There's some information available about the good physical positioning of desktop PCs, and the frequency of breaks. What are the recommendations for the ergonomic use of tablets, laptops and touch screens?Reid RailtonA lot of effort went into the ergonomics of using desktop PCs and workstations when they came into widespread use in the 1970s and 80s. This didn't stop epidemics of RSI (repetitive strain injuries)/RMD (repetitive motion disorders) and carpal tunnel syndrome, but it went some way towards alleviating the problems. Following work by Systems Concepts – which also advised the Guardian when we computerised – and other experts, the Health and Safety Executive (HSE) provided a set of Display Screen Regulations, which came into force in 1992. From this point of view, the "workstation" is not just a PC or terminal, it's the whole working environment. A full workstation evaluation should include the desk and chair, any footrests and copyholders, cables, lighting, eye tests, work breaks, and training.
The Guardian, for example, installed recessed ceiling lights in our Farringdon Road offices so there was no glare on screens, and raised the floors to run cables underneath. Some of us switched to headsets instead of phones (propping a phone in the crook of your neck is a really bad idea), and also bought subsidised "computer glasses". These focus on screen distance (an arm's length) without compromising for close-up or distance work. In general, your eyes should be roughly level with the top of the screen, your arms should be roughly horizontal to the keyboard, and your feet should be flat on the floor with your hips slightly above your knees. (It may help if you have the chair seat tilted slightly forward.) You should sit up reasonably straight, with the chair supporting your back. People come in many different shapes and sizes so this usually means adjusting the height of the screen and the chair, and perhaps adding a foot rest. I use a professional computer workstation (furniture) with a slide-out keyboard tray which is below what would normally be desk height.
Either way, the aim is to find a comfortable working position that does not create neck, back or arm strains, which can become extremely painful. When computers were introduced, many people were forced to use them because their jobs now required a PC or workstation. When laptops arrived, they were often optional – some people could choose a laptop instead of a desktop – and they allowed people to work in different places, including their homes. Laptops therefore didn't meet the same level of resistance. Tom Stewart, the founder of System Concepts, tells me: "As more people started using laptops, the HSE commissioned System Concepts to do some research on the ergonomics, health and safety implications [PDF]. This research confirmed that musculoskeletal and other problems were aggravated by awkward, static postures, prolonged use without breaks, and carrying heavy computer bags (especially over one shoulder). All of these are typical of laptop users, so we recommended lighter laptops (carried in back packs with two straps), using separate keyboards and/or screens to mimic desktop configurations, and taking frequent breaks.
The HSE used this research when they updated the Display Screen Regulations." In sum, from the ergonomic point of view, you should make your laptop work more like a desktop. This may mean using a riser to lift the screen, and plugging in a separate keyboard. The unfortunate result is that, as far as I can see, we've gone backwards. In my observation, most laptop workers use them on flat desks for extended periods – even multi-billionaires do it – and this may well result in neck problems. With hotdesking, work areas are no longer configured correctly, if at all. Outside the office, many people use laptops in extremely bad ways: this includes on tables in trains (usually too high) and on their knees (bad for the neck). It's no wonder that, according to a recent survey of 1,000 UK adults (18 and over) by Dynamic Markets for Fellowes (which sells ergonomic office equipment), 79% of us say that working with mobile devices is making us ill. About 10% say that "nomadic working" has created long-term problems, and 5% have been forced to give up their jobs.
It's a very easy mistake to make, because everything is fine until it isn't. I've suffered from using laptops for extended periods, and I wrote about it in my Guardian column When Laptops Are a Pain in the Neck, in 2005. I've needed two courses of physiotherapy, at my own expense, which would have paid for a decent desktop PC. Needless to say, I now use a desktop with an ergonomic keyboard, except when travelling, and I do my prescribed neck exercises at least twice a day. I don't carry my laptop in a backpack, but I do use a bag with wheels. Having seen one backward step from desktop PCs to laptops, I suspect we're seeing another in the move from laptops to tablets and mobile phones. Indeed, some people already report suffering from "iPad neck". Dr Jack Dennerlein at the Harvard School of Public Health led a small study, which confirmed that looking down at a tablet can cause neck problems. It says: "Your neck angle makes all the difference." Dennerlein's basic tips are to prop the tablet on a stand that provides a good viewing angle, keep changing your posture, and take a break every 15 minutes.
You certainly shouldn't spend hours in a fixed position playing a mind-numbing game, nor should you let your children do the same. (You can read the full 11-page paper, which was part-funded by Microsoft during the development of its Surface tablet.) The two people I asked about tablets treat them differently. Dr Sarah Jarvis, an experienced GP and television health broadcaster, took the line that you should try to treat a tablet more like a laptop, ie like a desktop. "Treat it as a mobile computer," she said. "I've got a stand for my iPad." In particular, you should "avoid the 'vulture posture' which is particularly bad for your back." Tom Stewart said: "as an enthusiastic iPad user, I choose not to use it for prolonged typing: I don't have a keyboard for it. I prefer to change my posture regularly, and treat it a bit like a book." This reflects two different uses. If you're doing something that could be considered "content creation", such as answering emails, then treat your tablet like a PC.
If you're using it for "content consumption" then you can treat it like a book. However, it seems to me that tablets and smartphones are potentially more dangerous than either laptops or desktops, as they will more frequently be used in positions where your posture is bad for your health. The advice for desktop PC users is to take a break every hour or so, and I think you should halve that for tablets, and halve it again for smartphones. These times could be considered over-generous but, to be frank, you're not going to follow expert advice. On its excellent page on Perfect PC Posture, the British Chiropractic Association says "Never sit at the computer for more than 40 minutes; less if possible," and Dr Jack Dennerlein's advice for tablet users is "take a break every 15 minutes". I'll be impressed if you can manage one every 30 minutes. As for touch screens, I'm not aware of any ergonomic advice, but I'm also not aware of any related malaises like "iPad neck" or "Nintendo thumb" etc.