The safety of trees

treesafetyTrees are an essential part of our ecosystem and for most people are also things of beauty. As a part of their natural life cycle they shed branches and ultimately fall down. Very rarely, this may result in harm to property or individuals. These uncommon events tend to receive a lot of publicity, possibly because of their rarity. On behalf of the National Tree Safety Group, John Watt and I reviewed the evidence on tree fall and injuries in the UK over the last decade in order to quantify the actual risk. The full paper can be found in the Journal of Risk Research (2013: 16(1-2): 261-269).

In terms of fatalities, the statistics point to around 5.4 cases per annum. Given the UK population during the study period (1998-2008) averaged 60 million, this indicates an annual individual risk of below 1 in 10 million. To put this in perspective, the lead regulator (HSE) has said that risks even as low as one in a million per year are extremely small when compared with the background risks of everyday life, and that most people are prepared to accept risks of this magnitude from all manner of hazards in exchange for the associated benefits.

Given the billion or so trees in Britain, the likelihood that the present fatality rate could be reduced below the current level is exceedingly low even were some draconian measures introduced (like cataloguing every tree and assessing it every year and after every storm). So we do not believe that any changes to the status quo are warranted. However, it is clear that different views exist. Some think that trees should be tightly managed and e.g. removed as soon as any disease is found. Others see trees as having a natural lifespan which includes some decay which in itself may be a legitimate part of the ecosystem.

Children and young people’s play

I first became involved professionally in children and young people’s play provision back in 1986 when working for the Scientific Branch of the Greater London Council. It happened by accident when some colleagues left and I was asked to absorb their activities into my own. I recall saying, ‘This is not going to take long – it’s a three month job.’ How wrong can you be?! Twenty five years later the topic rolls on and interest, if anything, is at an even higher pitch than ever.

Back in the 80s and 90s most of the questions on play were about safety – ‘How can I make my playground safe?’ – being the typical question, and many people believed the answer somehow lay in impact absorbing surfaces for playgrounds. The publication, in 1989, of ‘A holistic approach to accident and injury prevention in children’s playgrounds’ caused something of a stir since it contradicted the then conventional wisdom that rubber surfaces would prevent playground injuries.

Having finally persuaded at least some people that this was both the wrong question and the wrong solution, and having been joined by others who have independently come to the same realisation, the new question of the 2010s is along the lines of: ‘How can I make my playground into a good experiential opportunity for children and young people?’ At least the question is becoming more wholesome, although the safety conundrum lingers on.

In 2002 I received a contract from the Health and Safety Executive to review what was actually known about the safety of playgrounds in terms of accident statistics, and to interpret this in terms of general UK safety policy. The output of this was published by the HSE and can be found on its website at http://eprints.mdx.ac.uk/4990/1/crr02426.pdf from which it may be downloaded. At about this time, and hopefully assisted by the HSE report, the Play Safety Forum (PSF), to whom I am one of several advisers, published the first edition of its ground-breaking policy statement entitled ‘Managing risk in play provision – position statement’. In contrast to the messages of the previous decades which were largely about making playgrounds safe, the PSF’s position was starkly different. Children, it said, needed and wanted exposure to risk.

Two further publications by Play England and the government in 2008 took this a step further. These were ‘Managing risk in play provision – implementation guide,’ and ‘Design for play.’ These documents contained singularly important messages. The most important perhaps being:

  • risk assessment in the play sector should be replaced by risk benefit assessment (RBA)
  • that play spaces need natural features as well as manufactured equipment
  • that good play space is achieved not through a process of ‘design, install and forget,’ but rather one of ‘design, install, monitor and adjust’

However, although the PSF fully endorsed RBA in these publications and had, at the time, the support of the HSE, it appeared sometime later that HSE was less confident of this concept and some personnel appeared opposed. After a somewhat protracted deliberation between the PSF and the HSE during 2011-12, partly at the instigation of Lord Young who had said that this negotiation over risk-benefit should take place (http://www.number10.gov.uk/wp-content/uploads/402906_CommonSense_acc.pdf), the HSE in due course published on its website a high level statement on risk in play, and risk benefit assessment specifically, on 3 September 2012 (http://www.hse.gov.uk/entertainment/childrens-play-july-2012.pdf). The HSE statement includes the following paragraph:

“To help with controlling risks sensibly and proportionately, the play sector has produced the publication Managing Risk in Play Provision: Implementation Guide which provides guidance on managing the risks in play. The approach in this guidance is that risks and benefits are considered alongside each other in a risk-benefit assessment. This includes an assessment of the risks which, while taking into account the benefits of the activity, ensures that any precautions are practicable and proportionate and reflect the level of risk. HSE supports this guidance, as a sensible approach to risk management.” (HSE, 2012)

Prima facie, it would appear that peace has broken out, although the road may yet have further twists.

Barbican Conference on Health & Safety Reform

Public Service Events ran a one day conference entitled ‘Health and Safety Reform – reducing the burden of red tape,’ sponsored by ARCO at the Barbican on 26 April 2012. The conference was chaired by David Ball and had an impressive line-up of speakers including Andrew Miller MP (member of Löfstedt review panel), Judith Hackitt (Chair of HSE), Luise Vassie (Policy Director, IOSH), Thomas Martin (joint-MD, ARCO) and Lynda Armstrong (Chair of Trustees, BSC). In the afternoon session panel members Stephen Williams (Director of Operation Strategy and 2012 Olympic Games, HSE), Roger Bibbings (RoSPA) and Gerard Forlin QC (Cornerstone Barristers) led the debate.

Messages to emerge included strong support for the Löfstedt review findings, notably that the underlying legislation was sound but that its interpretation was sometimes problematic and could depart from good sense and proportionality. In the words of Andrew Miller, the regime was overly complex with too much emphasis on paperwork. What was to be done? HSE’s contribution to the ambitious reform programme recommended by the Löfsted review included a comprehensive review of guidance with the aim of simplification while maintaining standards. In addition the ‘Myth Buster Panel’ had been set up, chaired by Judith Hackitt herself, and had already received its first batch of over twenty myths for scrutiny. One newly-emerged myth was summarily dealt with on the spot, namely someone’s proposal on safety grounds that holly trees be removed from school environments because of the (mild) toxicity of their berries. Judith’s response was an unreserved negative!

So the pervasive message was for a risk-based and proportionate approach to safety. But how to do this? As Luise Vassie described, what is needed is scientific evidence of the magnitude of risks in order to inform priorities, and secondly to check the effectiveness of H&S interventions.

From a personal perspective the overall drift of the conference was encouraging. The need to retain the concept of ‘reasonableness’ and ‘reasonable practicability,’ the need to prioritise on the ‘real’ risks (however defined), and the need to simplify perceived administrative demands including paperwork trails and tick-boxes which were more to do with secondary (liability) risk management than the primary focus which is safety and health. However, the task is not trivial. It requires a deeper understanding of many things which are seldom discussed or alluded to in the practicing safety world, including the nature and utility of evidence, the meaning of practicability, the behaviours of people, and the role of values in decision making. Many of these things have of course been intensively analysed in academia, but it has long been the case that the flow of academic thinking into the ‘real’ world has been erratic and sluggish.

 

The risks of long distance running

This year’s London marathon saw the tragic death of Claire Squires. Subsequent media stories revealed that Claire’s was the eleventh such death since the event began in 1981. From this one can (in a sense) gauge the relative riskiness of marathon and long distance running as a sport. From 1981 until 2012 there have been about 850,000 competitors. Taking 4 hours as a rough race time means that competitors have collectively spent around 3.4 million hours on the course. A sometimes used risk statistic for comparative purposes is the death rate per 100 million hours of an activity, known as the FAR (Fatal Accident Rate). From this:

FAR for London marathon ≈ (100/3.4) x 11 ≈ 320 fatalities per 100 million hours

Budapest marathon 2011

How does this compare with other sports and other activities? Back in 1998 I made a study of fatal and non-fatal accident rates for a range of sports ranging from mountaineering to badminton (J. Sports, Exercise and Injury, 1998; 4:3-9). At that time the data showed the most dangerous sport was that categorised as ‘air sports’ which included aerobatics, gliding, hang-gliding, micro-lights, paragliding etc, and which had a FAR in the region of 200. Mountaineering was next highest coming in the range of 30-60, but has since been displaced into third place by caving which comes in at about 160. Water-related sports such as swimming, boating and fishing all have FARs of around 10 to 20, and horse riding comes in at 10. Sports such as rugby, soccer, hockey, cricket and badminton lie in or close to the range of 1 to 3.

From this (see histogram) it can be seen that marathon running is at the high risk end of the spectrum in terms of the FAR yardstick when compared with other sports. This is also true if compared even with industries operating in challenging environments, such as offshore oil and gas, where the FAR as reported by the International Association of Oil and Gas Producers is in the range of 5 to 10.

More generally, within the UK, occupational fatality rates can be estimated from HSE statistics. The average FAR for all workers is around 15, rising to around 70 in construction and 240 in agriculture. Likewise, Department for Transport statistics report FARs for various modes of travel: car 9.8; motorcycle 430; pedal cycle 38; pedestrian 15; bus or coach 0.63; rail 1.5.

So if marathon running is so risky why do it? The answer is that participation brings huge rewards in terms of physical fitness and health, psychological benefits, and social ones too. Even businesses benefit. But the debate over the relative merits and demerits of participation in these kinds of relatively extreme pursuits has been with us for thousands of years. When the London marathon was first proposed by Chris Brasher and John Disley in the 1970s there were objections, for example, that entrance should at least be restricted to club athletes. And during the earlier 1967 Boston marathon a race official attempted to physically eject Kathrine Switzer from the supposedly all-male event on the grounds that “Anything long like 800m, or even longer, God forbid, was considered dangerous ………” for women.

Times, and views, have clearly changed, and to some extent this has been unavoidable given the accumulating evidence of the health benefits of sport. Thus, in the nineteenth century, the view of Reverend Charles Wadsworth, with reference to the Oxford and Cambridge boat race, that ‘no man in a racing boat could expect to live to the age of thirty,’ was gradually proven wrong by epidemiological research which showed life expectation to be greater for rowers than non-rowers by several years.

For a concise and enthralling account of the history of beliefs surrounding the benefits or otherwise of physical activity, see Domhnall MacAuley’s ‘A history of physical activity, health and medicine’.

The debate, of course, continues. But it does illustrate the importance of collecting evidence and not being overly reliant upon subjective opinion and prior beliefs.