The Hon. Carl Scully MP
Minister for Roads
Parliament House
Macquarie Street
SYDNEY 2000
Dear Mr Scully,
I am writing to request details of the knowledge that supports the following statements: "Bike helmets reduce brain damage" and "Cyclists must correctly wear an approved helmet. They help protect the brain in a crash."
These statements appear in a leaflet issued by the Cessnock City Council and the Maitland City Council, copy enclosed. Upon inquiry, I was told that it is based on information which the Roads and Traffic Authority supplied. The leaflet includes a telephone number for the RTA.
The statements run counter to theory of brain injury and the findings of experimental research on the effects of helmets as summarised in a 1994 report of the National Health and Medical Research Council, Football injuries of the head and neck. Quoting a little from it:
"The evidence that helmets reduce soft tissue injury is shown by studies examining the effectiveness of cycling helmets. … Whilst helmets may possibly reduce the incidence of scalp lacerations and other soft tissue injury, there is the risk that helmets may actually increase both the cerebral and non-cerebral injury rates. ... The addition of a helmet will increase both the size and mass of the head. This means that blows that would have been glancing become more solid and thus transmit increased rotational forces to the brain ... increase in diffuse brain injury."
Research by Corner et al, commissioned by the Federal Office of Road Safety, noted that helmets are tested for direct impacts only, but rotational acceleration of the head due to glancing blows is the main cause of brain injury. They showed that the added mass of a helmet increases rotational acceleration. They also said that the helmet shell should be very stiff with a low impact sliding reaction. Instead, the standard was amended to allow soft-shell helmets. Tests of impacts of helmets on asphalt have since shown that, unlike hard- shell helmets which slide, soft helmets grab the surface, producing high rotational accelerations.
Some more information on this matter is contained in submissions we made to the National Road Transport Commission, which I understand have been passed on to the RTA.
I submit that, to justify public authorities promulgating these statements and maintaining the law that compels cyclists to wear helmets, the assessments of the NHMRC and Corner et al would need to be convincingly refuted. In this connection, I point out that in 1995 I sought direct and through your predecessor the RTA's evaluation, upon which the compulsory helmet wearing law is based, of the evidence of the efficacy of helmets in protecting cyclists against injury. The RTA was unable to provide it.