Safety Alert – Fixed and portable angle grinders pose hot work hazard

Findings from Marine Accident Investigation Branch (MAIB) “Report on the investigation of a fire in the engine room on the suction dredger Arco Avon 12 miles off the coast of Great Yarmouth resulting in one fatality on 18 August 2015″ has indicated that the hot work hazard of sparks generated by the use of fixed and portable angle grinders is often overlooked.

The report identified that even though guidance published by the HSE in “HSG17 Safety in the use of abrasive wheels, Revised in line with the Provision and Use of Work Equipment Regulations 1998 (PUWER 98),” is comprehensive it fails to reference the hazards created by the sparks generated during grinder operations.

Furthermore where such hazards exist appropriate PPE should be selected. The report identified that the overalls available for use on the ship in question were not  of an adequate standard given the fire risk.

Although not referred to in its guidance (HSG17), in 2004 the HSE has produced a research report (HSE Research Report 222), which studied the ignition and flame spread of clothing fabrics subjected to angle grinder sparks. The report studied natural and synthetic fabrics and both untreated and fire retardant (FR) garments.  From testing undertaken on a full sized manikin clothed in separate tests with a FR and non FR “coverall” demonstrated the value of FR treated materials when subjected to sparks from an angle grinder. The FR coverall did not ignite after 5 minutes of sustained spark impingement whereas the non FR coverall ignited after approximately 20 seconds and burnt to completion.

Whilst angle grinding may only occur occasionally when geo personel are on-site, ground investigations are often undertaken on operational sites where a fire or ignition hazard exists.  In such situations the selection of an approriate standard of overall is just as important.

The HSE has also looked at the vulnerability of oil contaminated fire retardant overalls in their 2011 Research Report 883. This report stated that the “study has shown that even trace amounts of oil left after washing can render an overalls’ fire protective properties moot. Contamination with hydrocarbon oils does not appear to have permanently damaged the performance of fire protective overalls, as this can be regained by additional washing. Tests performed on used fire protective overalls indicate that the majority of these still retain their flame retardant properties.” In terms of washing the report recomended that:

  • fire protective clothing should be laundered at the highest temperature recommended by the manufacturer, but shall not exceed this temperature or use more aggressive cleaning agents; and
  • Fire protective clothing should not be used beyond the manufacturers recommended number of washes.

The final recommendation was:

Do not assume that fire protective clothing will always self-extinguish and make other provision available for extinguishing flame.