Hold the front page!  Employees may face alcohol testing at work shock horror, etc., according to Tuesday’s Metro.

Apparently a new finger-touch testing device is now ready for launch, which can give a red or green light for alcohol in the blood stream in just 10 seconds, allowing for the “processing” of up to 300 employees per hour (though if you really have that many people on your staff whose drinking habits you are worried about, you have altogether bigger issues than this particular piece of kit could ever resolve).   Users can set their own threshold levels, according to the manufacturers, and the device can be used for industries from transport and leisure to the National Health Service and banking.

You could probably make a case for routine alcohol testing in some safety-critical roles – airline pilots, oil-rig workers and the chap on watch at Sellafield – but otherwise it is hard to disagree with Dave Prentis, General Secretary of Trade Union UNISON, who sees this as “a sledgehammer to crack a nut”.   However, Metro reports his then losing that proper sense of perspective and continuing “If workers have a problem with alcohol, their employer should not be relying on a gadget to entrap them, but should be providing them with proper support”.   All well and good, Mr Prentis, but subject to a number of potentially fatal flaws.    Firstly, you do not have to have “a problem with alcohol” to be dangerously under the influence on one day.  Second, it may only take one day for there to be some serious accident or injury arising from your being in that state.  Third, alcohol begins to impair your faculties almost immediately, and well before the point where this would be visible to the untrained eye.   Last, above all, this is not about “entrapment” – that would be leading your employees to believe that reeling into work on the fumes of the night before is okay, and then nailing them for it.   The existence of a quick pass-or-fail test on a regular basis should be a deterrent, and not a temptation.

However, that does beg the question of what you could do with an employee who got a red light.  Is it automatically a warning, or just bundling him off to counselling for some of Mr Prentis’ “proper support”.  The problem lies in identifying what a red light actually means, and then establishing some connection between the alcohol level and the job.   Strictly speaking, what dictates fitness to perform a role is not the precise level of alcohol in the system, but each individual’s physiological response to it.    The number of roles where even the most millimetric impairment is truly and reasonably unacceptable is miniscule.  Therefore in all other cases, the employer may find that it is taking action against red-lighters who are far more physically capable than some greens who have only a few milligrams of alcohol less coursing round the system.  Blood-alcohol readings may be affected by weight, body mass index, gender and parallel medications or oral contraceptives, and that is even before we get on to the question of the actual impact of those readings on the person’s fitness for the role.

So what we really have here is not actually a panacea or easy answer to alcohol-related risks in the workplace, but merely a device which might, in some circumstances, trigger a certain line of enquiry.  It is nowhere close to sufficient by itself to determine whether someone should keep their job, be subject to disciplinary action or be treated as “having a problem”.  Moreover, employers considering using the system as a deterrent will have to bear in mind that their own credibility and their ability to rely on the results will depend upon their setting a suitable threshold level.   If set unrealistically low, you might as well not bother.