The American University in Cairo

NFPA 45

FIRE PROTECTION FOR LABORATORIES USING

CHEMICALS

Purpose of the Standard

• This standard provides basic requirements for the protection of life and property in laboratory work where hazardous chemicals are handled through prevention and controls of fires and explosions.

• To protect personnel from the effects of toxic, corrosive, or otherwise hazardous chemicals to which they may exposed as a result of fire or explosion.

Definitions

• Educational Occupancies:• Building used for the gathering of 6 or more persons for

the purposes of instruction, such as schools, universities, colleges, and academies.

• Laboratory Unit:• An enclosed space used for experiments or tests. It may

contain one or more separate laboratory work areas.A laboratory unit is classified as A, B, or C according to the quantities of flammable and combustible liquids.

Definitions

• Laboratory Work Area:• A room or space for testing, analysis, research, instruction,

or similar activities that involve the use of chemicals. This work area may or may not be enclosed.

• Hazardous Chemicals:• A chemical with one or more of the following hazard

ratings as defined in NFPA 704, Standard system for the identification of fire hazards of materials. Health-2,3, or 4; Flammability 3 or 4; Reactivity 2, 3, or 4.

Laboratory Unit Fire Hazard Classification

Excl. quant. In cabinets and cans

Excl. quant. In cabinets and cans

Incl.. quant. In cabinets and cans

Incl.. quant. In cabinets and cans

Lab. Unit Class

Flam. Or Comb. Class

Unsprink Sprink. Unsprink Sprink.

Class A High Hazard

I

I, II, and IIIA

300 gal.

400 gal.

600 gal.

800 gal

600 gal.

800 gal.

1200 gal.

1600 gal.

Class B Interm. Hazard

I

I, II, and IIIA

150 gal

200 gal.

300 gal.

400 gal.

300 gal.

400 gal.

600 gal.

800 gal.

Class C Low Hazard

I

I, II, and IIIA

75 gal.

100 gal.

150 gal.

200 gal.

150 gal.

200 gal.

300 gal.

400 gal.

Explosion Hazard Classification

• A laboratory work area shall be considered to contain an explosion hazard if:

• 1- Storage of materials with a reactivity hazard rating of 4.

• 2- Use or formation of materials with reactivity hazard rating of 4.

• 3- Highly exothermic reactions such as polymerizations, oxidations, nitrations, peroxidation, hydrogenation, or organo-metalic reactions.

Construction Notes

• Laboratories will be classified (NFPA 101) as : Business – Health Care, Industrial

• Compartmentation of each laboratory unit is achieved by providing: (One-hour rated separation from adjacent labs or other areas. – Self-closing fire doors with at least ¾ hour rating.

• Two or more exits must be provided for labs of 200 feet area or more.

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• Doors to corridors from laboratories must swing in the direction of exit.

• When central supply of flammable, combustible or oxidizing gases is provided, shut-off valves in accessible locations must be provided, in addition to those at the points of supply and use.

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• Controls for air, gas, and other utilities must be color coded and labeled.

• GFCI on electrical outlets within 6 feet of all sinks.

Laboratory Unit Layout

Fire Protection

• Portable fire extinguishers

• Fire alarm systems

• Evacuation and emergency plans.

• Automatic extinguishing systems (sprinkler system).

• Inside standpipe and hose systems.

Lab Ventilating Systems

• Haz. Chemicals shall not be recirculated.• Location of fresh air intakes – avoid

drawing of hazardous chemicals from labs.• Negative pressure in the labs relative to the

corridors or adjacent non-labs areas.• Location of air supply diffusion devices to

avoid air current (hoods, exhaust system, and fire detection or ext. systems)

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• Min. 6 air change per hour – fume hoods.

• Open use of hazardous chemicals – 10 or more air change per hour.

• Exhaust ducts – negative pressure.

• Hoods air velocity : 80 – 100 fpm

• Local exhaust systems (elephant trunks or snorkels.

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• Exhaust ducts to outside the building – roofs 10 feet above roof level.

• Lab hoods shall be located in areas of minimum air turbulence.

• Lab hoods shall not be located adjacent to a single means of access to an exit or high traffic areas.

Chemical Storage & Disposal

• Hazardous chemicals – minimum necessary• Segregation of incompatible materials.• Dating of the first opening – 6 months

testing and evaluation and disposal.• Class I transference – bonding and

grounding.• Classification of chemical wastes.• No disposal of chemical wastes to the sink.

Maximum Allowable Container Capacity

Flammable Liquids

Flammable Liquids

Flammable Liquids

Combustible Liquids

Combustible Liquids

Container Types

IA IB IC II IIIA

Glass

Metal

Safety Cans

Metal Drums

1 pt

1 gal

2 gal

N/A

1 pt

5 gal

5 gal

5 gal.

1 gal

5 gal

5 gal

5 gal

1 gal

5 gal

5 gal

60 gal

5 gal

5 gal

5 gal

60 gal

Compressed and Liquefied Gases

• Manual shutoff valves at each point of supply and each point of use.

• Permanent piping shall be identified with the name of material.

• Cylinders of gases having health hazard rating of 3 or 4 shall be kept in ventilated hood or other continuously mech. Ventilated enclosure.

Maximum quantity and size limitations for comp. Gas

cylindersFlamm.

Gases and/or oxygen

Flamm. Gases and/or

oxygen

Liquefied flamm. gases

Liquefied flamm. gases

Gases with health

hazards ratings of 3

or 4

Sprinklered Space

Unsprinkl. Space

Sprinklered Space

Unsprinkl. Space

Max. # of cyl. Per 500

ft² or less

Max. Cylnder Size

(inches)

6

10 X 50

3

10 X 50

3

9 X 30

2

9 X 30

3

4 X 15

Lab Operations and Apparatus

• Automatic shutdown – unattended lab operations.

• Refrigerators or freezers for flam. Substances: Class I, Division 1 locations inside the ref.

• Outside the ref. : Class I, Division 2.• Over-temp shutoff switches for electrically

heated equipment.