Transportation Testing

U. S. Department of Transportation (DOT) and United Nations (UN) transportation testing.

United Nations, UN, (international) and US Department of Transportation, DOT, (domestic) have developed a scheme for the classification of certain types of dangerous goods and give descriptions of the tests and procedures to arrive at a classification for transport. Dangerous goods are chemical substances or articles containing chemical substances, which can pose threat to public safety or to the environment during transport through chemical, physical, or nuclear properties if not properly identified or packaged. If they are accidentally released undesirable outcomes such as fires and explosions can occur. The purpose of the various tests is to provide adequate protection against the risks to life and property inherent in the transportation of hazardous materials in commerce.

How We Can Help
Chilworth has the facilities and expertise to conduct the various UN and DOT tests. In addition, Chilworth has the familiarity with the regulations and can advise the clients on the classification.

Capabilities

Screening Procedures (CHETAH, DSC, ARC, Dewar)

Class 1 – Explosives, Test series 1, 2 and 3

  • UN Gap test (to measure the ability of a substance under confinement to propagate detonation)
  • Koenen test (to determine the sensitiveness of a substance to the effect of intense heat under high confinement)
  • Time Pressure test (to determine the effects of igniting a substance under confinement)
  • BAM Fallhammer test (to measure the sensitiveness to drop weight impact and to determine if the substance is too dangerous to transport in the form tested)
  • BAM Friction test (to measure the sensitiveness to friction stimuli and to determine if the substance is too dangerous to transport in the form tested)
  • Thermal Stability test (to measure the stability of substance when subjected to elevated thermal conditions to determine if the substance is too dangerous for transport)
  • Small Scale Burning test (to determine the response of a substance to fire)

Class 4 and Class 5 – Self Reactive Substances (Division 4.1) and Organic Peroxides (Division 5.2), Test series H

  • Adiabatic Storage test (to determine the SADT, self accelerating decomposition temperature)

Class 4 – Readily Combustible Solids (Division 4.1), Test N.1

  • Burning Rate Test (to determine the ability of a substance to propagate combustion)

Class 4 – Substances Liable to Spontaneous Combustion (Division 4.2), Tests N.2, N.3 and N.4

  • Pyrophoricity test (to determine the pyrophoricity of a substance)
  • Self-Heating test (to determine the ability of a substance to undergo oxidative self-heating)

Class 4 – Substances which in Contact with Water Emit Flammable Gases (Division 4.3), Test N.5

  • Filter paper and Conical tests (to determine whether reaction with water produces dangerous gases which may be flammable)

Class 5 – Oxidizing Substances (Division 5.1), Tests O.1 and O.2

  • Burning time test (to determine the potential to increase the burning rate or intensity)

Please contact Chilworth for any other UN and DOT tests not shown above.

 

Burning Rate Test – DOT/UN Division 4.1
The Burning Rate or Fire Train Test is used to classify materials as “flammable solids” in accordance with U.S. Department of Transportation (DOT) and United Nations (UN) requirements. Chilworth Global performs the Burning Rate Test in accordance with the method described in 49 CFR 173 Appendix E and UN Recommendations on the Transport of Dangerous Goods. The test involves igniting a 250 mm x 20 mm x 10 mm powder train using a suitable ignition source and measuring the burning rate (time).

Pyrophoric Solids Test – DOT/UN Division 4.2
The Pyrophoric Solids Test is used to classify solids materials as “spontaneously combustible” in accordance with U.S. Department of Transportation (DOT) and United Nations (UN) requirements. Chilworth Global performs the Pyrophoric Solids Test in accordance with the method described in 49 CFR 173 Appendix E and UN Recommendations on the Transport of Dangerous Goods. The test involves pouring a powder sample from a height of one meter onto a non-flammable surface and observing whether the sample ignites during its descent or after settling.

Self-Heating Substances Test – DOT/UN Division 4.2
The Self-Heating Substances Test is the second of two tests used to classify materials as “spontaneously combustible” in accordance with U.S. Department of Transportation (DOT) and United Nations (UN) requirements. Chilworth Global performs the Self-Heating Substances Test in accordance with the method described in 49 CFR 173 Appendix E and UN Recommendations on the Transport of Dangerous Goods.

The Self-Heating Substances Test involves placing a powder sample in a 100 mm x 100 mm x 100 mm stainless steel cubic mesh basket and placing the basket in an oven where it is exposed to a constant temperature of 140 °C for 24 hours. If necessary, a second trial is performed using a 25 mm x 25 mm x 25 mm mesh basket. The sample and oven temperatures are continuously monitored at several locations for the duration of the test.

Dangerous When Wet Test – DOT/UN Division 4.3
The Dangerous When Wet Test is used to identify materials that — upon contact with water or moisture — are liable to become spontaneously flammable or evolve a flammable or toxic gas, as per U.S. Department of Transportation (DOT) and United Nations (UN) requirements. Chilworth Global performs the Dangerous When Wet Test in accordance with the method described in 49 CFR 173 Appendix E and UN Recommendations on the Transport of Dangerous Goods.

The Dangerous When Wet Test is comprised of four (4) parts, each of which involves exposing a small amount of solid sample to a limited amount of water. The samples are observed to determine whether gas is evolved and whether such gas is flammable. The volume of gas evolved is measured to determine the gas evolution rate.

Solid Oxidizing Substances Test – DOT/UN Division 5.1
The Solid Oxidizing Substances Test is used to classify materials as such in accordance with U.S. Department of Transportation (DOT) and United Nations (UN) requirements. Chilworth Global performs the Solid Oxidizing Substances Test in accordance with the method described in 49 CFR 173 Appendix F and UN Recommendations on the Transport of Dangerous Goods. The test involves mixing powder samples with sawdust in various proportions and observing the combustion characteristics when a conical pile of the sample/sawdust mixture is ignited by a hot loop ignition source.

Oxidizing Liquids Test – UN/DOT Division 5.1
The Oxidizing Liquids Test is used to classify materials in accordance with U.S. Department of Transportation (DOT) and United Nations (UN) requirements. Chilworth Global performs the Oxidizing Liquids Test in accordance with the method described in 49 CFR 173 Appendix F and the UN Recommendations on the Transport of Dangerous Goods using the Time/Pressure Test Apparatus.

The test involves mixing a 2.5 gram sample of the suspected liquid oxidizer with an equivalent sample of dried fibrous cellulose. The mixture is then loaded into the test cell and ignited using a fuse wire. A pressure transducer fitted to the test cell is used to measure the maximum deflagration pressure and maximum rate of pressure rise. The results for the sample and mixture are then compared to results for testing of mixtures of cellulose and known oxidizers to determine the classification and packing group.