Posted By Tony McBreen Asbestos and Electrical Switchgear Can someone please offer advice on the following – I look after the H&S for the Estates Department on a heavy engineering site covering 44,000 sq/mtrs. A large proportion of the low voltage network dates back to the 1960’s with the distribution being fed by 10 off 11kV sub stations. The insulator/arc protection material within many of the fuse/switches is asbestos based, MDHS 100 lists this as ‘Millboard’ with a content of 37 – 97% asbastos, with a matrix of clay and starch. The ease of fibre release is high as the material is of low density and easy to break. We had an asbestos survey carried out in 2003 but electrical distribution was not included. There have been occasions where phase protectors have been damaged and we have had no option but to replace the switch/panel. To carry out this exercise across the site would cost somewhere in the region of £250,000, this is not viable for the business. Our electrical engineer is unable to substitute the ACM with another material as it may invalidate the type testing carried out on the equipment by the OEM. Question 1 Specific to electrical switchgear, what do we need to do to comply with the CAWR 2002 (we do comply in all other areas and this is well managed) Question 2 Is there a material that will substitute the ACM used for the flash guards/arrestors/insulators that has been proven in testing on equipment of this age and will not compromise the electrical integrity of the equipment. Thank you for taking the time to consider this issue Tony McBreen

Posted By George Wedgwood Good response and I agree. I am familiar with distribution network and power station switchgear where exactly the same challenges are faced. Properly managed and labelled up, keeping an inventory, risk generic assessment and all technical details will be very important in justifying the risks of potentially poorly managed exposure, as will the detailed training of a staff involved in maintenance or operation, where access to the arc chutes etc. are made or forseen where they might be made (in emergency arc explosion for example or a fire). Also important, is the need to ensure that at least generic work instructions are carefully prepared for each maintenance operation to ensure the right advice is given, and covers the specific apparatus. Any gear that is down for complete overhaul should be pre-specified for replacement of the ACM. Regards, George

Posted By Tony McBreen Many thanks for your help gentlemen, just what I needed and am now making progress Regards Tony