Posted By George Wedgwood A severe test of Unreasonablility and reasonableness must be undertaken before live work is commenced, as per the E@W Regs. How this is done and understood is not for the fainthearted! Few undertakings have actually cracked this test properly and those that think they have will still fail when they have a fatality! A properly thought through system of assessment must be in place with checking by competent persons who can demonstrate their ability to assess live working situations and environments. Typical environments include operational switchrooms and substations - even with metalclad gear. The assessment must concentrate on the potential effects of a short circuit fault arc and the energy release - not an easy assessment! Typical control measures are distance, screening and heavy flame retardant PPE, with full face screens and FR gloves. All of this does work but is understandably not fully accepted by industry due to cost and difficulty of application. Certainly, competence helps but most of the fatalities occur to highly competent employees! I believe we have a way to go yet and we need to be specifying arc proof gear with very stringent measures before allowing live work. The alternatives are clear - work dead and shut the board or circuit down before allowing persons near live apparatus, or design and install gear that cannot affect personel when under extreme fault conditions, even when partially exposed or open. The assessment for risks is difficult and not fully explained by the current HSE guidance. However, the Electricity Association has produced guidance for Member Companies on FR clothing against arcs. Contact me on george.wedgwood@pgen.com for further information if required - or better still, work dead under a PTW!!

Posted By Ken Taylor Essentially, a safe working method is needed based upon risk assessment. This may (and probably will) require a PTW system unless regular and essential live working is being undertaken in specifically designed environments using the correct equipment with established, taught and known safe procedures.