Electrical Safety in the Food Industry

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1 Health and and Safety Executive Electrical Safety in the Food Industry John Chamberlain HM Principal Specialist Inspector (Electrical & Control Systems) Manchester CROWN COPYRIGHT

2 What I ll cover Legal framework Safe isolation Live working Compliance assessment Conclusions

3 How many incidents? In a typical year there are about fatal electrical accidents at work: this accounts for about 6% of work related deaths. About 60% of the deaths are from contact with overhead lines. There are up to 3000 serious reportable incidents per year as a result of injuries from electric shock, electric burns, flashovers, electrical fires and explosions.

4 Electrical fatalities electrocutions live working, OHLs, plumber etc 3 - machinery controls 1 - fire of electrical origin (work place) 2 - copper theft (could be more not all investigated/reported) 1 elimination of electrical causes

5 The legal framework Electricity at Work Regulations 1989 Systems to be safe 4(1) Duty to maintain where necessary to prevent danger - 4(2) Safe systems of work - 4(3) (see HSG85) Environment - 6 Live work/testing - 14 Competence - 16

6 Systems of work problem areas Poor management of electrical systems Lack of control energising circuits testing, request to energise cert Routinely working live with no justification Insecure isolation switched-off or taped circuit breakers etc Non-provision of locks, Notices etc Poorly written MSs, RAs and SSWs

7 Safe isolation Aimed at competent electricians working on electrical systems Should follow accepted practice.. more later isolate means disconnect and take measures to prevent inadvertent reconnection Isolation of electrical circuits usually incorporates A device that prevents energising circuit during work and a unique lock (or other equally affective means) Caution Notices warning equipment should not be interfered with No excuse for poor isolation

8 Safe isolation Person carrying out work should have secure control of the isolation Identification of circuits Locking off Proving dead Use of MCB locks Inexpensive Secure Connect circuits when completed, not before.

9 How can safe isolation be achieved? Using locking-off devices (eg locks multi-hasps & cb attachments) Safe retention of fuses, links & keys (eg lockout box, key chest) Securely disconnect, insulate & label cable tails Post caution notices at point of isolation warning equipment should not be interfered with Locking enclosures or rooms where isolation is performed is only acceptable in certain circumstances No excuse for poor isolation enforcement territory

10 Safe isolation?

11 An improvement but what s missing?

12 Safe isolation?

13 More bad practice Prohibition Notice served. Note the Isobar switches. Widely misunderstood to be isolators Not to be used as point of isolation

14 From bad to good

15 What you should see Unique locks applied to means of isolation and keys held securely or; Wiring tail removed from distribution board, insulated and coiled-up or; Fuse locking devices and safe fuse retention. Caution Notices at points of isolation Each electrician at work on an isolated circuit should have a means of isolation for the circuit GS38 voltage test equipmentavailable to prove dead at point of work Lockable enclosures only acceptable in certain circumstances

16 Examples of safety equipment

17 Safe isolation.. guidance HSE worked with industry to produce targeted guidance to establish benchmark standards. ECA/ESC/BEAMA/IET/SEL ECT published a best practice guide in April Revised 2008 NICEIC inspectors now check for locking off equipment etc.

18 Typical system fault levels This is the maximum amount of electrical energy that can be delivered during a short circuit. 400 V - 30 MVA (30,000 kw) 6600 V MVA 11000V MVA Knowledge of fault levels essential for selection of equipment. High fault levels able to vaporise metal.

19 Electrician suffered serious burn injuries due to mistakenly working live

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21 Live working 8 weeks later Not sunglasses

22 Live working Regulation 14 EaWR 1989 Reg 14 requires justification for live working and includes: Any work activity ON or NEAR live conductors where DANGER may arise Work & testing are the same! Live working permitted only under exceptional circumstances Must be fully justified Why can't the work be done dead?

23 Live working justification Is it unreasonable for the work to be done dead? YES Identify and assess the risks and methods for controlling them NO Dead working is necessary NO YES Is it reasonable for personnel to work on or near the live equipment? YES Can suitable precautions (including suitable protective equipment) be taken to prevent injury? YES Live working permitted

24 Live working Regulation 14 Suitable precautions to prevent injury include: Appropriate tools Work procedures Insulating screens/mats Isolated electrical supplies Test equipment GS38 fused test leads Control of work area Persons must be COMPETENT First aid training ASSESSMENT OF PRECAUTIONS TAKEN FOR LIVE WORKING IS A SPECIALIST ISSUE & TECHNICAL SUPPORT STAFF SHOULD ALWAYS BE CONSULTED

25 Example of precautions to take

26 GS 38 voltage testers?

27 Proximity type detectors have their place in some strip-out applications as part of an SSW

28 Would you work live on this board?

29 If so. this could happen

30 Serious burn injuries working live Klippon wiring on live side Loose connection shorted when fault finding No shrouds on live side Upstream ACB settings adjusted No SSWs etc 130K fine + 30K costs

31 Exposed 400 volt busbars If live working is allowed and can be justified then Duty Holders should survey existing equipment and make it safe eg shroud busbars

32 EAWR 14 Live working Remember. You need to satisfy all three conditions below: Does it need to be live? Do you need to be near it? Have you taken precuations? Regulation 14 is absolute. If you cannot answer yes to all three questions there is a potential breach

33 And don t forget maintenance.. Food production machine cleaned each evening by pressure washer. Machine operator suffered electric shock. Open circuit CPC with water ingress allowed exposed metal to become live. Equipment not maintained in a safe condition EAW4(2) What could/should have been done?

34 Compliance assessment: What HSE inspectors look for How is the electrical system managed? Are there any Safety Rules; are they adequate isolation..energising circuits..live testing. How are the Safety Rules controlled, and by whom? Who is authorised to do what on the system. How is competence managed? Are system/network diagrams available? Requirements for RAs and Method Statements What maintenance is done? What auditing is done!!!!!.

35 A few issues on managing electrical safety Devise & implement safety rules for work on electrical systems. Topics to include should be: Safe isolation procedures. Safety during live testing activities. Requirements for risk assessments and method statements... isolation... live working Levels of competence required, means of achieving and maintaining it. Authorising of personnel. Control of contractors. Auditing

36 A few issues on managing electrical safety continued Tool box talks on isolation and live working, RAs and MSs Policy on GS38 voltage testers Inspection and test requirements ppm Auditing Who manages and controls the electrical system?

37 Safety rules - summary Ensure safety rules are agreed jointly between workers and management. Keep them simple. Train people on their use. Ensure equipment provided for compliance. Audit regularly. Ensure breaches are seen to be acted on. Review regularly it should be a live document

38 Safety Rules quotes 18 yrs on Live working: an activity other than live testing Live work is not permitted for APs who have any medical conditions that cause dizziness, lack of co-ordination or loss of balance a simple task such as tightening a recessed terminal or changing a plugin relay, plc card or fuse.. can be done live if rest of equipment is protected.

39 Safety Rules quotes 18 yrs on For anything above a simple task then a permit to work is to be issued.. Cables of 4 mm 2 and above must not be cut live. Only competent fully trained persons can work live...but nobody assessed their competence!

40 Systems of work - guidance HSG85 offers practical advice on safe systems of work. Following it will assist compliance with EAW 4(3), 13 & 14 etc See also Electrical Safety Council publication on safe isolation (free download)

41 What happens if non-compliant? Range of sanctions: Verbal or written advice; Improvement Notice; Prohibition Notice; Prosecution of company, directors or individuals. Actual action depends upon a range of factors: severity, previous history, attitude of employer, public interest etc.

42 Further information HSE and other organisations publish guidance to indicate good practice that can help in achieving compliance with legal requirements Examples of HSE guidance: HSR25: Memorandum of guidance on EAWR HSG85: Electricity at Work, Safe Working Practices HSG230: Keeping Electrical Switchgear Safe GS38: Electrical test equipment for use by electricians See Examples of other guidance: BS7671 Requirements for Electrical Installations and associated Guidance Notes

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44 ..ANY QUESTIONS? Interested in electrical safety? Visit: HSE Info line