The safe isolation of plant and equipment (HSG253) - Health and ...

More documents

Recommendations

Info

Health and Safety Executive 126 Contingency plans for planned isolation activities should include any necessary additional measures beyond your standard emergency arrangements for loss-of- containment incidents. You should ensure that any loss of containment can be: ■ identified rapidly – by personnel, gas detectors, alarm and monitor systems etc; ■ stopped rapidly – eg by identifying upstream valves for securing isolation, in particular valves which may be remotely operated; 15 and ■ contained – eg by kerbs, bunds, temporary bunds with sandbags etc. 127 Your contingency plans should also include arrangements: ■ ■ ■ to allow the work party to escape safely in an emergency; to move people away from the potential hazard (arrangements for evacuation, mustering etc); and to communicate necessary action to other parties – eg shutdown of adjacent plants. Risk assessment of variations 128 If you cannot meet the baseline isolation standard (or your established company isolation standard, as described in paragraph 107), and it is not reasonably practicable to extend the isolation envelope or defer to shutdown, follow the pathway in the grey box in Figure 5 to establish whether you may use a ‘variation’ (ie whether, based on risk assessment, it is acceptable to use a lower standard of isolation). 129 You should have a risk assessment and authorisation process to consider any proposed ‘variations’ and associated risk-reduction measures. People authorised to approve such variations should: ■ ■ ■ be of an appropriate seniority within your organisation; have the technical competence to review the risk assessment (for example equivalent to the ‘technical authority’ who set the company standard); and have operational independence from those proposing the isolation scheme. 130 Use of a variation from the baseline/established company standard of isolation should be clearly indicated and explained on your documentation (eg isolation certificate) and signed by the person authorising use of the variation. Variations due to layout or condition of plant 131 The layout or condition of your plant may restrict your ability to safely install or use baseline isolation standards. Plant modification should be considered in these circumstances (see paragraphs 137-140). Variations from positive isolation requirements for short-duration work 132 The time needed to install and remove a positive isolation can be substantial. For some short-duration work this exceeds the time to carry out the intrusive work and the main loss-of-containment risk may be associated with the installation and removal of the isolation. 133 A ‘variation’ for short-duration work can be used only where the overall risk of undertaking the activity using positive isolation (including the risks associated with installing and removing the isolation) is greater than the overall risk if a less secure isolation method is used for the intrusive work. 134 Short-duration variations are most commonly used for the removal of instruments for repair or testing, and the changing of, for example, filter elements or control valves. The safe isolation of plant and equipment Page 28 of 81
Figure 5 Flowchart for selection of ALARP isolation method Health and Safety Executive The safe isolation of plant and equipment Page 29 of 81
Page 1 and 2: The safe isolation of plant and equ
Page 3 and 4: Contents Foreword 4 Introduction 5
Page 5 and 6: Introduction Scope and target audie
Page 7 and 8: Overview of isolation hazards Healt
Page 9 and 10: Health and Safety Executive 30 The
Page 11 and 12: 43 Human failures can be grouped in
Page 13 and 14: Figure 1 Responsibilities of key pe
Page 17 and 18: Setting performance indicators for
Page 19 and 20: Health and Safety Executive 82 In a
Page 21 and 22: Health and Safety Executive Key sta
Page 23 and 24: Health and Safety Executive Hazards
Page 25 and 26: Health and Safety Executive 110 Sec
Page 27: Health and Safety Executive 120 As
Page 31 and 32: Health and Safety Executive for ret
Page 33 and 34: Level of security Methods Typical a
Page 37 and 38: Health and Safety Executive 173 Imm
Page 39 and 40: Health and Safety Executive 187 Use
Page 41 and 42: Health and Safety Executive An exam
Page 43 and 44: Health and Safety Executive Offshor
Page 45 and 46: Hazards associated with electrical
Page 47 and 48: Isolation scheme examined: Date: Ap
Page 49 and 50: 3 PLANNING and IMPLEMENTING Risk as
Page 51 and 52: Valve type Sealing ability Ball Goo
Page 53 and 54: Technique Brief description Primary
Page 55 and 56: Technique Brief description Special
Page 57 and 58: Technique Brief description Special
Page 59 and 60: Substance Pressure Appendix 6: Exam
Page 61 and 62: Health and Safety Executive 8 For m
Page 63 and 64: Release factor Health and Safety Ex
Page 65 and 66: Summary of considerations when usin
Page 67 and 68: Health and Safety Executive A secti
Page 69 and 70: valving to provide double block and
Page 71 and 72: Health and Safety Executive 19 You
Page 73 and 74: Venting or flaring activities Healt
Page 75 and 76: Appendix 9: Isolations for instrume
Page 77 and 78: Health and Safety Executive Referen
Page 79 and 80:
Glossary Health and Safety Executiv
Page 81:
Further information Health and Safe
show all

The safe isolation of plant and equipment (HSG253) - Health and ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?