Dangerous substances and explosive atmospheres

Health and Safety

Dangerous substances and explosive atmospheres Dangerous Substances and Explosive Atmospheres Regulations 2002 Approved Code of Practice and guidance This Approved Code of Practice (ACOP) and guidance provide practical advice on how to comply with the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR). These Regulations require the elimination or reduction of risk of fire and explosion from substances connected with work activities.

The ACOP is primarily for an informed and experienced audience such as health and safety professionals. It applies to workplaces that manufacture, store, process or use dangerous substances as defined in this publication.

This second edition of L138 incorporates the four previous DSEAR ACOPs on design, storage, control and safe maintenance.

The consolidated ACOP text and guidance have been simplified, streamlined, and restructured to help the reader. No significant new duties are placed on businesses L138 (Second edition) that are in compliance with the replaced ACOPs, although the content has been Published 2013 updated in light of changes to European and domestic legislation, such as substance classification and labelling and general fire safety. The Regulations themselves are unchanged.

HSE Books

© Crown copyright 2013

First published 2003 Second edition 2013

ISBN 978 0 7176 6616 4

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Approved Code of Practice

This Code has been approved by the Health and Safety Executive, with the consent of the Secretary of State. It gives practical advice on how to comply with the law. If you follow the advice you will be doing enough to comply with the law in respect of those specific matters on which the Code gives advice. You may use alternative methods to those set out in the Code in order to comply with the law.

However, the Code has a special legal status. If you are prosecuted for breach of health and safety law, and it is proved that you did not follow the relevant provisions of the Code, you will need to show that you have complied with the law in some other way or a Court will find you at fault.

Guidance

This guidance is issued by the Health and Safety Executive. Following the guidance is not compulsory, unless specifically stated, and you are free to take other action. But if you do follow the guidance you will normally be doing enough to comply with the law. Health and safety inspectors seek to secure compliance with the law and may refer to this guidance.

Contents

Introduction 9 About this book 9 About ACOPs 10 Presentation of regulation, guidance and ACOP text 10 About DSEAR 10 Scope of ‘employer’ 10 Information for use in risk assessment 10 The legislative background 11 DSEAR and other legislation on dangerous substances or hazardous activities 11 Consulting employees and safety representatives 13 The Regulations 14 Regulation 1 Citation and commencement 14 Regulation 2 Interpretation 14 Key terms explained 17 Approved classification and labelling 17 Explosive atmospheres 17 Hazard 18 Other events 18 Physico-chemical or chemical property 18 Safety data sheets 19 Workplace 19 Work processes 19 Technical supervision measures 19 Regulation 3 Application 20 Maritime activities 21 Exclusions from regulations 5(4)(c), 7 and 11 21 Areas used directly for and during the medical treatment of patients 21 The use of gas appliances burning gaseous fuels 22 Gas fittings 22 The manufacture, handling, use, storage and transport of explosives or chemically unstable substances 22 Mineral extracting industries 23 Use of means of transport 23

Regulation 4 Duties under these Regulations 24 Regulation 5 Risk assessment 25 Risk assessment 26 The hazardous properties of a substance 28 Information on hazardous properties 29 Circumstances of the work 30 Risk assessment of non-routine maintenance and related higher-risk activities 31 Cleaning 33 The effect of measures already in place or which will be taken as a result of DSEAR 33 The likely presence and persistence of explosive atmospheres, and the need for hazardous area classification 34 Consideration of ignition sources 35 Scale of the anticipated effects and extent of harm 37 The need to consider places connected via openings to places in which explosive atmospheres may occur 37 Additional information for the risk assessment 37 Reviewing and revising the risk assessment 38 Recording the significant findings of the risk assessment 39 Information to be recorded when an explosive atmosphere may occur 40 Records concerning co-ordination 41 Risk assessment of new work activity 41 Regulation 6 Elimination or reduction of risks from dangerous substances 42 Overall approach 43 Substitution 43 Control and mitigation measures 43 Reduce the amount of dangerous substance to a minimum 44 Storage of flammable liquids in process areas, workrooms, laboratories and similar working areas 44 Storage and use of compressed and liquefied flammable gas cylinders, oxygen and oxidising gas cylinders in process areas, workrooms, laboratories etc 46 Design of plant and equipment to minimise release of dangerous substances 47 Ventilation 49 Ventilation: First choice – natural dispersion 50 Ventilation: Second choice – indoors and ventilated from open air 50

Ventilation: Third choice – mechanical ventilation 51 Ventilation: Fourth and last choice – extraction ventilation to the entire workspace 52 Ventilation of plant and machinery 52 Adequate ventilation 52 Temporary exhaust ventilation systems 53 Containment and collection of spillages and leaks 53 Control and avoidance of ignition sources including electrostatic discharges 53 Segregation of incompatible dangerous substances 56 Mitigation – avoiding propagation 57 Physical barriers of fire-resisting construction – design and performance requirements 58 Measures to mitigate the effects of an explosion (including explosion relief, suppression and pressure-resistant plant) 61 Transport of dangerous substances on site 62 Waste containing dangerous substances 63 Security 63 Review of control and mitigation measures 63 Residual risk 63 Schedule 1 General safety measures 64 Design considerations 65 Deliberate combustion of dangerous substances 65 Safe systems of work 66 Dangerous substances used as cleaning agents 66 Systems of work 67 Operating procedures (low-risk activities) 67 Safety method statements (medium-risk activities) 67 Permit-to-work systems (high-risk activities) 68 Hot work 69 Preparation and procedures for hot work 70 Cleaning and gas-freeing plant for hot work 70 Inerting 71 Using gas welding and cutting equipment 71 Redundant plant and equipment 72 Disposal of static vessels containing compressed and liquefied flammable gases 73 Disposal of underground petrol storage tanks 73 Regulation 7 Places where explosive atmospheres may occur 73 Schedule 2 Classification of places where explosive atmospheres may occur 74

Schedule 3 Criteria for the selection of equipment and protective systems 75 Schedule 4 Warning sign for places where explosive atmospheres may occur 76 Hazardous area classification 76 Selection of equipment for use in hazardous areas 78 Marking areas containing explosive atmospheres 81 Verification of places containing explosive atmospheres 82 Provision of antistatic clothing and footwear 83 Regulation 8 Arrangements to deal with accidents, incidents and emergencies 84 Regulation 9 Information, instruction and training 91 Regulation 10 Identification of hazardous contents of containers and pipes 93 Schedule 5 Legislation concerned with the marking of containers and pipes 94 Regulation 11 Duty of co-ordination 95 Regulation 12 Extension outside Great Britain 95 Regulation 13 Exemption certificates 96 Regulation 14 Exemptions for Ministry of Defence etc 96 Regulation 15 Amendments 97 Schedule 6 Amendments 97 Regulation 16 Repeals and revocations 97 Schedule 7 Repeals and revocations 97 Regulation 17 Transitional provisions 99 Appendix 1 Notice of Approval 100 Appendix 2 Other relevant legislation 101 Relationship with other health and safety legislation 101 The Management of Health and Safety at Work Regulations 1999 101 The Control of Substances Hazardous to Health Regulations 2002 101 Classification, labelling and packaging of dangerous substances 101 Registration, Evaluation, Authorisation and Restriction of Chemicals EC no 1907/2006 (REACH) 102 The Provision and Use of Work Equipment Regulations 1998 102 The Personal Protective Equipment Regulations 1992 102 The Petroleum (Consolidation) Act 1928 and associated regulations 102

Appendix 3 Revocation of CHIP and the application of the European CLP Regulation 103 Implications for DSEAR 103 What does this mean for chemical users? 103 Withdrawal of the HSE Approved Supply List 104 Guidance on the CLP Regulation 105 Appendix 4 Fire resistance 106 Appendix 5 Fire reaction 107 Appendix 6 Workplace and work equipment transitional provisions under regulation 17 108 Reference and further reading 110 Glossary 116 Further information 119

Introduction

About this book

1 The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) Approved Code of Practice (ACOP) text and associated guidance provide practical advice on how you can comply with the requirements of the Regulations.

2 The ACOP is intended primarily for an informed and experienced audience such as professional health and safety staff and those who may give advice to smaller businesses rather than the small businesses themselves. The leaflet INDG3701 provides a short guide to DSEAR and is aimed at small and medium- sized businesses. Information on DSEAR can also be accessed via the Fire and explosion pages of HSE’s website at www.hse.gov.uk/fireandexplosion.

3 This publication is for places of work that manufacture, store, process or use dangerous substances as defined in paragraph 33. It contains an ACOP explaining what is required for compliance, together with guidance on the duties in DSEAR. It has been prepared by the Health and Safety Executive (HSE) after consultation with stakeholders in industry, trades unions, local authorities and fire authorities. While Unloading petrol from road tankers2 continues as a separate ACOP, four DSEAR ACOP publications from 2003 have been merged into the original main ACOP L138 Dangerous Substances and Explosive Atmospheres namely:

(a) L134 Design of plant, equipment and workplaces; (b) L135 Storage of dangerous substances; (c) L136 Control and mitigation measures; (d) L137 Safe maintenance, repair and cleaning procedures.

4 The ACOP text and guidance have been simplified, streamlined and any previous ambiguities removed. The changes, which are summarised below, have been widely consulted on.

5 Changes in this edition include:

(a) some guidance has been assigned ACOP status and vice versa. For example, previously no ACOP material existed for regulations 7 and 10. However, these changes were introduced to provide clarification on how to comply and do not introduce any new requirements; (b) adjustments in light of European and other legislation that has or will be introduced after DSEAR came into force such as: (i) general fire safety legislation (see paragraph 20); (ii) classification for labelling and packaging (see Appendix 3); (c) clarification on the scope of the Regulations in relation to incompatible substances being outside the scope of DSEAR but within the scope of the Health and Safety at Work etc Act (the HSW Act) (see paragraph 255); (d) Schedules to the Regulations have been moved from the end of the document to sit near their respective regulation; (e) the list of references and further reading has been updated.

About ACOPs

6 Approved Codes of Practice are approved by the HSE Board with the consent of the Secretary of State (see Appendix 1: Notice of Approval for details).

7 The ACOP describes preferred or recommended methods that can be used (or standards to be met) to comply with the Regulations and the duties imposed by the HSW Act. The accompanying guidance also provides advice on achieving compliance, or it may give information of a general nature, including explanation of the requirements of the law, more specific technical information or references to further sources of information.

8 The legal status of ACOP and guidance text is given on the copyright page.

Presentation of regulation, guidance and ACOP text

9 The ACOP text is set out in bold and the accompanying guidance in normal type, the text of the Regulations is in italics. Coloured borders also indicate each section clearly. Each regulation is preceded by a short summary of the main duties imposed by that regulation and aims to help the reader navigate the document. This summary text is for information only.

About DSEAR

10 The Dangerous Substances and Explosive Atmospheres Regulations 2002 (SI 2002/2776) set minimum requirements for the protection of workers from fire and explosion risks related to dangerous substances and potentially explosive atmospheres. The Regulations apply to employers and the self-employed at most workplaces in Great Britain where a dangerous substance is present or could be present.

11 DSEAR revoked or modified a large amount of old legislation relating to flammable substances and dusts including the Highly Flammable Liquids and Liquefied Petroleum Gases Regulations 1972 (SI 1972/917) and section 31 of the Factories Act 1961. Safety standards were maintained through a combination of the requirements of DSEAR and ACOPs reflecting practices in the preceding legislation.

Scope of ‘employer’

12 The term ‘employer’ is used throughout the document and should be understood to include the self-employed as a consequence of regulation 4(2). Less frequently the less-specific term ‘dutyholder’ may also be used which includes both.

Information for use in risk assessment

13 A key part of compliance with DSEAR is the risk assessment and an important principle is to separate storage areas from process areas where the two occur on the same or shared premises. Employers will find generic information on the storage of dangerous substances in other HSE and non-HSE guidance. In contrast process activities are, by their nature, very variable, and the employer should consider these in much more detail and apply the principles of risk assessment themselves as there may be less guidance available.

14 Health effects from substances and preparations are not within the scope of DSEAR and are covered by legislation such as the Control of Substances Hazardous to Health Regulations 2002 (SI 2002/2677) (COSHH).

The legislative background

15 DSEAR 2002 was made under the Health and Safety at Work etc Act 1974 (the HSW Act). The Regulations apply to workplaces in Great Britain. The Regulations implement two European Directives:

(a) the safety aspects of the Chemical Agents Directive 98/24/EC (CAD); and (b) the Explosive Atmospheres Directive 99/92/EC (ATEX).

16 The primary purpose of DSEAR is to protect workers and others who may be at risk from dangerous substances that can cause a fire, explosion or similar energy-releasing event, such as a runaway exothermic reaction.

DSEAR and other legislation on dangerous substances or hazardous activities 17 Subject to regulation 3(1), risks from dangerous substances or explosive atmospheres may also be subject to other specific legislation dealing with, for example:

(a) risks from major hazard activities, covered by the Control of Major Accident Hazards Regulations 1999 (SI 1999/743) (COMAH); (b) the prevention of fires and explosions offshore through the Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995 (SI 1995/743) (PFEER) or the Offshore Installations and Pipeline Works (Management and Administration) Regulations 1995 (SI 1995/738); and (c) the transport of dangerous goods, covered by specific carriage legislation, such as the Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations 2007 (CDG). (These have been superseded by the Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations 2009 (SI 2009/1348). Reference to the amendment has yet to be reflected formally in DSEAR but section 17(2)(a) of the Interpretation Act 1978 means that reference to the earlier Regulations includes the later Regulations.)

18 The above list is not exclusive and other legislation includes provisions on preventing fires and explosions for example in quarries, mines and harbour areas. In many cases, compliance with the specific requirements of such other legislation will go a long way towards meeting the requirements of DSEAR.

Relationship with other health and safety legislation 19 The duties in DSEAR apply alongside the HSW Act, other regulations made under the Act, and legislation on fire precautions and within a wider legislative context. See Appendix 2 for more information. Certain significant regulations are highlighted below.

General fire safety legislation 20 General fire safety requirements in the workplace in England and Wales are applied through the Regulatory Reform (Fire Safety) Order 2005 (SI 2005/1541). The Scottish equivalents are the Fire (Scotland) Act 2005 (2005 (asp 5)) and the Fire Safety (Scotland) Regulations 2006 (SSI 2006/456). The legislation consolidated and revoked legislation that previously covered general fire safety, including the requirement for fire certification. Current legislation requires the employer to carry out a risk assessment to determine the general fire safety requirements for their workplace and implement those requirements, including maintaining a general fire safety management plan.

21 General fire safety legislation is normally enforced by the local fire and rescue authority or in Scotland, the Scottish Fire and Rescue Service. However, there are other enforcing authorities for certain specific workplaces/worksites. HSE is the enforcing authority for general fire safety in shipbuilding and on most construction sites. At the time of publication, HSE – via the Office for Nuclear Regulation (ONR) – is the enforcing authority for fire safety in licensed nuclear premises.

22 Any general fire safety provision which could be imposed by regulations 1–6, 8, 9 and 11 of DSEAR is covered instead under this general fire safety legislation, with enforcement responsibility falling to the relevant authority, depending on the activity at the premises.

The Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 1996 23 The Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 1996 (SI 1996/192) (EPS) implement Directive 94/9/EC (the ATEX Product Directive). EPS applies to both electrical and mechanical equipment and protective systems intended for use in potentially explosive atmospheres.

24 New equipment etc supplied for use in places where an explosive atmosphere may occur must meet the requirements of EPS whatever its source. Second-hand equipment and equipment already on the shelf (for example, as spares) brought into use after 1 July 2003 also has to meet the requirements of EPS.

25 Regulation 7(6) of DSEAR made provisions in regulation 17 for transitional delays