We have several decades of combined research experience focused on child injury prevention. We enjoy doing this work as a way to affect real change and improve the lives of children and their families. We have had the privilege of joining a local, national and international family, each doing our bit for the collective whole. It has been immensely gratifying to see some real impacts from our collective efforts.

We have, however, become increasingly concerned that some of our efforts to keep children safe may be doing unintended harm – particularly as it relates to children’s play. We have had children’s best interests at heart, but our exclusive focus on injury prevention has been akin to only paying attention to whether we’re getting enough exercise, but not what kind of food we’re eating.

A child has many needs – safety being a very crucial one among many. But by only thinking about safety, we can lose sight of how we may inadvertently cause serious harms in other ways. Here at the BC Injury Research and Prevention Unit, we have written peer-reviewed research articles about this before – you can access them for free here: http://www.mdpi.com/1660-4601/9/9/3134 and http://injuryprevention.bmj.com/content/early/2014/12/22/injuryprev-2014-041241.full

Recently, the ASTM Committee on Sports Equipment, Playing Surfaces, and Facilities has been struggling with the decision to lower thresholds for Impact Attenuation Materials. Essentially, they want to require that surfaces under playground structures be more absorbent in order to reduce the likelihood of head injury. At first blush, this may seem like a great idea. Who wouldn’t want their child to avoid head injuries??! Not as evident are the ramifications, both immediate and long term, of a decision like this. While playground safety standards are not policies and are developed by a voluntary organization, they are typically applied as policy. This is because of liability concerns. If anything goes wrong, the playground provider wants to be able to support the fact that their playground met the safety standards as a measure of due diligence.

So what this means is that every time there is a playground standard change, schools, daycare centres, recreation facilities and so on across the country have to rip out equipment, surfacing, etc., to comply with new standards. There are several issues with this:

  1. Head injuries on the playground are extremely rare and there is no evidence that they are increasing on playgrounds. For example, studies that have looked at injuries across entire school districts in Canada and New Zealand have not documented even one head injury on the playground. In fact, your child is more likely to get injured doing sports than on the playground.
  2. The head injury criterion (HIC) is measured by dropping a head form straight down, but children do not fall that way. The most common injuries on the playground are arm fractures because children try to break their falls. Australian data show that introducing stricter playground safety standards in 1996 had no impact on head injury rates.
  3. Ripping out and replacing surfacing is a very expensive proposition, especially if you consider the sheer number of playgrounds across the US that will be affected. The resources have to come from somewhere, which means they won’t go to supporting other worthy and necessary activities. Also, a change in the ASTM standard is likely to have knock-on effects for standards in other countries, ultimately representing a huge worldwide shift in spending. A previous cost-benefit analysis found that it represented a large investment for very little return.
  4. Kids want and need to take risks and experience uncertainty. So reducing risks has several major ramifications:

(a) Taking risks is part of how they learn about the world, the consequences of actions, and how to keep themselves safe in different circumstances. I’d much rather my children learn that wet surfaces are slippery while playing, than when they’re driving their first car.

(b) Evidence suggests that kids take more risks when things are made safer – they’ll climb higher and fall harder.

(c) If they’re not getting the chance to take risks in playgrounds (where it’s relatively safe), they’re going to look for them elsewhere, through means that could be far more dangerous or destructive.

(d) Or they could disengage altogether, turning to screens, and other forms of sedentary entertainment. We are aware of the major concerns about children’s lack of physical activity and increasing rates of obesity.

  1. We’re already doing a miserable job of providing stimulating play opportunities for children. Making safety standards more stringent will just make it even harder. Lots of research has documented the effect of playground design on children’s development and well-being. We know how to design optimal play spaces for children and yet the vast majority of play spaces have uninspiring equipment with very little play value.

The members of the ASTM committee have a very difficult task ahead of them. It is one we also struggle with regularly through the course of our work. It is no easy feat to figure out the optimal balance between risk and safety. But we think it is possible to keep safety at top of mind, while still being sensitive to other aspects of children’s health, well-being and development. In this case, we believe that changing the standards will not reflect the best decision for children. Hence we would urge the committee to put the proposal on hold, and to engage in a wider debate about how standards can help us get the balance right.

We would also encourage you to read a posting by Professor David Ball for thoughtful and thorough consideration of arguments on this issue.

Dr. Mariana Brussoni 1
Dr. Alison Macperhson 2
Dr. Ian Pike 3


  1. Assistant Professor, Department of Pediatrics, School of Population and Public Health, University of British Columbia; Academic Scientist, BC Injury Research & Prevention Unit; Scientist, Child & Family research Institute; Director, BC Children’s Hospital Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP)
  2. Associate Professor, School of Kinesiology & Health Science, York University; CIHR Canada Research Chair in Reproductive, Child and Youth Health; Adjunct Scientist, Institute for Clinical Evaluative Sciences.
  3. Associate Professor, Department of Pediatrics; Director, BC Injury Research & Prevention Unit; Associate Scientist, Child & Family research Institute; Network Researcher, Auto 21; Co-Executive Director, Preventable