Readily Combustible Solids or Flammability of Solids (Burning Rate) – UN Test N.1 Testing
Our UK laboratory generates test data for materials that you are looking to transport. The Readily Combustible Solids or Flammability of Solids (Burning Rate) – UN Test N.1 is primarily conducted for the purposes of transportation classification.
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Frequently asked questions
What are your Standards & Schedule of Accreditation?
Recommendations on the Transport of Dangerous Goods, UN Manual of Test & Criteria – UN Test N.1
What is the Readily Combustible Solids or Flammability of Solids (Burning Rate) – UN Test N.1?
The Readily Combustible Solids or Flammability of Solids (Burning Rate) – UN Test N.1 is conducted to determine whether a solid material should be classified for transportation as a flammable, or readily combustible, substance of UN Class 4, Division 4.1. The same test technique is used for the classification of CLP as a Flammable Solid (H.228)
How does the Readily Combustible Solids or Flammability of Solids (Burning Rate) – UN Test N.1 work?
A powder train strip is formed using a triangular cross-sectioned mould onto a heat-resistant, non-porous plate. Using a butane flame, one end of the powder train the strip is ignited and an initial time taken to burn over a marked 200 mm length is recorded.
If the burning rate test time is equal to, or less than 120s, then further trials are conducted over fresh powder strips. The burning time and burning rate test over a length of 100 mm are measured.
What is Flammable or Combustible Solid Classification?
If the time taken is equal to or less than 45 s (2.2 mm.s-1) then the material is classified as a ‘Flammable or Combustible Solid, of UN Class 4, Division 4.1. During the 100 mm trials, a section of the material past the 100 mm mark is subjected to wetting and observations are made to whether the wetted zone, stops flame propagation for at least 4 minutes.
What are the Packaging Groups?
If the wetted zone fails to stop propagation, the material is designated to Packing Group II. If it succeeds in stopping propagation, a Packing Group III designation is given. The preliminary screening test method is identical to that detailed within CLP/GHS’ regulatory requirements and procedures and therefore, the test data as gathered and carried out by the preliminary screening test can be used for both applications.