When it comes to workplace safety, the average office might look like fairly benign environment. But beware! Even chairs can be hazard. And as for the innocent looking mouse. It may be quietly leading you into musculo-skeletal disaster zone.
Problems associated with occupational overuse syndrome (OOS) may be well known and means of avoiding it equally well documented, but the cost of ACC claims for OOS conditions continues to climb. And the cost to business in lost productivity from office-related injuries runs into the many millions and an increasing percentage of the nation’s total annual $3 billion-plus industry accident bill.
New claims for 2002/03 totalled 2705 (2460 the previous year) and cost $11.65 million ($10.4 million). Ongoing claims add up to another $18 million.
These arise from range of occupations including office workers and professionals, trades, sales and service workers, agriculture, fisheries and plant/machinery operators. And, given that claims have to be for specific injury (such as carpal tunnel syndrome or epicondylitis), they probably only represent the sharp tip of the discomfort iceberg.
It is estimated that in the United States “cumulative trauma disorders” or repetitive stress injuries are the fastest growing on-the-job injuries, annually costing businesses more than $15 billion in workers’ compensation.
Humans are simply not designed for continuous repetitive activity and many workplaces are ill equipped for the people using them. True, some more enlightened employers run ergonomic assessments of individual workstations, but it’s usually case of one size fits all. Tall folk get to hunch over standard-sized desk and the shorties, if they’re lucky, get standard-issue footstool.
The trend toward work mobility brings other problems. Laptops, for instance, are great for short-haul work but the low-level screen and cramped keyboard produces less-than-optimum posture for long periods of work. high proportion of telecommuters or home-office workers might, at best, miss out on formal ergonomic assessments or, at worst, make do with corner of the kitchen table.
Growing awareness of the problems has spawned range of ergonomic office products from super adjustable chairs or desks to software that either discretely reminds users they need keyboard break or, enforces it by blacking out the screen.
Continuing improvement of voice recognition systems promises future in which users can simply chat to computers instead of using keyboards. Meanwhile one American company has come up with “keyless keyboard” that employs pair of ergonomically sculpted domes to type characters with the same precision as pressing key.
Other innovations plan to kill off the mouse, replacing it with pressure strips or foot pedals to scroll down pages or move things around the screen.
Even the average everyday desk could be up for an overhaul. New Zealand company recently unveiled its prototype for completely new chair-based computer system, la Starship Enterprise. The “zero gravity chair” developed by Petone-based Vision provides neck to ankle support in curved design that “exactly matches the position the body assumes when floating weightless in space”.
Back on planet earth ergonomic solutions don’t just revolve around chair shape and body posture. They take into account bundle of operational and environmental factors, all of which put people at the centre. They look at the interfaces between user/equipment, user/workspace (including seating, workbench height etc), user/environment (noise, heat, lighting etc), and user/organisation and question whether the work culture supports and encourages healthy work practices.
There really isn’t much excuse any more not to get it right. An Occupational Safety and Health (OSH) Code of Practice issued three years ago provides guidelines for safe practice and the ACC website has detailed advice on such things as equipment use, posture, muscle-relaxing exercises, operational practice, environmental issues and stress.
The whole manual hazard identification system is well documented and encourages broad perspective, says ergonomics specialist Marion Edwin. “You don’t just look at the desk and computer. You need to take into account factors including how the job is organised, whether software can reduce mouse abuse, how and when work breaks are taken, or whether there is enough postural and task variation.”
Remaining in one position for too long restricts blood flow and leads to fatigue. Tension speeds up the process. It is, therefore, good idea to make frequent small adjustments to posture. At the state-of-the-art end of postural variation are desks that can be adjusted to sit or stand at.
Variation is key issue for anyone doing repetitive task, particularly when it’s intensive, says Edwin. “People doing continual keyboarding or data entry need to take micro-pauses every three to five minutes, what I call ‘stop, drop and flop’. Drop your arms into your lap or by your side, take deep breath and just let them flop – it helps return blood flow to the muscle.”
It’s often matter of learning to use natural pauses such as when the computer screen is refreshing, during save, or download. Instead of waiting, poised for the next thing, slip briefly into flop mode, she suggests.
Electronic break reminders work for some though it depends on task complexity. Having your train of thought continually interrupted may not do whole lot for stress levels. And while “ergonomic” equipment definitely has its place, Edwin reckons it can sometimes be too much of good thing. “There are huge amounts of that sort of gear around and some of it is just trendy office junk,” she adds. “Not that I haven’t recommended it at various times but some employers have all the office junk and are still badly set up because they haven’t addressed the basics. If your desk and workstation is set up for you and is good fit from the outset, then you’re less likely to need things like foot stools.”
A classic problem is desk height. Desks are usually 720mm high. And that’s higher than what’s generally recommended for safe use of visual display unit. ACC guidelines indicate desk height adjustability that starts from 580mm. “Yet you still see lot of places that have all the fancy equipment – along with fixed desk heights of 720mm,” says Edwin.
Sitting someone optimally depends on various aspects of their anatomy including length of legs, sitting height, length of arms and so on. Start with the most comfortable sitting position and work from there. But usually it is done in reverse according to Edwin. People sit at higher-than-ideal desk, crank up the chair, then use footstool.
The answer is education.
Users must understand the risks, the hazards and the strategies for working around them. If someone is away from the office and working for extended periods on laptop they may need plug-ins, like keyboard or mouse, and know how to place the screen in position that doesn’t wreck their neck.
“If they don’t know that, maybe the employer hasn’t done such good job of educating the worker to manage the hazards,” says Edwin.
Education must be backed by good systems, support and work culture that encourages healthy practice.
“It’s not enough to say, we educated people so they should know,” says Edwin. “Education has to be backed up with appropriate systems and an appropriate physical environment. Then the job has to be organised in such way that it can be done safely.”
Five mouse-taming tips
1. Move the mouse from elbow rather than wrist.
2. Position it so your arm is raised no higher than elbow level.
3. Don’t use mouse by stretching to the desk or out one side of the keyboard.
4. Avoid restricting arm movements – chair arms or wrist rests can restrict blood flow and encourage wrist-flicking mouse movements.
5. Choose flatter mouse design to reduce wrist extension.
Detailed advice on safe practice for computer-using desk jockeys can be fou
