least 6,500 people

• Resulted in OSHA’s Standard for Process Safety Management (PSM) of highly hazardous chemicals

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Annual Risk of Death in U.S.

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Risk Comparisons For Involuntary Risks

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Concept Of De Minimis Risk

• De Minimis risks are those risks judged to be too small to be of significant social concern, or too small to justify the use of risk management resources for control

• The De Minimis risk level frequently used by government agencies (EPA, FDA) is 1 in 1,000,000 or “1 in a million” increased risk of an adverse effect occurring over a 70-year lifetime in a large population

• The “1 in a million” risk level used to regulate some chemicals and other hazards is many times below risks which people face every day

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One in a MillionRisks That Increase Probability Of Death By One In A Million

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Reality Check

“There is no point in getting into a panic about the risks of life until you have compared the risks which worry you with those that don’t, but perhaps should.”

- Lord Rothschild, The Wall Street Journal, 1979

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Principle Elements of Risk Assessment

• Anticipation• Recognition• Evaluation• Control

These are also the principle Industrial Hygiene elements

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Risk Assessment vs. Risk Management

• Anticipation, Recognition and Evaluation are Risk Assessment

• Control and Support are Risk Management

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Risk

Risk is an Equal Function of Toxicity and Exposure

Risk = Toxicity X Dose

Exposure = Dose

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Paracelsus Understood Risk Assessment

• Paracelsus, sometimes called the father of toxicology, wrote:– “Alle Ding sind Gift, und nichts ohn Gift; allein die

Dosis macht, daﾟ ein Ding kein Gift ist.” (German)“All things are poison and nothing is without poison, only the dose permits something not to be poisonous. Thus, the dose makes the poison”

• Substances often considered toxic can be benign or beneficial in small doses, and, conversely, an ordinarily benign substance can be deadly if over-consumed– Even water can be deadly if over-consumed– Many beneficial medicines can have harmful

effects when taken in incorrect doses

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Risk Communication

• Interacting and communicating risk information and risk management plans with affected populations

• The likelihood of achieving a successful risk communication program increases with your knowledge of those with whom you are communicating

• Early in the process, know who the affected populations are, what their concerns are, how they perceive risk, and whom they trust

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The 7 Cardinal Rules of Risk Communication

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Risk PerceptionPeople's perceptions of the magnitude of risk are influenced by factors other than objective, numerical data.

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Acceptable Risk

• The concept of Acceptable Risk is not particularly easy to define

• It is essentially a measure of the risk of harm, injury or disease arising from a chemical or process that will be tolerated by a person or group

• The safety goal is to identify hazards, assess their risks, and implement appropriate controls to reduce such risk to acceptable levels

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Acceptable Risk

• Whether a risk is "acceptable" will depend upon the advantages that the person or group perceives to be obtainable in return for taking the risk

• Whether they accept whatever scientific and other advice is offered about the magnitude of the risk, and numerous other factors, both political and social

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Absolute Risk

The excess risk due toan exposure to a hazard

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Relative Risk

• The risk of harm among a population exposed to a potentially damaging substance, compared to the risk amongst an unexposed population

• Also be called the "risk ratio" or the "odds ratio" • Relative risk may also be used to describe ratio of

the cumulative incidence rate in the exposed population to the cumulative rate in the unexposed population

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Risk Phrases

• Risk phrases, coded in the form R34, R61, etc., are now included in SDS sheets for chemicals purchased in the UK and in many other countries

• A list of the R-phrases is available at Wikipedia.org

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Physical Hazard

• A Physical Hazard arises when use of a substance is potentially dangerous – Due, for example, to the possibility of explosion,

fire or violent reaction with water• Peroxides, sulfuric acid, diethyl ether and

phosphorus pentachloride are examples of materials which present physical hazards

• Often, such materials will also present health hazards due to their toxicity

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Chronic Hazard

• A Chronic hazard is presented by a substance which has the potential to cause long-term damage to health, often as a consequence of repeated or prolonged exposure to it

• Typically, a chronic effect results from long-term, repeated exposures to small amounts

• Chronic illness typically develops gradually from long-term, repeat exposures, and leads to debilitating disease and, eventually, death

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Acute Hazard

• An Acute hazard is presented by a substance with potential to cause immediate damage to health

• An Acute effect is one which involves severe symptoms which develop rapidly, and may quickly reach a crisis

• Typically results from short-term, or even a single, exposure to the hazard

• Acute Illness typically results in recovery to full or partial health, or to death

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Other Hazards

Hazard, Kentucky• A city in southeastern Kentucky• The seat of Perry county• Founded in 1821 • Originally named for the American

naval hero Commodore Oliver Hazard Perry

• It lies on the North Fork Kentucky River in the Cumberland foothills just east of Daniel Boone National Forest (Redbird Purchase Unit), 118 miles (190 km) southeast of Lexington

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Commodore Oliver Hazard Perry

• Born Aug. 20, 1785, In Rhode Island

• Died Aug. 23, 1819, at sea near Trinidad (age 34), of yellow fever

• U.S. naval officer who became a national hero when he defeated a British squadron in the Battle of Lake Erie in the War of 1812

• “We have met the enemy and they are ours...”

• “Don’t give up the ship.”

Ensuring Safe Laboratories via PSA • The following processes must occur prior to conducting all

laboratory research, during project planning & design – Identify hazards – Assess risks– Plan controls

• Project Safety Analysis (PSA)– A formal, participative process for identifying hazards

associated with a particular project or facility, assessing the risk of these hazards, and selecting appropriate control methods to reduce the risks to acceptable levels for safe, creative and successful outcomes

– Required for all projects within TEES and the TAMU College of Engineering, with significant risk potential

– For information and guidance call 845-2132 ask to speak with the Engineering Safety Officer

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Incident Notification & Reporting

“A safe, healthful, and secure environment for scholarship and research.”

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Key Concepts

• Types of Environmental Health & Safety Incidents• Notify Your Supervisor…• Injury or Illness at Work• Workers Compensation Insurance• WCI “Employers First Report of Injury or Illness” form• Office of Engineering Safety• TEES Employees• TAMU Employees• Non-Employee Students and Visitors

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Environmental Health, Safety & Security Concerns

• Accident, Injury, Illness• Crisis, Disaster• Environmental issues• Fire, Explosion• Spill, Release (chemical, HazMat, etc)• Significant Near-Miss• Security Concerns

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Incident Notification Protocol for TEES• Notify Your supervisor or Department/Division Head ASAP !• Within 24 hours of incident occurrence, notify:

– Engineering Program Office (EPO)– Office of Engineering Safety (EHS)

• Required for TEES & COE investigation to:– Determine root causes– Identify controls to reduce risk & prevent recurrence

This protocol is required by…i. TEES Rule, 34.07.99.E1

Notification In Event of Emergency or Newsworthy Event

ii. System Regulation 34.07, Crisis Management

iii.The Engineering Safety Plan (Est. at Feb-1996; current revision at FY-2008)

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What to do if an TEES Employee gets injured?

• File WCI “Employer’s First Report of Injury and Illness” Required by:– TAMUS - Office of Risk Management– Texas Workers Compensation Insurance Division

• MUST be on file with TX-WCI within 7 days !

• What does it do?– Initiates a workers compensation insurance claim– Does NOT initiate incident investigation

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What to do if a TAMU Employee gets injured?

• File the WCI “Employers First Report of Injury or Illness” form from TAMU Human Resources for:– TAMU (university-only) Employees– Non-Employee Students & Visitors (Note: this form is different for TEES

Employees)

• Should be completed by the person’s immediate supervisor and faxed within 24 hours of the injury/illness (with the Witness Statement, if available) to:– TAMU Workers’ Compensation Office (WCO) Fax: (979) 847-8546

• Provide the employee with the 3-page handout titled Injured Worker Rights & Responsibilities

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Notification & Report Protocols

Notify: When:Responsible Faculty/PI Immediately

Department Safety Officer Immediately

TAMU Emergency Services (9-911 or 911) Immediately

Building Proctor Within 1 hour

Department/Division Head Within 1 hour

Manager, Engineering Safety ASAP

Employers First Report of Injury to TEES-HR Within 24 hours

In An Emergency!!!

• TAMU Emergency Medical Services or Police– Dial 911 immediately– Or, direct dial 845-2345

• From cell phone or non-campus phone, dial: 911• For Maintenance Emergencies, dial: 845-4311• TAMU Emergency Phone Numbers - Web Page:

http://www.tamu.edu/00/data/emerg.html

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Office of Engineering Safety

Environmental Health, Safety & Security Services

http://engineering.tamu.edu/safety/845-2132

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