Fire & Emergency Guidelines
Precautions/NFPA Ratings
Fire risks of flammable and combustible liquid can be minimized by understanding the fire hazard presented by chemicals used in the laboratory. The National Fire Protection Association (NFPA) classifies most flammable and combustible chemicals according to the severity of the fire hazard with numbers 0 to 4 in order of increasing hazard: 0 will not burn; 1 must be preheated to burn; 2 ignites when moderately heated; 3 ignites at normal temperature; 4 extremely flammable. Apply the following precautions to minimize fire risks:
- Use properly labeled containers. Many labels list NFPA ratings. MSDSs should also be consulted.
- Use special care when handling flammable liquids with flash points near or below 38°C because these chemicals increase the flammability threat in a normal laboratory environment.
- Keep containers of flammable substances tightly closed at all times when not in use.
- Use flammable liquids in a fume hood. The hood provides ventilation to prevent buildup of ignitable vapor/air mixtures or inhalation of toxic vapors or gases.
- Avoid placing ignition sources (hot materials, flames or sparking equipment) in the general vicinity of these liquids. If possible replace open flames by electrical heating.
- Ground equipment likely to produce a static spark.
- The volatility and hazards of flammable liquids are increased by heating. Additional safety requirements are necessary when flammable and combustible liquids are heated to or above their flash points. These include proper ventilation, protection from ignition sources, and electrical area classifications. Consult EH&S for further assistance.
- Compressed or liquefied gases present special fire hazards. Refer to EH&S' Compressed Gas Guidelines.
Contact between incompatible chemicals presents a serious fire risk. Proper handling and storage procedures should be followed.
| Health | 0
No hazard |
1
Slight hazard; irritation or minor injury possible |
2
Dangerous; exposure is hazardous to health |
3
Extreme danger; serious injury likely from exposure |
4
Deadly; even slightest exposure can be life-threatening |
| Flammability | 0
Will not burn |
1
Flash point above 200°F; substance must be preheated |
2
Flash point below 200°F; moderately heated conditions may ignite substance |
3
Flash point below 100°F; flammable, volatile, or explosive; use extreme caution |
4
Flash point below 73°F; very flammable, volatile or explosive; use extreme caution |
| Reactivity | 0
Stable when exposed to heat, pressure or water |
1
Normally stable; may become unstable with elevated heat, pressure or water |
2
Unstable; violent chemical changes possible at normal conditions; potentially explosive with water |
3
Explosive; readily capable of detonation by strong initiating source, such as water, heat or shock |
4
May detonate; readily capable of detonation at normal temperature and pressure |
| Additional Marking | W
Reacts violently with water |
OXY
Strong oxidizing chemical |
Radioactive material |
other symbols may be used |
Storage Cabinets
Flammable and combustible liquids, including waste solvents in quantities greater than ten gallons, must be stored in approved flammable liquid storage cabinets. Cabinets must be placed where they will not obstruct egress.
Safety Cans
Safety cans are constructed of stainless steel, or tin and come equipped with a flame arrestor and spring-loaded cap on both the filling and pouring spouts. The double-perforated metal surface of the flame-arrestor screen prevents flames from entering the container. Safety cans are available for both dispensing products and collecting waste. Safety cans shall not be modified.
Refrigerator Storage
Commercially-available, domestic refrigerators contain built-in ignition sources and shall not be used to store flammable liquids or explosive chemicals. Light bulbs, switches, temperature controls, standard plugs, motor-starting relays, thermal-overload devices, and heater strips (for frost control) are all ignition sources. Refer to EH&S' electrical safety information.
Anyone who needs a refrigerator to store flammable liquids or explosives should use refrigerators specifically designed and approved for such use. Refrigerators and freezers that have either been specifically designed or modified to store flammable and/or combustible liquids safely shall be labeled as such. Labels are available from EH&S.
Corridors and Exits
All laboratory buildings are provided with egress systems (corridors, stairs, doors) to meet the requirements of the Uniform Building Code and NFPA Life Safety Code. This egress system provides building occupants with a safe way out of the building, as well as the Fire Department with a way into buildings, in the event of emergencies. To maintain the integrity of the egress system, the requirements below shall be observed:
- Corridors must always remain free of obstructions or impediments, and combustible or flammable materials cannot be stored here.
- Exit doors, including the floor area on both sides of the exit door, must be kept clear and accessible at all times.
- Corridor doors must never be blocked or wedged open.
- All penetrations made to walls and floors to accommodate piping, electrical conduit, wiring, or ducts must be properly sealed with approved fire-stopping materials.