Until now there’s been no standard providing criteria to help determine the placement or number of flame and gas detection devices needed to optimize safety in an explosive or toxic atmosphere. This blog post discusses the new British Standard that is plugging that gap.
It’s fair to say that there are a number of standards covering explosive atmospheres. The European 60079 series alone is extensive and wide-ranging. It includes, for example, BS EN 60079-29-2:2015 Explosive atmospheres. Gas detectors. Selection, installation, use and maintenance of detectors for flammable gases and oxygen. This standard deals with – as the name points out – choosing, installing, using and maintaining flame and gas (F&G) detectors. Nevertheless it – in common with all other standards – doesn’t talk about the important subject of detection mapping using software tools and techniques.
Moreover recent years have seen an increase in the number of commercially available mapping tools. This has tended to exacerbate the issue. Because as much as these tools are useful, there are still no generally agreed principles or guidance as to what it is that they should be achieving.
To fill that deficit we’ve now published an all-new British Standard that will complement and support existing explosive atmosphere standards. It is: BS 60080:2020 Explosive and toxic atmospheres: Hazard detection mapping – Guidance on the placement of permanently installed flame and gas detection devices using software tools and other techniques.
Permanently installed F&G detectors
BS 60080:2020 gives guidance on the placement of permanently installed F&G detectors. It defines permanently installed detection systems as including optical flame detection (including ultraviolet, infrared and visual), flammable gas/vapour detection and toxic gas detection.
The standard covers the setting of performance standards for coverage, placement of devices and technology selection. And it provides guidance on the most commonly used methods of mapping and/or modelling – prescriptive, volumetric and scenario-based. It also provides guidance on operations, maintenance and the availability/reliability of the system to complement relevant standards.
It’s relevant to applications where optical flame detection is used as a means of detecting flaming fires in internal and external environments; where a gas detection system is used as a method of explosion protection; where the hazard arises from the release or accumulation of explosive gases and vapours and where the hazard arises from the release or accumulation of toxic gases.
Increasing the level of safety
The standard was written to be used by manufacturers, retailers and distributors of detection devices and software, as well as engineering companies and engineers tasked with implementing a detection system. They’re responsible for the detection layout and implementation of the system but rely on company or end-user guidance on what targets to meet and which rarely exist. Before this standard existed, this resulted in inconsistent designs across similar sites which may even be operated by the same end user. Analysing adequacy is also difficult, as this is typically based on the experiences of the individual tasked with generating the layout.
The standard will also be used by consultants and auditors who’re brought in to conduct third-party reviews, and who themselves need a design guide with which to assess adequacy or otherwise. (To date consultancies are prepared to sign off on systems but state that since no standard exists on which to base a finding of adequacy, they accept no liability if, in fact, the system is not fit for purpose.)
Certification bodies will also use the new standard as it gives them a checklist that they can certify compliance against.
Secondary users will be insurance companies. It can form part of their checklist – i.e. “gas detection systems installed in compliance with....” It can be used by regulators in the same way. Academic institutions can use the standard in their courses. Finally the judicial system may be able to turn to the standard as a model of best practice in the event of accidents, injuries or deaths as a result of explosive atmosphere explosions.
And at the end of the day, that usage vividly highlights the purpose of this new standard. It exists to increase the level of safety in explosive atmospheres in order to protect those working on sites, as well as the general public and the environment in the vicinity of sites. The standard will tell users what an acceptable minimum level of safety is in respect of explosive atmospheres, so that they can achieve it.
