Determining whether a material meets the definition of a readily combustible solid under Transportation of Dangerous Goods (TDG) regulations is an important step in safe handling and regulatory compliance. LCS Laboratory Inc. performs a practical screening test based on the United Nations Manual of Tests and Criteria (2019, Rev. 7, Section 33.2.4) to evaluate whether a material can ignite and sustain flame propagation.
How the Screening Test Works
The method follows the UN Test N.1 procedure, which measures whether a material can ignite and maintain flame spread over a defined distance. If the sample does not ignite or does not propagate a flame, it is considered non‑flammable for the purposes of this classification, and no additional testing is required.
Why the Screening Test Can Save Clients Money
Full UN Test N.1 testing can be time‑consuming and costly, especially when multiple replicates and confirmatory trials are required. The screening test provides an economical first step. If the material clearly fails to ignite or propagate a flame during screening, the client can avoid the expense of full-scale testing. This early determination often prevents unnecessary laboratory work, reduces project timelines, and helps manufacturers and distributors confirm TDG exemptions before committing to more complex regulatory evaluations.
Typical Materials With High or Low Burning Rates
Different materials behave very differently in the UN burning‑rate test:
Materials that often show dangerously high burning rates
- Magnesium and magnesium‑based alloys
- Metal powders with reactive surfaces
- Paper or cardboard containing wax, oils, or other combustible coatings
- Fine organic powders with high surface area
These materials can ignite easily and sustain rapid flame propagation, making them more likely to be classified as readily combustible.
Materials that typically show very low burning rates
- Sawdust
- Coal dust
- Charcoal fines
- Many polymer powders and granules
These materials often smolder rather than burn with an open flame, and in many cases do not meet the criteria for a readily combustible solid.
Benefits of Using the Screening Test
- Cost‑efficient compliance – Early confirmation of non‑flammability helps avoid unnecessary full‑scale testing.
- Reduced regulatory burden – Non‑flammable materials face fewer TDG requirements for transport, storage, and labeling.
- Clear, defensible results – The method follows internationally recognized UN criteria, providing documentation suitable for audits and regulatory submissions.
- Faster project timelines – Rapid screening helps manufacturers and distributors move products through the compliance process without delays.
Suitable Materials for Screening
The test is commonly used for:
- Industrial powders and granules
- Bulk chemicals and raw materials
- Process residues
- Consumer products requiring TDG classification
Professional Testing Services
LCS Laboratory Inc. provides accurate, defensible testing aligned with UN and TDG requirements. To discuss your material or schedule a screening test, contact our laboratory team. ©
