Dangerous goods testing, Test N.1 - Burning rate

Purpose

Dangerous goods are items or substances that can imply a risk for health, safety, property, or the environment. Some items, which may not be harmful by itself, may become a risk when combined with other substances.

Most regulations concerning dangerous goods, such as national regulations, the IMDG Code, IATA etc. are based on the UN Recommendations on the Transport of Dangerous Goods Model Regulations. The guidance document is developed by the United Nations to uniform national and international regulations. 

Dangerous goods are divided into nine different classes, grouped by their physical and chemical properties. Through testing a packaging group is assigned, in accordance with the degree of danger they present. In Division 4.1: 

^{CLASS       SUBSTANCE}
1.          Explosive substances and articles
2.          Gases
3.          Flammable liquids
4.1        Flammable solids
4.2        Substances liable to spontaneous combustion
4.3        Substances which, in contact with water, emit flammable gases
5.1        Oxidizing substances
5.2        Organic peroxides
6.1        Toxic substances 
6.2        Infectious substances
7.          Radioactive materials
8.          Corrosive substances
9.          Miscellaneous dangerous substances and articles

Testing is performed according to the UN manual of Tests and Criteria - Section 33: Division 4.1 Test N.1: Test method for flammable solids. The test generates data which can be used to classify dangerous goods and as a basis for risk analysis and research.

Method

Testing is performed by applying a burner to a 250 mm unbroken strip, or powder train, of the material which rests on an impervious surface. Ignition and flame propagation is observed. Initial testing is performed according to 33.2.4.3.1 Preliminary screening test, if the material propagates combustion in a given time frame the Burning rate test, according to 33.2.4.3.2, shall be carried out. In the Burning rate test the burning time is measured and depending on how fast the flame front propagates the product is assigned a suitable packing group.

The product can be classified as "Not a flammable solid", "Flammable solid - Packing group II/Cat. 1" or "Flammable solid-  Packing group III/Cat. 2".

Deliveries

The result is summarized by RISE in a written report. The report is delivered in English.