Substances not accepted for carriage
Substances of Class 3 which are liable to form peroxides easily (as happens with ethers or with certain
heterocyclic oxygenated substances) shall not be accepted for carriage if their peroxide content,
calculated as hydrogen peroxide (H2O2), exceeds 0.3%. The peroxide content shall be determined as
indicated in 188.8.131.52.
Chemically unstable substances of Class 3 shall not be accepted for carriage unless the necessary
precautions have been taken to prevent the possibility of a dangerous decomposition or
polymerization under normal conditions of carriage. For the precautions necessary to prevent
polymerization, see special provision 386 of Chapter 3.3. To this end particular care shall be taken to
ensure that receptacles and tanks do not contain any substances liable to promote these reactions.
Liquid desensitized explosives other than those listed in Table A of Chapter 3.2 shall not be accepted
for carriage as substances of Class 3.
List of collective entries
List of collective entries
Class 4.1 Flammable solids, self-reactive substances, polymerizing substances and solid desensitized explosives
The heading of Class 4.1 covers flammable substances and articles, desensitized explosives which are
solids according to subparagraph (a) of the definition "solid" in 1.2.1, self-reactive liquids or solids
and polymerizing substances..
The following are assigned to Class 4.1:
- readily flammable solid substances and articles (see paragraphs 184.108.40.206.3 to 220.127.116.11.8);
- self-reactive solids or liquids (see paragraphs 18.104.22.168.9 to 22.214.171.124.17);
- solid desensitized explosives (see 126.96.36.199.18);
- substances related to self-reactive substances (see 188.8.131.52.19);
- polymerizing substances (see 184.108.40.206.20 and 220.127.116.11.21).
The substances and articles of Class 4.1 are subdivided as follows:
F Flammable solids, without subsidiary risk:
F2 Organic, molten;
FO Flammable solids, oxidizing;
FT Flammable solids, toxic:
FT1 Organic, toxic;
FT2 Inorganic, toxic;
FC Flammable solids, corrosive:
FC1 Organic, corrosive;
FC2 Inorganic, corrosive;
D Solid desensitized explosives without subsidiary risk;
DT Solid desensitized explosives, toxic;
SR Self-reactive substances:
SR1 Not requiring temperature control;
SR2 Requiring temperature control.
PM Polymerizing substances
PM1 Not requiring temperature control;
PM2 Requiring temperature control.
Flammable solids Definition and properties
Flammable solids are readily combustible solids and solids which may cause fire through friction.
Readily combustible solids are powdered, granular, or pasty substances which are dangerous if they
can be easily ignited by brief contact with an ignition source, such as a burning match, and if the
flame spreads rapidly. The danger may come not only from the fire but also from toxic combustion
products. Metal powders are especially dangerous because of the difficulty of extinguishing a fire
since normal extinguishing agents such as carbon dioxide or water can increase the hazard.
Substances and articles classified as flammable solids of Class 4.1 are listed in Table A of Chapter
3.2. The assignment of organic substances and articles not mentioned by name in Table A of
Chapter 3.2 to the relevant entry of sub-section 18.104.22.168 in accordance with the provisions of Chapter
2.1 can be based on experience or on the results of the test procedures in accordance with Part III, subsection
33.2.1 of the Manual of Tests and Criteria. The assignment of inorganic substances not
mentioned by name shall be based on the results of the test procedures in accordance with Part III,
sub-section 33.2.1 of the Manual of Tests and Criteria; experience shall also be taken into account
when it leads to a more stringent assignment.
When substances not mentioned by name are assigned to one of the entries listed in 22.214.171.124 on the
basis of the test procedures in accordance with the Manual of Tests and Criteria, Part III, sub-section
33.2.1, the following criteria apply:
(a) With the exception of metal powders or powders of metal alloys, powdery, granular or pasty
substances shall be classified as readily flammable substances of Class 4.1 if they can be easily
ignited by brief contact with an ignition source (e.g. a burning match), or if, in the event of
ignition, the flame spreads rapidly, the burning time is less than 45 seconds for a measured
distance of 100 mm or the rate of burning is greater than 2.2 mm/s;
(b) Metal powders or powders of metal alloys shall be assigned to Class 4.1 if they can be ignited
by a flame and the reaction spreads over the whole length of the sample in 10 minutes or less.
Solids which may cause fire through friction shall be classified in Class 4.1 by analogy with existing
entries (e.g. matches) or in accordance with any appropriate special provision.
On the basis of the test procedure in accordance with the Manual of Tests and Criteria, Part III,
Section 33.2.1 and the criteria set out in 126.96.36.199.4 and 188.8.131.52.5, it may also be determined whether
the nature of a substance mentioned by name is such that the substance is not subject to the provisions
for this Class.
If substances of Class 4.1, as a result of admixtures, come into different categories of risk from those
to which the substances mentioned by name in Table A of Chapter 3.2 belong, these mixtures shall be
assigned to the entries to which they belong on the basis of their actual degree of danger.
NOTE: For the classification of solutions and mixtures (such as preparations and wastes), see also