Process Safety – Useful Documentation and Resources

by | Jul 22, 2021 | Blog

Gary Horgan (CMSE Consultancy Manager at the Chris Mee Group) and his team are outlining the path for companies to ensure they are compliant with Part 8 “Explosive Atmospheres at Places of Work” of the Safety, Health & Welfare at Work (General Application) Regulations 2007 in a series of focused blogs.

This is blog number 15 in the series. This week, Danny McSweeney, discusses the useful documentation and resources that can be used to ensure companies are compliant with the legislation mentioned above.

Part 8 “Explosive Atmospheres at Places of Work” of the Safety, Health & Welfare at Work (General Application) Regulations 2007

Seeing as these blogs are focused around ensuring companies are compliant with Part 8 of “Explosive Atmospheres at Places of Work”, it is natural that this legislation is the most important piece of documentation to be used to ensure a company’s compliance. The full text of the legislation is available for free online. Here 

Additionally, the Irish Health and Safety Authority (HSA) have produced a document which gives further guidance in relation to the prevention of occupational accident or ill health resulting from an explosive atmosphere at work. This document is freely available online Here

 

Engineering Standards: EN 60079

There are a range of engineering standards which relate to equipment standards and safe working practices for explosive atmospheres at workplaces.

One of the key series of standards covering this area is IEC 60079, which are published as a European Standard as EN 60079. These standards are an extremely useful resource when referring to the classification of hazardous areas, and the engineering standards expected within the presence of an explosive atmosphere at work.

While there are over 30 individual standards that make up this series, the three following standards are those which we would most often refer to during our Explosion Safety consultancy work. These are:

  • Part 10: Explosive atmospheres. Classification of areas.
    • Part 10-1: Explosive gas atmospheres,
    • Part 10-2: Combustible dust atmospheres
  • Part 14: Electrical apparatus for explosive gas atmospheres. Electrical installations in hazardous areas.
  • Part 17: Electrical apparatus for explosive gas atmospheres. Inspection and maintenance of electrical installations in hazardous areas.

As can be seen, Part 10 explores how one would go about classifying an area as a hazardous zone. There are different Hazardous Area Classifications (HACs) with regards to gas atmospheres and dust atmospheres; part 10-1 refers to gas atmospheres and part 10-2 refers to combustible dust atmospheres. Part 14 explores the type of equipment required in all different types of hazardous zones, while Part 17 gives guidance on the maintenance of said equipment.

These standards are available for purchase from any of the national standards authorities. The British Standards Institute (BSI) link is here.

Industry-Specific Guidance

While the documentation mentioned above is good for general application, some companies may need industry specific guidance to further reduce the risk of an incident occurring due to explosive atmospheres.

One example of this would be the Energy Institute Model code of safe practice Part 15: Area classification code for installations handling flammable fluids (commonly known as EI 15). It is recognised internationally as being the de-facto guidance for calculating hazardous zone areas in the petroleum industry.

It provides a demonstrable methodology for determining hazard radii, and is applicable to all installations handling flammable fluids. It gives guidance on the classification of regions around equipment handling or storing flammable fluids, and provides a basis for both the correct selection of fixed electrical equipment and the location of other fixed sources of ignition in those areas.

EI 15 is available online for purchase Here.

 

Another useful resource is the Institute of Gas Engineers & Managers IGEM/SR/25. This is a standard which compliments BS EN 60079-10-1 by providing detailed requirements for the hazardous area classification of permanent and temporary natural gas installations.

It applies to all natural gas installations, although other standards may be more readily applied for installations downstream of an emergency control valve. In general, it will not be less conservative than these other standards and therefore it may be used for any natural gas installation. It applies to liquid free natural gas within specific property ranges. This standard applies to any potential release of natural gas except those that may be caused by catastrophic failure such as rupture of a process vessel or pipeline, component failure and similar rare events that are not predictable.

https://www.igem.org.uk/technical-services/technical-gas-standards/safety/igem-sr-25-edition-2-hazardous-area-classification-of-natural-gas-installations/

 

Other Useful Resources – GESTIS-DUST-EX database

While explosivity data for flammable liquids, vapours and gases can usually be found in their associated Safety Data Sheet, in our experience this is much less common for combustible dusts and powders.

Whilst we would recommend companies undertake testing of dusts/powders as a first preference to gather this data, where this is not practicable, then the GESTIS-DUST-EX database is a very useful and comprehensive source of explosivity data for common combustible dusts and powders.

The GESTIS-DUST-EX database has been collated by German Social Accident Insurance (DGUV). It includes combustion and explosion characteristics of more than 7,000 dust samples from virtually all sectors of industry, determined as a basis for the safe handling of combustible dusts and for the planning of preventive and protective measures against dust explosions in dust-generating and processing plants. The database includes information taken from an earlier report – “Combustion and explosion characteristics of dusts (BIA-Report 13/97)”.

The database is freely available and searchable online here.