The National Fire Protection Association (NFPA) system
uses a diamond-shaped diagram of symbols and numbers to indicate the degree of
hazard associated with a particular chemical or material.
These diamond shaped symbols are placed on containers of chemicals or
materials to identify the degree of hazard associated with the chemical or
material. The diagram identifies
three color-coded categories of hazard for each material.
Each category is divided in levels of hazard potential with increasing
numbers indicating increasing hazards. The
abbreviated degrees of hazard in each of these categories are given as follows:
HEALTH - The degree of health hazard of a chemical or material
is based on the form or condition of the material, as well as its inherent
properties. The degree of health
hazard of a material should indicate the degree of personal protective equipment
required for working safety with the material.
�
1
is for slightly hazardous (toxic) material which requires only minimal
protection (for example, safety glasses and gloves) in addition to normal work
clothing to work with safely.
�
2
is for moderately toxic or a hazardous or moderately toxic material which
requires additional PPE or equipment (e.g. chemical goggles, lab/work smock,
local ventilation) in addition to that required for less toxic material. Consult
the MSDS for specific health hazard and proper PPE to use with this material.
�
3
or 4 is for highly to extremely toxic (deadly) materials (and any carcinogen,
mutagen, or teratogen). These
materials will require specialized equipment (e.g. respirator or exhaust hood,
full face shield, rubber apron, specialized glove, handling tongs, etc) beyond
that required for moderately toxic material.
You must consult the MSDS and/or other safety information to determine
the hazard (acute or chronic) and the proper PPE and engineering controls to
safely use this material.
FLAMMABILITY or FIRE HAZARD - The flammability or fire
hazards deal with the degree of susceptibility of the material to ignite and
burn. The form or condition of the
materials, as well as their properties, affects the extent of the hazard.
Many hazardous materials such as acetone and gasoline, have a flash point
(ignition temperature) far below freezing and will readily ignite with a spark
if the vapor concentration is sufficient.
�
1
is for materials with a flash point above 200�F.
�
2
is for materials with a flash point below 200�F but above 100�F.
�
3
is for materials with a flash point below 100�F but above 73�F.
�
4
is for materials with a flash point below 73�F.
REACTIVITY - The reactivity hazards deal with the potential of a
material or chemical to release energy. Some
materials are capable of rapid energy release without any catalyst, while others
can undergo violent eruptive or explosive reactions if they come in contact with
water or other materials. Generally
this rating is used to indicate the potential to react if the material is
heated, jarred, or shocked.
�
1
indicates a material that may be reactive if heated and one that reacts with
water.
�
2
indicates a material that may react violently without detonation.
�
3
indicates a material that may detonate or explode if subjected to a strong
initiating force or heating under confinement.
�
4
indicates a material that readily detonates or explodes.
SPECIFIC HAZARD - An open space at the bottom of the NFPA diagram can be used to indicate
additional information about the chemical or material.
This information may include the chemical or material's radioactivity,
proper fire extinguishing agent, skin hazard, its use in pressurized containers,
protective equipment required, or unusual reactivity with water.
�
OX
or OXY indicates a material that is an oxidizer.
�
W
or W indicates a material that is water reactive.
�
ALK
indicates a material that is alkali.
�
COR
indicates a material that is corrosive.
�
RAD
indicates a material that is radioactive.
All
containers that hold carcinogens, reproductive hazards or acutely toxic
chemicals must be properly labeled concerning the health hazard posed by the
chemical. Most containers will have
the chemicals hazard clearly displayed on the label. However older chemicals and containers of solutions that are
mixed in the lab must be properly labeled by the laboratory worker.
The laboratory worker may write the hazard class (e.g. carcinogen, etc.)
on the container or use labels available from their Supervisor or Chemical
Hygiene Officer.