BEFORE helmets are sold, samples are randomly selected for tests that include dealing them severe blows at high speeds.
The batch testing process ensures helmets will offer riders a reasonable measure of protection, said TUV SUD PSB, a product testing, inspection and certification firm formerly called PSB Corporation.
About 4 per cent of the batches tested fail because of "poor design and the unsuitability of the material used", said a company spokesman.
Checks are run on the helmet's construction, the uniformity of the shell thickness, the lining material used in the protective padding, and the chin strap's fastening device. Helmets also undergo shock absorption and penetration tests. Those that meet the requirements are affixed with a PSB test mark.
Still, a helmet's ability to protect the rider can be affected if it is not worn properly, if it does not fit the wearer's head properly, or if the chin strap is not used.
And in severe accidents, it "might not fully prevent injury or death", said the spokesman. Its protective ability can also be affected if the wearer modifies it by, say, changing the strap.
Wear and tear also take their toll over time, said Mr Tony Yeo, the general secretary of the Singapore Motor Cycle Trade Association. "I see a lot of helmets that even scrapyards don't want, but riders still wear."
This article was first published in The Straits Times on Nov 24, 2008.
