Hazard Information
GHS FAQ
Hazard Statements, or H-statements, are part of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). H-statements provide standardized wording and pictograms to indicate the chemical hazards of a product, including the degree of chemical hazard.
Hazard Statements are assigned a unique numerical code, which can be used as a useful reference when translating labels and MSDS data sheets. Keep in mind that the codes are not a substitute for writing out the entire text of the H-statement.
H-Statements take the form Hnxx, where H stands for “hazard statement” or “H-statement”; n is substituted with 2 for physical hazards, 3 for health hazards, and 4 for environmental factors. xx is a sequential numbering scheme.
Unstable Explosive
Division 1.1
Division 1.2
Division 1.3
Division 1.4
Division 1.5
Division 1.6
Danger
Danger
Danger
Unstable Explosive
Explosion;
Mass explosion
hazard
Explosion; Severe Projection Hazard
Explosion; fire, blast or projection hazard
Fire or Projection Hazard
May explode in fire
Additional Information: An explosive substance is a solid or liquid material that, by chemical reactive, is in itself capable of producing gas at such a temperature and pressure and at such a speed as to cause damage to the surroundings. A pyrotechnic substance or mixture is designed to produce an effect by heat, light, sound, gas, or smoke as the result of non-detonative self-sustaining exothermic chemical reactions. Explosive articles contain one or more explosive substance or mixtures while a pyrotechnic articles contain one or more pyrotechnic substances or mixtures.
For additional MSDS GHS terms, view the GHS glossary.
Hazard
Category
Category 1
Category 2
Signal
Word
Danger
Warning
Extremely flammable gas
Flammable gas
Definition
Gases ignite when in mixture of
= 13% in air or flammable
range with air of >/=12% (regardless of the lower flammable limit).
Gases, other than those of Category 1, having a flammable range while mixed in air.
Hazard
Symbol
Transport Symbol
Hazard
Category
Category 1
Category 2
Signal
Word
Danger
Warning
Extremely flammable aerosol
Flammable aerosol
Definition
Extremely flammable
aerosols. NOTE: If a product
is NOT tested, classify it
in Category 1.
Flammable aerosols.
Hazard
Symbol
Transport Symbol
Category 1
Danger
May cause or intensify fire; oxidizer.
Hazard
Category
Compressed Gas
Liquified Gas
Dissolved Gas
Refrigerated Liquefied Gas
Signal
Word
Danger
Warning
Warning
Warning
Contains gas under pressure; may explode if heated.
Contains gas under pressure; may explode if heated.
Contains gas under pressure; may explode if heater.
Contains refrigerated gas; may cause cryogenic burns or injury.
Definition
Extremely flammable aerosols. NOTE: If a product is NOT
tested, classify it in Category 1.
Partially liquid at
temperatures > -50C. *high pressure liquefied gas:
critical temperature between
-50C and 65C; *low
pressure liquefied gas: a
gas with a critical
temperature >65C.
Dissolved in a liquid phase solvent.
Partially liquid because of its
low temperature.
Hazard
Symbol
Transport Symbol
Hazard
Category
Category 1
Category 2
Category 3
Category 4
Signal
Word
Danger
Danger
Warning
Warning
Extremely flammable liquid and vapor
Highly flammable liquid and
vapor
Flammable liquid and vapor
Combustible liquid.
Definition
Extremely flammable liquid and vapor – Flashpoint < 23C and initial boiling point = 35C.
Highly flammable liquid and
vapor – Flashpoint <23C and
initial boiling point >35C.
Flammable liquid and
vapor – Flashpoint
>/= 23C and = 60C.
Combustible liquid –
Flashpoint > 60C and = 93C
Hazard
Symbol
Transport Symbol
Category 1
Category 2
Danger
Warning
Flammable solid.
Flammable solid.
Type A
Type B
Type C
Type D
Type E
Type F
Type G
Danger
Danger
Danger
Danger
Warning
Warning
Heating may cause
an explosion
Heating may cause explosion or fire.
Heating may cause
a fire.
Heating may cause
a fire.
Heating may cause
a fire.
Heating may cause
a fire.
Category 1
Category 2
Danger
Warning
Self-heating;
may catch fire.
Self-heating in
large quantities;
may catch fire.
Category 1
Danger
Catches fire spontaneously if exposed to air.
Category 1
Danger
Catches fire spontaneously if exposed to air.
Flammable Gases
Hazard
Category
Category 1
Category 2
Category 3
Signal
Word
Danger
Danger
Warning
In contact with water releases flammable gases, which may ignite spontaneously.
In contact with water releases flammable gas.
In contact with water releases flammable gas.
Definition
If in contact with water
reacts slowly at ambient temperatures such that
the maximum rate of
evolution of flammable gas
is equal to or greater than
1 liter per kg of substance
per hour AND reacts
vigorously with waterat
ambient temperatures and demonstrate generally a
tendency for the gas produced
to ignite spontaneously, or
reacts readily with water at
ambient temperatures such
that the rate of evolution of flammable gas is equal to or greater than 10 liters per kg
of substance over any 1 min.
If in contact with water it
readily reacts with water
at ambient temperatures
such that the maximum rate
of evolution of flammable
gas is equal to or greater
than 20 liters per kilogram
of substance per hour.
Hazard
Symbol
Transport Symbol
Hazard
Category
Category 1
Category 2
Category 3
Signal
Word
Danger
Danger
Warning
May cause fire or explosion; strong oxidizer.
May intense
fire; oxidizer
May intense
fire; oxidizer
Definition
In the mixture, by mass, of substance (or mixture) and cellulose tested, exhibit a
mean pressure rise time
less than or equal to the
mean pressure rise time of
a 1:1 mixture, by mass, of
50% perchloric acid
and cellulose.
In the mixture, by mass, of substance (or mixture) and cellulose tested, exhibit a
mean pressure rise time
less than or equal to the
mean pressure rise time of
a 1:1 mixture, by mass, of
40% aqueous sodium
chlorate and cellulose.
In the mixture, by mass, of substance (or mixture) and cellulose tested, exhibit a
mean pressure rise time
less than or equal to the
mean pressure rise time of
a 1:1 mixture, by mass, of
65% aqueous nitric acid
and cellulose.
Hazard
Symbol
Transport Symbol
Hazard
Category
Category 1
Category 2
Category 3
Signal
Word
Danger
Danger
Warning
May cause fire or explosion; strong oxidizer.
May intense
fire; oxidizer
May intense
fire; oxidizer
Definition
The substance/solid, the 4:1
or 1:1 sample-to-cellulose
ratio, by mass tested,
exhibits a mean burning
time less than or equal to
the mean burning time of a
3:2 mixture, by mass, of potassium bromate
and cellulose.
The substance/solid, the 4:1
or 1:1 sample-to-cellulose
ratio, by mass tested,
exhibits a mean burning time
less than or equal to the
mean burning time of a
2:3 mixture, by mass, of potassium bromate
and cellulose.
The substance/solid, in the
4:1 or 1:1 sample-to-
cellulose ratio, by mass
tested, exhibits a mean
burning time less than or
equal to the mean burning
time of a 3:7 mixture, by
mass, of potassium
bromate and cellulose.
Hazard
Symbol
Transport Symbol
Hazard
Category
Type A
Type B
Type C
Type D
Type E
Type F
Type G
Signal
Word
Danger
Danger
Danger
Danger
Warning
Warning
N/A
Heating may cause an explosion.
Heating may cause fire of explosion.
Heating may cause a fire.
Heating may cause a fire.
Heating may cause a fire.
Heating may cause a fire.
N/A
Definition
Propagation of detonation.
Detonation in the package.
Deflagration in the package.
Rapid deflagration in the
package.
Effect of heating under confinement.
Explosive power.
Thermal explosion in the
package.
Hazard
Symbol
Transport Symbol
Hazard Category
Category 1
Signal Word
Warning
Extremely flammable gas
Hazard Symbol
Transport Symbol
