in the three subclasses referred to previously, starting with Class
Each schedule includes the substance's name, UN number,
Added information is provided under the standard headings of
properties, observations, packing, stowage, and segregation (as is
the case with the other classes).
Liquids in this class are also assigned to a packaging group which is
determined by the degree of danger these substances present.
Packaging Group I includes liquids presenting great danger, Group II
represents medium danger, and Group III means minor danger.
similar system of assigning dangerous goods to one of three packaging
groups is used in other classes of the IMDG code with the exception
of Classes 1*, 2, and 7.
Generally speaking, water is unsuitable in fighting a fire involving
inflammable liquids particularly for liquids which cannot mix with
Class 4 - Other Inflammables
This class is divided into three subclasses, each of which has very
The classes include some commonly known
products, many of which seem harmless enough but which can be very
dangerous unless properly packaged, handled, and transported.
Class 4.1 - Inflammable solids
Substances in this class are easily combustible and can be readily
ignited by external sources, such as sparks or flames.
individual schedules give the product's name, UN number, and chemical
formula. These schedules are often detailed since properties vary.
Some common products covered by this class are wetted explosives;
camphor; vegetable fibers such as cotton, jute, and hemp; hay and
straw; matches; rubber scrap; and sulphur.
Class 4.2 - Substances liable to spontaneous combustion
Substances in this class react to heat and are liable to ignite
spontaneously. Some are more likely to do so when wetted by water or
in contact with moist air. Some may also give off toxic
* Unless a specific provision to the contrary is made on individual
schedules for goods of Class 1, the packaging used should comply
with the requirements for the "medium danger" Packaging Group II.