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The butane in this cigarette lighter is considered to be a liquefied gas under the GHS, and not a liquid. Cigarette lighters containing flammable gases are transported under UN class 2.1, UN number 1057.

http://www.ca5.uscourts.gov/opinions%5Cpub%5C93/93-02564.CV0.wpd.pdf

Flammable gas

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Flammability is measured by the ISO 10156:1996 test method.[1]

Flammable aerosols

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The GHS uses the general definition of an "aerosol", that is an aerosol spray, but also includes similar dispensing systems which produce foams rather than true aerosols. An aerosol dispensing system typically contains a propellant gas under pressure and a liquid phase: some aerosols also contain small solid particles in suspension in the liquid. An aerosol is potentially flammable if it contains a flammable gas, a flammable liquid or a flammable solid.[2] However if the proportion of flammable components is less than 1% and the heat of combustion is less than 20 kJ/g, the aerosol is not classified as flammable (and may be transported under UN transport class 2.2).[3][4]

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The heat of combustion may either be taken from literature values of the standard enthalpy change of combustion (multiplied by a factor of 0.95 to take account of incomplete combustion) or measured experimentally by standard methods such as ASTM D240,ISO/FDIS 13943:1999 or NFPA 30B.[5] The Spray ignition test,[6] the Enclosed space ignition test[7] and the Aerosol foam flammability test[8] are described in the UN Manual of Tests and Criteria.

Flammable liquids

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Under the GHS, a flammable liquid is any liquid with a flash point of no more than 93 ºC.[9]

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Flammable solids

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The GHS[10] and the UN Manual of Tests and Criteria[11] both use the phrases "flammable solid" and "readily combustible solid" in recognition of the fact that many solids with burn without a flame (but while giving off heat and decomposing). The distinction is not important for GHS classification, which is based on the UN Model Regulations.[12]

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The Burning rate test is described in the UN Manual of Tests and Criteria.[13]

Self-reactive substances and mixtures

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The category of "self-reactive substances or mixtures" is wide, and runs from some extremely shock sensitive explosives to other substances which pose no significant risk in their use of transport. The GHS definition is based on the UN Recommendations for the Transport of Dangerous Goods: the following are not classified under this hazard group, even though they may have similar hazards:

  • Class 1 goods, that is "explosives" under the transport regulations;
  • Organic peroxides, although the categorization scheme for these substances is essentially the same as for other self-reactive substances except for the transport class;
  • Oxidizing agents.

After these three groups have been removed, the GHS defines "self-reacting substances and mixtures" as those remaining which

are thermally unstable liquid or solid substances or mixtures liable to undergo a strongly exothermic decomposition even without the the participation of oxygen (air).

Substances or mixtures for which the heat of decomposition is less than 300 J/g, or for which the self-accelerating decomposition temperature for a 50 kg package is higher than 75 ºC, do not need to be classified under this heading. The heading also includes a "type G", which are substances or mixtures which might otherwise meet the definition of "self-reactive", but which have no significant transport or handling risks in that respect.

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Pyrophoric liquids and solids

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Pyrophoric substances will catch fire spontaneously on contact with air. The GHS contains a single category, but distinguishes between liquids and solids because of the different transport hazards. Pyrophoric substances may be considered to be the extreme case of self-heating substances (see below).

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Self-heating substances and mixtures

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Self-heating susbtances and mixtures will gain temperature dangerously when exposed to air and without any external heat source. They may eventually catch fire, but only when large quantities are exposed to air and after a period of hours or days: this is the difference from substances classed as "pyrophoric" (see above). In general, the risk is higher with larger amounts of the substance or mixture and at higher ambient temperatures.

For transport purposes, the threshold level of self-heating is that of charcoal, which will eventually catch fire in air at 50 ºC if packed as a cube of 27 m3 volume (sides of 3 metres): substances which are more hazardous than charcoal must be labelled for transport. The practical tests are carried out on smaller quantities and at higher temperatures.

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Substances and mixtures which, in contact with water, emit flammable gases

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Organic peroxides

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Notes

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  1. ^ Part 2, section 2.2.42., GHS Rev.2
  2. ^ Part 2, section 2.3.2.1, GHS Rev.2
  3. ^ Part 2, section 2.3.4.1, GHS Rev.2
  4. ^ Part 3, section 3.3.1, special provision 63, UN Model Regulations Rev.15
  5. ^ Part 2, section 2.3.4.2, GHS Rev.2
  6. ^ Part III, section 31.4, UN Manual of Tests and Criteria Rev.4
  7. ^ Part III, section 31.5, UN Manual of Tests and Criteria Rev.4
  8. ^ Part III, section 31.6, UN Manual of Tests and Criteria Rev.4
  9. ^ Part 2, section 2.6.1, GHS Rev. 2
  10. ^ Part 2, section 2.7.1, GHS Rev.2
  11. ^ Part II, section 33.2, UN Manual of Tests and Criteria Rev.4
  12. ^ Part 2, section 2.4.2.2, UN Model Regulations Rev.15
  13. ^ Part III, section 33.2.1.4, UN Manual of Tests and Criteria Rev.4

References

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  • Globally Harmonized System of Classification and Labelling of Chemicals (Second revised ed.), New York and Geneva: United Nations, 2007, ISBN 978-92-1-116957-7, ST/SG/AC.10/30/Rev.2 ("GHS Rev.2")
  • "Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006", OJCE (L353): 1–1355, 31.12.2008 {{citation}}: Check date values in: |date= (help) (the "CLP Regulation")
  • UN Recommendations on the Transport of Dangerous Goods. Model Regulations (Fifteenth ed.), New York and Geneva: United Nations, 2007 ("UN Model Regulations Rev.15")
  • UN Recommendations on the Transport of Dangerous Goods. Manual of Tests and Criteria (Fourth revised ed.), New York and Geneva: United Nations, 2002 ("UN Manual of Tests and Criteria Rev.4")