Bicycle South Australia has backed a push to reconsider mandatory helmet laws (MHLs) in an effort to bolster stagnated cycling participation rates.

It was prompted by a position paper from national cycling group Bicycle Network, which claimed Australia's stance on helmets was "out of step" with the rest of the world.

The 50,000-member organisation conducted a survey on the issue last year and found almost 60 per cent of cyclists believed they should be able to choose if they wear a helmet.

It has now called for a five-year trial to allow cyclists older than 17 to choose whether they use a helmet while riding on footpaths or off-road cycle paths, as they can in the Northern Territory.

Mandatory helmet laws were introduced across Australia in the early 1990s.

While there has been a 46.5 per cent reduction in cyclist deaths — 88 in 1982-89 compared to 47 in 1993-2000 — Bicycle Network argued this corresponded with a 35.3 per cent fall in road fatalities during the same period.

"Other factors and road safety interventions also clearly contributed to the corresponding fall in total road deaths," the organisation said in its position paper, adding that there had been "no meaningful reduction in fatalities over the past 20 years".

It also said cyclist numbers in Australia fell from 1986 to 1996 and had remained stagnant, pointing out that every other country, except New Zealand, had relaxed their helmet laws so they applied only in certain circumstances.

Bike SA does not propose making helmets optional on busy roads and highways. ( ABC News: Malcolm Sutton )

'Helmet laws reducing cyclist numbers'

Bike SA chief executive Christian Haag told ABC Radio Adelaide's Breakfast program that Australia experienced a 30 per cent reduction in cycling participation rates after helmet laws were introduced.

"The most interesting figure from the BN survey is that there are 30 per cent of respondents who articulated they would ride their bicycle if mandatory helmet laws were removed," he said.

"So we have this cohort of the community who are behaviourally very sensitive to the impost of having to wear a helmet."

He backed the proposal for a five-year trial and suggested suburban roads should also be considered for the helmet-free zone.

Shane Rattenbury earlier this year backed a push to reconsider MHLs in certain circumstances. ( ABC News: Jake Evans )

But Transport Minister Stephan Knoll ruled out a change to South Australia's laws, calling the idea "a little incongruous" with the discussions and information he had received in support of encouraging more cyclists on the road.

"More than someone having helmet hair, I would have thought making people feel safe, that they can get to and from work, or where they go to more safely and while feeling safer, is a much more important thing we can do to improve cycling rates in SA," he said.

The BN position paper pointed to cities like Copenhagen and Amsterdam that had no MHLs and where cyclists constituted half of all commuters.

It also pointed to Seville where participation rates had "multiplied eleven-fold in a few short years thanks to steady investment and the construction of 75 miles of separated and protected cycling networks".

The ACT's Road Safety Minister, Shane Rattenbury, earlier this year also backed a push to reconsider helmet laws in certain circumstances.

Former trauma doctor criticises argument

But Bill Griggs, the former director of trauma services at the Royal Adelaide Hospital, said it was flawed to suggest that removing cyclists from cars was the best way to protect people rather than wearing personal equipment like helmets.

"That's like saying we should make seat belts in cars not compulsory because we should design cars that don't crash," he said.

"But if you take a person who's riding a bike and they fall off, for whatever reason, the most common serious injury we've seen in the hospital in my 40-odd years has been brain injuries."

Dr Griggs added that referring to Copenhagen or Amsterdam was also flawed because those cities enjoyed a "completely different approach to cycling".

"Over many years, they have built up infrastructure and their cycling paths are completely separated from the road," he said.

"Also, the culture is, among the many people who use the bikes for commuting, they are not riding much faster than pedestrians and are often mixed with pedestrians as well."

Copenhagen is another major city that does not have mandatory helmet laws. ( Flickr: Mikael Colville-Anderson )

Mr Haag said there was no doubt that wearing a helmet greatly reduced the likelihood of head trauma in an accident, but "our fatality and casualty rates and injury rates are not diminishing".

"Bike helmets will always play a crucial part in rider safety — if you hit the deck and hit your head, you're far better off with a helmet on," he said.

"[But] it's worthwhile asking the question, for those short trips in local suburban streets, which are obviously very quiet in terms of numbers of vehicles, but also those off-road shared paths:

"Is there an opportunity to look at increasing participation and providing flexibility for people's choices in those safe environments removed from motor vehicles?"

He said Bike SA would begin a survey in the next two weeks and hoped to have results by the end of November or early December.

"And I think then the process is to look at various policies and cycling network policy."