Zone 1 equipment plays an important role in protecting hazardous areas against occasional risks, for example due to the accidental or unexpected release of a cloud of gas.

While Zone 0 equipment is used in the presence of ongoing hazards and Zone 2 equipment is used where any release is likely to involve only low concentrations of gas for a short period of time, Zone 1 equipment arguably faces the toughest challenge.

It must be able to cope with relatively high concentrations of hazardous materials, which are only occasionally released, and should act to minimise the impact of any such leak.

An article in the January 2017 quality assurance journal Calitatea looks at how modern software makes it easier to calculate the scale of a combustible gas leak – and how hazardous area equipment should tackle it.

In particular, Zone 1 equipment should act to contain any leak while preventing sources of ignition that could spark a catastrophic explosion.This doesn’t just mean reducing the amount of vapour that leaks; it also includes reducing the frequency of leaks, and the duration over which each incident lasts.

This doesn’t just mean reducing the amount of vapour that leaks; it also includes reducing the frequency of leaks, and the duration over which each incident lasts.

Together, these fundamental protections allow Zone 1 equipment to create a physical barrier, containing any leaks and ideally preventing them from occurring in the first place, and reducing the size and impact of the resultant hazardous areas.