Think of traumatic images as if they were radiation — with an objective, unavoidable impact on the body and psyche. Like nuclear workers, journalists have a job to do. But as with radiation, minimise exposure.

Most people cope well, on the whole, with trauma. But emotional distress is not unusual, and there should be no stigma.

Different individuals, for many different reasons, have varying levels of tolerance. Some may cope well. Others' ability to cope may have been worn down over the years.

Others may have personal experience — for example young children — which allows particular images to get through their defences.

Handling the material:

•  No-one should need, or be expected, to watch video images that will never be broadcast. Teams and their managers need to agree it's OK to switch monitors off, or at least to look away, when a particularly violent feed is coming in. And accept the risk of occasionally missing a story.

•  The sound can be the worst. For those on the team who do have to watch what comes in, and make choices about editing, at least make sure the sound is switched off.

•  Agencies should consider whether it is appropriate or necessary at all to feed images that will never be broadcast.

•  If individual broadcasters or publishers still wish to receive this material, it can be encrypted or fed directly.

•  Picture and news agencies feeding video or images of violence should clearly signpost such material well in advance. It should never be played out in the middle of a general feed.

•  Whenever graphic videos are about to be fed (including repeats), duty editors should announce a health warning over their public address system. This gives all the opportunity, once the feed is under way, to look away.

•  Editors, programmes and the newsroom need to be educated/informed about precautions being taken by those taking in picture and video feeds — and to be patient and understanding even when under pressure.

•  Organisations and newsrooms should agree clear guidelines on where and whether graphic material is stored, and who will ensure on any shift that such material cannot be inadvertently viewed.

•  Such material should be recorded only once .

The Workplace:

•  Teams must be educated about normal responses to trauma — how different people cope differently, how the impact can accumulate over time.

•  People dealing with this material should be encouraged to talk to each other about their experiences. After a particularly bad period, get the team together to take stock.

•  Workplaces that deal with violent imagery should wherever possible have physical windows to the outside world, even if that's only to a patch of real sky. Failing that, a large plasma screen can be set up with a live “weathercam” image of the real outside world.

•  These workplaces, more than others, need plants and a sense of nature. At times of stress, the human body and psyche are naturally soothed by greenery and nature.

•  Those dealing with these images must take frequent screen breaks. Copy the smokers and make a point of stepping regularly outside the building for some fresh air. Careful, though. Nicotine — and coffee — can heighten physiological arousal and anxiety.