Standards and guidance for explosion safety

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) are the main UK workplace regulations for managing fire and explosion risks arising from dangerous substances. DSEAR requires employers and operators to identify dangerous substances, assess the likelihood of explosive atmospheres, classify hazardous areas, control ignition sources and implement suitable technical and organisational measures. In practice, DSEAR forms the legal basis for the UK equivalent of an ATEX workplace assessment. For industrial operators, it is not just a compliance document; it is the framework for proving that explosion risks are understood, controlled and managed throughout the life cycle of the installation.

HSE Approved Code of Practice L138, “Dangerous substances and explosive atmospheres”, provides authoritative practical guidance on how to comply with DSEAR. Although an ACOP is not the same as legislation, it carries significant legal weight because it describes what the Health and Safety Executive considers acceptable practice. For hazardous area classification, risk reduction, ignition source control, documentation, maintenance, training and emergency arrangements, L138 is one of the most important reference documents in the UK. From a consultancy perspective, L138 helps translate legal duties into practical, auditable and defensible safety measures.

The Health and Safety at Work etc. Act 1974 is the foundation of occupational health and safety law in Great Britain. It places a general duty on employers to protect employees and others who may be affected by the company’s activities. In the context of explosion safety, this means that the employer must provide safe plant, safe systems of work, adequate training, competent supervision and proper control of risks associated with flammable gases, vapours, mists and combustible dusts. For clients, this is a key management responsibility: explosion safety is not only a technical issue, but a board-level duty of care.

The Management of Health and Safety at Work Regulations 1999 require employers to carry out suitable and sufficient risk assessments and to organise preventive and protective measures. These regulations support DSEAR by requiring a structured safety management approach. For explosion safety, this means assigning responsibilities, ensuring competence, controlling contractors, reviewing changes, maintaining procedures and keeping risk assessments up to date. In practical consultancy work, these regulations connect the technical DSEAR assessment with the client’s management system, ensuring that explosion safety remains controlled during operation, maintenance, modification and expansion.

The Electricity at Work Regulations 1989 require electrical systems to be designed, installed, maintained and operated so as to prevent danger. In hazardous areas, electrical equipment is a potential ignition source and must therefore be suitable for the zone, gas or dust group, temperature class, environmental conditions and installation method. These regulations support the need for correct Ex equipment selection, cable gland selection, earthing, bonding, inspection and maintenance. For clients, this is particularly important because many explosion safety deficiencies are found in electrical installations, modifications, repairs and poorly documented Ex inspections.

The Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 2016 are the UK product regulations for equipment, protective systems, components and safety devices intended for use in potentially explosive atmospheres. They are broadly comparable to the EU ATEX 114 Directive 2014/34/EU. These regulations apply to products placed on the Great Britain market and cover conformity assessment, marking, technical documentation, instructions and manufacturer obligations. For operators and purchasers, this regulation is critical when selecting or modifying Ex equipment, because the correct product certification must match the actual hazardous area classification and intended use.

The BS EN / BS EN IEC 60079 series provides the main technical framework for explosive atmospheres in the UK. It covers hazardous area classification, equipment protection concepts, electrical installation design, selection, inspection, maintenance, repair and intrinsically safe systems. Typical examples include BS EN IEC 60079-10-1 for gas area classification, BS EN 60079-10-2 for dust area classification, BS EN IEC 60079-14 for electrical installation design and selection, BS EN IEC 60079-17 for inspection and maintenance, and BS EN IEC 60079-19 for repair and overhaul. For clients, this standard series provides the technical evidence needed to demonstrate that DSEAR obligations have been implemented correctly and professionally.

BS EN ISO 80079-36 and BS EN ISO 80079-37 are essential standards for non-electrical equipment used in explosive atmospheres. They apply to mechanical equipment such as mixers, rotary valves, conveyors, fans, pumps, gearboxes, bearings, couplings and process machinery. These standards require a structured ignition hazard assessment covering hot surfaces, mechanical sparks, friction, impact, electrostatic charging, compression heating, deposits and foreseeable malfunctions. For industrial clients, this is often a hidden risk area: mechanical equipment is frequently present in dust and gas zones, but the ignition source assessment is not always sufficiently documented.

BS EN 1127-1 defines the fundamental principles of explosion prevention and explosion protection. It provides a systematic method for identifying explosion hazards, assessing ignition sources and selecting preventive and protective measures. The standard supports the hierarchy of explosion safety: avoid explosive atmospheres where possible, prevent effective ignition sources, and limit the consequences of an explosion where prevention alone is not sufficient. In consultancy practice, BS EN 1127-1 is highly valuable because it connects process conditions, hazardous substances, equipment, ignition sources and protective measures into one coherent explosion safety concept.

The GOV.UK designated standards list identifies which standards give a presumption of conformity with the relevant UK product regulations, including equipment and protective systems intended for use in potentially explosive atmospheres. For manufacturers, importers, suppliers and technical assessors, it is important to verify whether the applied BS EN or BS EN IEC standard is currently designated in Great Britain. This is particularly relevant for UKCA/CE compliance, declarations of conformity, technical files and market access. For clients, checking the designated standards reduces legal uncertainty and supports a defensible procurement and compliance strategy.