Mitigating the risks and impact of explosions

IEC Standards help reduce the number of casualties from accidental industrial explosions

By Morand Fachot

Explosions in a wide range of industrial or other installations can be caused by the wrong or faulty equipment, and/or by poor operating procedures or mistakes. Risks can be significantly reduced if equipment and systems that meet IEC Standards developed by IEC Technical Committee (TC) 31: Equipment for explosive environments, are used. 

Rescue efforts at Soma mine in Turkey 2014 An explosion at an underground coal mine in Soma, Turkey, caused a fire that killed 301 miners, the worst mine disaster in Turkey's history (Photo: Mustafa Karaman/Wikipedia)

Meeting an important and old need

For most people catastrophic explosions are associated with certain so-called Ex environments, like the oil and gas or chemical industries, mines and many more sectors. They frequently result in large number of casualties and/or significant and costly environmental damage.

The explosion that destroyed the North Sea Piper Alpha oil and gas offshore platform in July 1988 resulted in the death of 167 workers and damage in excess of USD 1 500 million at the time.

The explosion of the Deepwater Horizon drilling platform in the Gulf of Mexico in April 2010 killed 11 workers, caused major environmental damage that required a huge clean-up operation costing billions of dollars.

Hundreds have also died in explosion-related mining accidents across the world over the years, the worst recent one killed over 300 miners in Soma, Turkey, in 2014.

Accidents caused by explosions happen also in chemical plants, grain silos, sugar refineries and many other sites, such as laboratories.

To prevent these accidents, specially designed and properly installed and maintained equipment and systems are essential. International Standards for these are prepared by IEC TC 31. 

Meeting an inherent need

IEC TC 31 was established in 1948 “to address the need to develop techniques for ensuring electrical equipment would not provide an explosion risk when used in explosive atmospheres involving gases, vapours and mists.”

The TC scope has been expanded over the years to meet additional needs and “to include classification, installation requirements and combustible dusts.”

The current structure of TC 31 includes three Subcommittees (SCs):

  • SC 31G: Intrinsically-safe apparatus
  • SC 31J: Classification of Hazardous Areas and installation requirements
  • SC 31M: Non-electrical equipment and protective systems for explosive atmospheres

TC 31 has also 12 Working Groups that cover different aspects, such as electric machines (motors and generators), dusts, gas/dust hybrid mixtures, batteries in equipment for explosive atmospheres, etc.

As a result TC 31 is a provider of Standards to a number of other IEC TCs and maintains liaisons with committees from other organizations such as ISO/TC 197 WG 13: Hydrogen Detectors, a TC of the International Organization for Standardization (ISO), or the Petroleum and Chemical Industry Committee (PCIC) of the Institute of Electrical and Electronics Engineers (IEEE). 

Large number of experts, extensive portfolio of publications

More than 510 experts from 39 National Committees take part in the TC’s work. The TC and its three SCs had issued 71 publications as of May 2017, and their current Work Programme includes development work on 19 other publications (including newer versions of existing ones). These Standards are also adopted in various countries at the national and regional level, either in whole (without differences), or in part (with identified differences). 

All-inclusive ecosystem

Protecting installations and people against risks from explosive atmospheres is not only the result of comprehensive standardization work from IEC TC 31, its SCs and WGs. It is also due, to a great extent, to the work of the IEC System for Certification to Standards relating to Equipment for use in Explosive (Ex) Atmospheres, IECEx.

IECEx provides the following:

  • a robust and credible system for the operation of Standardized Certification Schemes
  • a dedicated IECEx website
  • an on-Line Certificate of Conformity System in real time
  • it serves as a committee/forum for the industry and stakeholders to have a voice in the running of the IECEx Schemes

Stakeholders include both Participants group and Users group:

The Participants group, comprise, for instance:

  • member bodies of the IECEx System
  • certification bodies
  • testing laboratories
  • accreditation bodies
  • manufacturers

The Users group consists of all those that have the need to correctly select equipment and  services, such as:

  • end users
  • consulting engineers
  • regulators
  • inspectors
  • repairers
  • other government agencies (trade, technical infrastructure, foreign and domestic policy)
  • other international standards organizations

The purpose of the IECEx System is to:

  • reduce testing and certification costs to manufacturers
  • reduce time to market
  • achieve international confidence in the product assessment process 

The Global Solution for Ex environments

Taken together, standardization work by IEC TC 31 and the IECEx system provide a global comprehensive solution to address many of the risks found in Ex environments. Theirs is a work in constant development as new risks arise and as new solutions are found for these and for older risks.

Gallery
Deepwater oilrig The explosion of the Deepwater Horizon drilling platform killed 11 and caused major environmental damage in the Gulf of Mexico
Rescue efforts at Soma mine in Turkey 2014 An explosion at an underground coal mine in Soma, Turkey, caused a fire that killed 301 miners, the worst mine disaster in Turkey's history (Photo: Mustafa Karaman/Wikipedia)
Georgia sugar refinery explosion 2008 Thirteen people were killed and 40 injured when a dust explosion occurred at a Georgia (US) sugar refinery (Photo: U.S. Chemical Safety and Hazard Investigation Board)