Last month's European Health and Safety Week saw renewed promotion of a technique for flagging up workers' health problems, especially musculoskeletal disorders (MSDs), that has been used successfully by trade unions since the mid 1990s. It's a simple, usually pictorial approach that can work particularly well with people whose first language is not English and has the rare distinction of giving employees some entertainment in a health and safety exercise.

The technique is "body mapping" - a technique developed in the 1970s at Nottingham University and pioneered by unions in Spain, the United States and Mexico to encourage workers to report ill-health symptoms. By 1996, bodymapping was at the top of the Canadian union movement's safety agenda and five years later unions in this country were actively promoting it.

The technique involves workers creating a "body map" of health problems by sticking flags on an outline diagram of the human body to indicate any areas where they are experiencing pain or discomfort. Employers can then use this information to identify trends, analyse work processes and put in place measures to reduce hazards before workers' health is damaged.

Ouch! stickers

The effects of the working environment on workers' health are difficult to establish: workers often dismiss minor health problems as insignificant or unrelated to their jobs, so it can take some time to make a link between the symptom and the workplace. Other workers may be reluctant to self-report for fear of losing their jobs (see Please speak up).

The thinking behind body mapping is that if workers doing a job pool information about any health problem they are experiencing - regardless of whether they think it is caused by their work - patterns can emerge that might otherwise go undetected.

There are various different approaches to body mapping. The simplest model might use two large outlines of the human body - front and back views - on which workers mark (using stickers or a pen) any areas they are feeling soreness or pain that might be attributable to work. Colour-coding can be used to indicate levels of pain or different types of symptom; for example, physical discomfort, stress/anxiety and ongoing issues such as reproductive problems. In some exercises, workers might be asked to add notes to the diagrams explaining why they have flagged up an area.

There are numerous variations on the technique. A task-based approach helps to link the body mapping closely to the work: a worker mimes a particular operation and the others apply stickers ("ouch! stickers") to their colleague's body to identify problem areas and symptoms.

Whatever the details of the exercise, a common requirement is that workers in a body-mapping session should be doing the same or very similar jobs, otherwise the results won't be meaningful.

"The best body-mapping sessions are where you get a group of workers together - who do a similar kind of work - for an hour and a half, or two hours even, and get them to talk through the exercise together," says Doug Russell, health and safety officer at the Union of Shop, Distributive and Allied Workers (Usdaw). "Because it's by talking to each other that the ideas come out."

Different jobs will generate different "maps". A body map by a group of drivers might be expected to show clusters of flags around the lower back area (as a result of extended periods of sitting or poor driving position or posture), the legs and wrist (from pedal use and gear changes) and stomach (as a result of digestive problems caused by inadequate or irregular meal breaks). A body map for a group of office workers might show clusters around the wrists, shoulders and neck (as a result of DSE use or stress) or around the eyes (indicating eye strain from prolonged screen work).

Armed with this straightforward, graphical information, the employer or safety manager can take action, whether it be training, changes to work patterns or processes, or a review of the equipment in use.

Keeping it simple

Workers usually know their jobs and the associated risks better than anyone else, but they may lack the opportunity or inclination to discuss concerns with each other or their managers. For the beleaguered safety manager trying to encourage workers to take an interest in, and responsibility for, their own and their colleagues' safety and health, body mapping can be a useful tool. It can promote awareness of health and safety risks and lead to workers thinking of ways they can help control risks and prevent injuries.

"Central to the exercise is drawing on people's experience and doing it in a collective way," explains Russell. "It helps people to identify the aches and pains that might well be work-related because more than one person is concerned. People often tend to think it's just them getting old or them being a bit unfit. But when you actually get them all together and they all say that working on that particular machine or working on that particular checkout is causing them aches and pains in the shoulder, you can see that there's something there and start to try to figure out what it is.

"Not only can workers identify the issues; they can often identify the practical solutions as well."

A key appeal of the method is its simplicity. "It's a relatively straightforward way to gather information about aches and pains, cuts, bumps, bruises, headaches, eyestrain - a whole wide range of potential occupational health issues," confirms Phil Madelin, national health and safety officer at the Public and Commercial Services Union (PCS). "One way that it works very well is if you couple it with an awareness-raising exercise. I quite often recommend it to people as part of a range of inspection techniques in workplaces."

Workers' playtime

Another feature of the technique is that it can be fun. If health and safety has an image problem, then an interactive group session with a handful of felt-tip pens and life-size human outlines can go a surprisingly long way to changing workers' perceptions. Madelin suggests one way of carrying out a body-mapping exercise would be during the tea break of a safety meeting, so workers can participate in an informal way.

As a largely visual exercise, body mapping has the advantage that it overcomes literacy issues and language barriers. Concerns about protecting the welfare of migrant workers usually focus on communicating safety information to protect them from dangerous situations. Longer-term health issues among migrant workers are a more complicated matter. "With body mapping, you don't actually have to be able to read or write to show where you're having aches and pains," notes Mike Gray, head of the ergonomics team at the HSE.

Biased picture

It's important to understand the limitations of the technique before you start. Madelin warns that body mapping is a "first step" in identifying potential occupational health risks, but it's not the panacea.

"It's not scientific," he stresses. "Just because you've got a lot of people reporting the same symptoms, that doesn't automatically mean work must be causing it. It's quite possible to have a whole number of people reporting the same sort of ache, pain or strain for a variety of completely non-work-related reasons. So the results have to be interpreted with some caution."

What body mapping does do, Madelin argues, is to encourage safety reps, employers and employees to think beyond physical hazards - trailing wires, worn carpets, objects stored precariously at height - to less-visible and often neglected health issues, such as repetitive strain injury caused by excessive hours in front of a PC.

To what extent the information reported remains private to the individual depends on the approach. A group session will require workers to be open about health concerns in front of colleagues, which some employees may find intrusive. An informal exercise that takes place in a meeting might be more anonymous, especially if workers don't have to put their names by their responses. For complete anonymity, individual maps can be circulated for workers to complete and the responses collated.

This survey-type approach removes the opportunity for open discussion, but it has its advantages. "A set of questions to go alongside the tool has been developed," explains Mike Gray, "to try to standardise the things people are describing."

These questions are based on the Nordic musculoskeletal questionnaire. Some experts believe they help focus employees' answers and provide more useful information by requiring respondents to indicate - using tick-boxes - how recently they have experienced the pain, whether the pain has prevented them carrying out normal activities and whether the pain seems to be unrelated to work, made worse by work or caused by work.

"I think the way it should be used is to monitor the effectiveness of interventions," says Gray; follow-up surveys will indicate whether measures introduced to reduce MSD problems, for example, have been successful. What is important though, he cautions, is that a lot of people fill it in. "If it's just the people who are moaning anyway, you start to get a biased picture of what's going on," he explains.

---

A picture paints a thousand words

The TUC has reported on a number of successful body mapping exercises (see www.tuc.org.uk/h_and_s/tuc-3813-f0.cfm and www.tuc.org.uk/h_and_s/tuc-12233-f0.cfm).

• Workers in a bakery reported in a body-mapping course that they were suffering back injuries and strains. A review of working practices led to the introduction of new, smaller baskets that hold less product, and improvements in job rotation and task variety.
   
• A body-mapping exercise conducted among a group of Fire Brigades Union members identified unreported bladder problems. Further investigation revealed that inadequate facilities were to blame: the firefighters had to go down a flight of stairs, outside and through a courtyard in the middle of the night to get to the only toilet.
   
• A small group of people working in residential social services identified through body mapping that each of the attendees was gaining excessive weight. The group determined this was mainly a result of irregular work patterns (shifts and long hours) and dealing with challenging clients.

10 years on

More than a decade after it started to catch the imagination of safety campaigners in North America and the UK, body mapping has had some notable successes (see boxes) and Gray says the HSE encourages employers to try it, especially with "problematic jobs".

"The biggest barrier to body mapping is the logistics of getting people to spend some time away from work to do it," says Usdaw's Russell. "But it has certainly worked in sectors where it's been trialled."

Where it has been difficult to get workers together to carry out an exercise, Russell has used questionnaires and informal surveys instead. "But they don't work as well," he believes, "because you don't get the interchange of information between the different people."

Phil Madelin likens the technique to the HSE's stress indicator tool, "which is 35 questions getting people's subjective views on a situation, yet highlights areas for further investigation".

"I think employers should be as prepared to respond to indicators from body mapping as they are to any other indicators of a potential health and safety crisis," he says. "But what I wouldn't want is to see safety reps going in, waving a body map and saying, 'You've got an RSI problem - you've got to sort it out.'

"What I would expect a safety rep to do is to say, 'We conducted this exercise; it highlighted a number of people complaining of these sorts of potential occupational health issues. Obviously we're not saying they all are linked to work, but we think it merits further investigation. How can we work together?'"

As part of 2007's European Health and Safety Week campaign on MSDs, the TUC and HSE produced a body-mapping tool that takes the form of a questionnaire (as described above). This is available to download at www.hse.gov.uk/campaigns/euroweek/pdfs/bodymapping.pdf

More information on body mapping is available on the Hazards website at www.hazards.org/diyresearch, on the PCS website at www.pcs.org.uk/Templates/Internal.asp?NodeID=884235 and on the Usdaw website at www.usdaw.org.uk/getactive/resource_library/files/RLFBodyMap/BodyMapping.pdf
An Usdaw report on body mapping and back pain among women members, Charting Back Pain, is available at www.usdaw.org.uk/healthandsafety/toolkit/1133528995_32318.html