Health and Safety Executive Health and Safety Executive Electrical Engineering HSE Perspective John Madden CEng FIET Principal Electrical Inspector Team Manager Scotland, Wales & West ADIPS Inspection Body Conference 2010

Agenda BS 7671 and BS 7909 Arctic cables Generators Anything else for discussion

BS 7671 and BS 7909 BS 7671 – Requirements for electrical installations –Covers requirements for LV power generation & distribution systems –Non-statutory, apart from in Building Regulations –Provides route to compliance with Electricity at Work Regs –Section 740 contains specific requirements for amusement devices etc

BS 7671 and BS 7909 BS 7909 Code of practice for temporary electrical systems for entertainment and related purposes –Non-statutory standard –Offers guidance on management and control of event electrical systems, as well as design issues –Cross references BS –Makes recommendations for inspection and testing.

BS 7671 and BS 7909 The two standards appear to be complementary. –BS 7671 provides detailed technical requirements that are treated as a benchmark technical standard –BS 7909 provides a commentary on the application of those requirements and how to manage electrical safety at events There is no duty to comply with either of these standards, but they do provide a useful and helpful route to legal compliance. Are there problems from the ADIPS perspective?

BS 7671 Section 740 The most controversial requirements appear to be: –300 mA RCD at origin. –30 mA RCD protecting lighting and socket- outlet circuits and mobile equipment connected by 32 A flex. –Inspection and testing after each assembly on site - open to interpretation, judgement required. Are these problematic?

Arctic cables Flexible cables for use at low temperatures. Main applicable standards are: –BS 7919 Electric cables. Flexible cables rated up to 450/750 V, for use with appliances and equipment intended for industrial and similar environments –BS 6500 Electric cables. Flexible cords rated up to 300/500 V, for use with appliances and equipment intended for domestic, office and similar environments

BS 7919 Table 44 The IET has advised that this cable is suitable only for 110 V applications. It is unclear why this should be the case – the standard clearly indicates suitability for 300/500 V duty and manufacturers certify their products for this voltage range. Similarly, cables to BS 6500 are rated at 300 V so are suitable for 230 V applications. Do we have a history of problems with this type of cable?

Generators A continuing cause for concern –Inappropriate o/current protection –Badly made connections –Access to live parts They are a crucial part of the electrical system and should both be safe and subjected to routine inspection by a competent person.

Generators It is my view that generators and supply cables should be part of the ADIPS inspection regime. Where possible, amusement devices should be inspected and tested with a generator connected, preferably the one that’s being used operationally. Controllers should know how to connect them safely and how to use distribution switchgear to distribute power to multiple loads.

The End ….. Any questions/comments?