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ALARP what is it

In recent times I have seen some suggestions that the idea of ALARP is a license to pollute, despoil and irradiate. I hold the view that the idea of ALARP is quite the reverse. ALARP is As Low As Reasonably Possible.

The great problem is that all human activities and technologies carry some form of risk of mishap or misadventure

Coal mining is associated with many industrial accidents where miners are crushed, burnt, gassed, entombed or killed in other ways. Sadly in Wales many years ago a heap of mining waste smothered a primary school killing many children at a place called Abervan. I will add the comment that buried alive accidents are very “low tech”, quiet and deadly. Many people have falls, car crashes or electric shocks which injure them sometimes some people die from these accidents. But very few people ever survive being buried alive and as a result it is an under appreciated type of accident.

Writing with a pencil can lead to writers cramp and you might get a splinter from the wood of a pencil.

Cutting down trees for firewood can lead to erosion and other untoward modifications of the environment.

Eating food carries a small but finite risk of death by food poisoning.

Folk dancing brings a risk of bodily injury (twisting an ankle while doing the “nervous breakdown” dance hurts a lot)

Dog ownership brings the risk of coming onto contact with ticks and also dog bites. I would strongly suggest never reaching under the bed to handle a frightened dog.

Getting out of bed in the morning introduces the risk that you will slip on the floor and smash your head on the wall

Staying in bed all day brings a risk of a heart attack caused by a very lazy lifestyle and the roof of the house might just fall in on you.

I could go on and on with more examples of risks which exist in industry and everyday life, the ALARP principle is that even if the law of the land does not ban method A of work and if a safer method B (which is less easy) exists then the safer method (B) should be used.

I will give you an example, at one school the children who bring packed lunches are required to stack the lunches on the window ledge in full view of the glaring sun. This is method A, at a second school the children are required to hand over their packed lunches at the start of the day. These lunches are placed in a refrigerator all morning for food hygiene reasons, at lunch time the packed lunches are returned to the children. Call this method B.

While no law might exists to ban method A, if method B significantly lowers the risk of food poisoning then even if method B costs more to use then the As Low As Reasonably Possible principle suggests method B should be used.

While chidren’s lunch boxes are a simple clear cut example there are examples which are less clear. For example a chemist sets out to make a chemical. Goodness knows what it might be, it could for all I know be a wonder drug which makes children tidy their bedrooms, cures ugliness and makes the birds sing more sweetly in the trees. OK I have to have the occasional flight of fantasy back to normal operation now.

One of the key steps in the production process might require the use of a carcinogenic reagent such as hydrazine and is done at room temperature in a small glass beaker. It occurs in five minutes, is stable to air, gives a 99 % yield and generates 10 grams of waste for every kilo of the drug which is made.

The alternative method might exist which uses nice green friendly reagent (banana skins) but this method generates 100 grams of waste for every kilo of the drug made, gives a 99 % yield, requires that air is excluded, occurs at 200 oC and needs to be done in an autoclave (fancy term for pressure cooker) at 200 bar. Here we now need to try to weigh up the threat posed by the autoclave being under preasure against the chemical threat posed by the hydrazine.


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