I was asked to prepare this summary some time ago - but it might be of interest !
20th December 2002
Electricity at Work – Safe Working Practices.
The European Standard EN50191 provides guidance on how electrical testing should be carried out in test environments. The date of implementation was 1st March 2001 and all conflicting National Standards were withdrawn on 1st October 2002. Compliance with EN50191 is a necessary requirement to show due diligence and best working practice. The Health & Safety Executive have published guidance which is not compulsory but is designed to ensure that electrical testing is done in such a way as to comply with the law. Particular reference is made to “live working” and the requirements to ensure that this is done safely.
Live working is defined as testing, calibrating or repairing equipment whilst that equipment is connected to a hazardous voltage source and the equipment is energised. The requirements are particularly relevant when the equipment is partially dismantled i.e. the protective casing is removed. Within the E.B.M.E. workshop, live working is a daily event carried out by all the Technicians.
Most of the requirements detailed in the standard can be ignored because the Technicians are classed as “competent persons” who understand the danger and the consequences of electrical shock and who already work to good workshop practice procedures. Currently each bench is supplied from a double 13 amp socket incorporating a Residual Current Device which breaks the supply if a fault current greater than 30mA is detected. However, there are a number of physical requirements within the E.B.M.E. workshop which we will have to implement in order to comply. A survey has been done by Mr Stuart Bruce of Clare Instruments Ltd and I quote his recommendations below. Although Clare offer these surveys as a means of generating sales of their protective and test equipment, his survey has not indicated the need to purchase any of their products, so can be considered as independent.
Recommendations.
“Barrier system required to stop access to test / work area, with warning signs.
Emergency stop (kill power) switch required area.
Benches require separation barriers.
Good safe working practice document required.”
The barrier system is required to clearly define the boundary between the administrative areas and the electrical test areas. This must consist of a self-closing door or similar physical barrier and have a warning notice attached forbidding entry to unauthorised personnel.
The emergency stop switch must be a push-button type and must isolate the power from the workbenches in case of emergency. The switch must be high visibility, adjacent to the benches but accessible without approaching the bench – similar to those fitted in the Estates Workshops to isolate the large pieces of fixed equipment.
Because each bench is used by two technicians, there must be a physical barrier separating the two work areas to avoid physical contact with equipment in the adjacent work area.
The safe working practice policy will be addressed within the ISO9000 manual.
The first two items will require some funding and the assistance of the Estates personnel to implement. The barriers on the benches can be readily accomplished with the help of a joiner !
Roy Flitcroft. E.B.M.E. Manager.
