Lab Safety

Flammable and Combustible Materials

What are flammable and combustible materials? 

Materials that are flammable or combustible can burn or ignite causing fire or other heat giving reactions.

The National Fire Protection Agency (NFPA) places flammable and combustible liquids in the following classes: 

 

Flash Point*

Boiling Point

Flammable

 

 

Class IA

< 73°F (22.8°C)

< 100°F (37.8°C)

Class IB

< 73°F (22.8°C)

>100°F (37.8°C)

Class IC

>73°F (22.8°C) <100°F (37.8°C)

 

 

 

 

Combustible

 

 

Class II

>100°F (37.8°C)&< 140°F (60°C)

 

Class IIA

>140°F (60°C)&< 200°F (93°C)

 

Class IIIB

>200°F (93°C)

 

*Flash Point is defined as the minimum temperature at which a liquid gives off vapor in sufficient concentration to form an ignitable mixture with air near the surface of the liquid.

 

Class A Class B Class C Class D
High Moderate Low Minimal

How do I handle flammable and combustible materials?

 When handling these materials you should always:

  • Eliminate ignition sources such as open flames, hot surfaces, sparks from welding or cutting, operation of electrical equipment, and static electricity
  • Assure appropriate fire extinguishers and/or sprinkler systems are in the area
  • Ensure there is proper bonding and grounding when it is required, such as when transferring or dispensing a flammable liquid from a large container or drum. Assure bonding and grounding is checked periodically
  • Do not heat flammable liquids with an open flame. Steam baths, salt and sand baths, oil and wax baths, heating mantles and hot air or nitrogen baths are preferable.
  • Minimize the production of vapors and the associated risk of ignition by flashback. Vapors from flammable liquids are denser than air and tend to sink to the floor level where they can spread over a large area.
  • No storage of flammable chemicals in container sizes greater than 1 gallon will be permitted in labs unless: a) The flammable chemicals are stored in a flammable storage cabinet or b) The flammable chemicals are stored in an approved flammable safety can.

What do I do if the material spills?

  • Turn off all possible sources of ignition
  • Alert those in the immediate area
  • Vacate area and notify proper authority

Examples of Flammable Materials:

 

Chemical Flash Point Boiling Point NFPA Class
  ° F ° C ° F ° C  
Acetaldehyde -38 -39 69 21 IA
Dimethyl sulfide -36 -38 99 37 IA
Ethyl ether -49 -45 95 35 IA
Ethylene oxide -20 -29 55 13 IA
Pentane -57 -49 97 36 IA
Propane -157 -105 -44 -42 IA
Benzene 12 -11 176 80 IB
Carbon disulfide -22 -30 115 46 IB
Cyclohexane -4 -20 179 81 IB
Ethyl alcohol 55 13 173 78 IB
n-Hexane -7 -22 156 69 IB
Methyl alcohol 52 11 149 65 IB
Methyl ethyl ketone 16 -9 176 80 IB
Pyridine 68 20 239-241 116 IB
Tetrahydrofuran 6 -14 153 67 IB
Toluene 40 4 231 111 IB
Triethylamine 20 -7 193 89 IB
tert Butyl isocyanate 80 27 185-187 85-86 IC
Chlorobenzene 82 28 270 132 IC
Epichlorohydrin 88 31 239-243 115-117 IC
2-Nitropropane 75 24 248 120 IC
Xylene 81-90 27-32 280-291 138-144 IC
Acetic Acid, glacial 103 39 244 48 II
Bromobenzene 118 48 307-316 153-158 II
Formic Acid 156 69 213 101 II
Morpholine 100 38 263 128 II
Stoddard Solvent 100-140 38-60 300-400 150-200 II
Benzaldehyde 145 63 352 178 IIIA
Cyclohexanol 154 68 322 161 IIIA
Methacrylic Acid 170 77 316 158 IIIA
Nitrobenzene 190 88 412 211 IIIA
Tetrahydronaphthalene 160 71 406 208 IIIA
Benzyl Alcohol 213 101 401 205 IIIB
Caproic Acid 215 102 400 204 IIIB
Ethylene Glycol 232 111 388 198 IIIB
Phenyl Ether 239 115 498 258 IIIB
Stearic Acid 385 196 726 386 IIIB


 

Page last modified March 18, 2014