Combustible dust is one of the most underestimated industrial hazards in UK facilities. Grain handling, flour milling, pharmaceutical production, food processing, woodworking and metalworking all generate settled combustible dust that — if disturbed and ignited — can cause explosions capable of destroying buildings. The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) require employers to identify, assess and control combustible dust risks. The 2027 regulatory updates strengthen HSE enforcement scope and expand the duty to demonstrate that dust control systems are adequate for the zone classification.
This article explains the DSEAR framework, how ATEX zone classification works, what the 2027 changes mean for industrial facilities, and what equipment must be used in each zone.
What DSEAR requires
DSEAR implements the European ATEX workplace directive (1999/92/EC) in UK law. It applies to any workplace where dangerous substances — including combustible dusts — are present. The core requirements are:
- Hazardous area classification — identify which areas of the workplace could have an explosive atmosphere present, and classify them into ATEX zones based on the likelihood and duration of the explosive atmosphere
- Risk assessment — assess the risk from explosive atmospheres and put in place measures to eliminate or control that risk
- Equipment selection — use only equipment that is certified for the zone in which it will be used. Standard industrial equipment — including M-Class and H-Class vacuum cleaners — must not be used in ATEX zoned areas
- Documentation — produce and maintain an Explosion Protection Document (EPD) that records the hazardous area classification, the risk assessment and the control measures in place
ATEX zone classification for combustible dust
Combustible dust environments are classified into three zones based on how frequently an explosive atmosphere may be present:
- Zone 20 — a place where an explosive atmosphere in the form of a cloud of flammable dust in air is present continuously, or for long periods, or frequently. The inside of dust-handling equipment — mills, silos, conveyor housings — during operation. Equipment in Zone 20 must be ATEX Category 1D certified.
- Zone 21 — a place where an explosive atmosphere in the form of a cloud of flammable dust in air is likely to occur occasionally during normal operations. The immediate area around filling and emptying points, the inside of equipment where dust clouds form. Equipment in Zone 21 must be ATEX Category 2D certified.
- Zone 22 — a place where an explosive atmosphere in the form of a cloud of flammable dust in air is not likely to occur during normal operations but, if it does occur, will persist for only a short period. The general area around Zone 20 and Zone 21 — including cleaning areas, storage rooms and general production floor areas in facilities handling combustible dust. Equipment in Zone 22 must be ATEX Category 3D certified.
Zone 22 is the most common classification for the areas where industrial vacuum cleaners are used. A standard M-Class or H-Class vacuum cleaner — however high its filtration rating — is not ATEX certified and must not be used in Zone 22. Using uncertified equipment in a zoned area is a breach of DSEAR and creates an uninsured explosion risk.
The dust explosion pentagon
A dust explosion requires five elements: fuel (the combustible dust), oxygen, dispersion, confinement and an ignition source. DSEAR controls ignition sources in zoned areas — ATEX certified equipment is designed to eliminate or contain sources of ignition including static discharge, electrical sparks and hot surfaces. This is why standard vacuum cleaners — with unshielded motors and non-antistatic components — must not be used in classified areas regardless of their filtration rating.
What the 2027 DSEAR updates mean
The 2027 regulatory updates do not replace DSEAR — they strengthen its enforcement and expand the circumstances in which HSE will require evidence of compliance:
- Expanded enforcement scope — HSE is increasing inspection activity in sectors with known combustible dust hazards including food processing, grain handling, pharmaceutical production and woodworking. Employers who cannot produce an up-to-date Explosion Protection Document and evidence of zone-appropriate equipment will face enforcement notices
- Equipment documentation requirements — the 2027 updates strengthen the requirement to document not only what equipment is in use but why it is appropriate for the zone classification. ATEX certification certificates, equipment inspection records and operator training records all form part of the compliance evidence trail
- New sectors in scope — HSE is updating its combustible dust guidance to reflect dust explosion risks in biomass handling and battery production, creating ATEX classification questions in facilities that may not have previously considered combustible dust as a primary risk
Zone 22 equipment — V-TUF ATX range
The V-TUF ATX range is Zone 22 M-Class certified — independently tested for use in environments where combustible dust may be present in abnormal conditions:
- V-TUF ATX2000 — 45L compact stainless, 1100W, Zone 22 certified, 240V and 110V. £3,399.99
- V-TUF ATX4500i — 45L with detachable bin and automatic filter cleaning, 1100W, Zone 22 certified, 240V and 110V. £4,999.99
Both machines must be used with antistatic dust bags and antistatic hose assemblies — required accessories that form part of the Zone 22 certification.
- ATEX Zone 22 dust extractors →
- Combustible dust regulations 2027 →
- COSHH Regulations 2002 →
- Manufacturing sector hub →
- Full legislation hub →
Telephone: 01522 787978 for ATEX specification advice. Contact the V-TUF trade team →
