Servicing & maintenance
Essential Safety and Maintenance Tips for Fume Cupboards
A fume cupboard is a piece of safety equipment before it is a piece of laboratory furniture. What follows covers how they are designed, how they should be used, what maintaining one actually involves, and the legal duties that sit behind all of it.
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A fume cupboard protects the person standing at it by drawing contaminated air away from the breathing zone and out of the building. That protection is not permanent. It depends on the enclosure being sound, the airflow being correct, the operator working in the right way, and the whole system being examined on a schedule set out in law.
This guide covers the four things a laboratory needs to get right: what the equipment is designed to do, how to use it correctly, what maintaining it involves, and where the legal duties sit.
Understanding fume cupboards
Key design and safety standards
- —Performance standard. BS EN 14175 is the standard fume cupboards are built and tested against. It covers type testing at the factory, commissioning on site, and the periodic testing that follows for the rest of the unit’s working life.
- —Face velocity. Air is drawn through the sash opening at a controlled speed — commonly around 0.5 m/s at the working height. Too slow and containment is lost; too fast and turbulence at the face can pull contaminants back out.
- —Materials. Liners, work surfaces and service fittings are specified for the chemistry they will meet. The wrong liner for the work degrades, and a degraded liner cannot be cleaned.
- —Airflow monitoring. An airflow monitor tells the operator that the cupboard is working now, not that it worked at the last annual test. It should alarm on low flow and be calibrated as part of routine service.
Placement and usage considerations
- —Location. Away from doorways, main walkways and busy benches. People passing close to the face disturb the air curtain the cupboard depends on.
- —Cross-draughts. Open windows, ceiling diffusers, air conditioning units and other extract equipment nearby can all defeat a correctly performing cupboard.
- —Make-up air. A room cannot extract more air than it is supplied with. Where extract and supply are out of balance, performance suffers regardless of the cupboard itself.
Types and features of fume cupboards
- —Ducted. Contaminated air is extracted and discharged outside the building. The most common arrangement, and the one that suits the widest range of chemistry.
- —Recirculating (ductless). Air is filtered and returned to the room. Flexible and quick to install, but the filter has to be matched to the substances in use and replaced on a monitored schedule.
- —Specialist enclosures. Perchloric acid cupboards with washdown facilities, radioisotope units, walk-in cupboards for large apparatus, and laminar flow or biosafety cabinets, which protect the work or the operator in different ways again.
Proper usage of fume cupboards
Initial setup and daily checks
- —Check the monitor. Confirm the airflow indicator is reading and not in alarm before any work begins. If it is showing a fault, the cupboard is out of use until it has been looked at.
- —Check the certificate. The examination is valid for a maximum of 14 months. An expired label means the cupboard should not be relied on.
- —Inspect the enclosure. Clear work surface, clean sash, unobstructed baffle slots and airfoil, sash moving freely and holding position.
During use
- —Work well inside the enclosure. Keep apparatus at least 150 mm behind the sash line, and raise bulky items on blocks so air can pass underneath.
- —Keep the sash low. The sash is the barrier. Use it at the marked working height, and lower it fully whenever the work allows.
- —Move slowly. Quick reaching in and out generates the turbulence that pulls contaminants past the face. So does walking briskly past an open cupboard.
- —Know the alarm response. Every user should know what to do if the airflow alarm sounds mid-procedure: make safe, lower the sash, leave the area, and report.
Post-use
- —Clear and clean down. Remove apparatus and waste, then wipe the work surface. See cleaning a fume cupboard for the full routine.
- —Close the sash and leave the extract running long enough to clear the enclosure, following your local procedure.
- —Report defects immediately. A noisy fan, a sash that drifts, a monitor reading low. Small faults reported early are cheaper than failed tests.
Maintenance guidelines
Regular inspection and testing
A thorough examination and test at intervals of no more than 14 months, carried out by a competent person, is the backbone of the regime. It covers face velocity, containment, airflow visualisation, the alarm and monitor, and the mechanical condition of the enclosure and extract system. See fume cupboard testing for what a visit includes.
Between examinations, planned servicing keeps fans, motors, drive belts, sash mechanisms, filters and monitors in the condition the test assumes.
Maintenance record keeping
- —Keep the records. COSHH requires the results of each examination and test to be kept for at least five years. In practice you want the service history alongside them.
- —Keep an asset list. Every enclosure identified, with its location, type, last test date and next due date. This is what turns compliance from a scramble into a schedule.
Cleaning and upkeep
- —Routine cleaning after each session and weekly, using a cleaner compatible with the liner and with the extract running.
- —Deep cleaning monthly, reaching corners, service fittings, the cup sink and behind the baffle where the design allows.
- —Decontamination before any intrusive work. Nobody should open up an enclosure, change a filter or remove a unit before it has been decontaminated and signed off.
Legal requirements and compliance
Compliance with COSHH and other regulations
Under the Control of Substances Hazardous to Health Regulations 2002, local exhaust ventilation must be thoroughly examined and tested at intervals of no more than 14 months by a competent person, and the results kept for at least five years.
- —The duty sits with the employer, not the contractor. Engaging a testing company does not transfer it.
- —The Health and Safety at Work etc. Act 1974 sits above COSHH, with the general duty to provide and maintain safe plant and systems of work.
- —Sector rules add to this, not replace it: GMP requirements in pharmaceutical manufacturing, CLEAPSS guidance in schools and colleges, and local rules for radioactive or biological work.
Ventilation and environmental controls
- —Discharge. Extracted air must be released where it cannot re-enter the building or affect neighbours — clear of windows, intakes and occupied areas.
- —Room balance. Extract and supply are considered together. Changes elsewhere in the building can quietly undermine a cupboard that passed last year.
Training and safety measures
- —Induction. Every user trained on the specific cupboards they will work at, including sash height, alarm response and what the monitor is telling them.
- —Refresher training, recorded, and repeated when equipment or procedures change.
- —Emergency procedures. Spill response inside the enclosure, airflow failure, and fire, written down and known before they are needed.
FAQs
BS EN 14175 is the performance standard, covering type testing, on-site commissioning and periodic testing. Alongside it, COSHH sets the legal duty to examine and test local exhaust ventilation at intervals of no more than 14 months and to keep the records.
Keep it away from doorways, walkways, windows and air conditioning outlets, so passing traffic and cross-draughts cannot disturb the air curtain at the face. The room also needs enough make-up air to replace what the cupboard extracts.
Work with the sash at its marked working height and no higher, and lower it fully whenever the task allows and whenever the cupboard is unattended. The sash is a physical barrier as well as the aperture the airflow is designed around.
A thorough examination and test at least every 14 months by a competent person, planned servicing of fans, motors, sash mechanisms, filters and monitors in between, and daily user checks of the monitor and the enclosure before work starts.
The employer. Testing can be contracted out to a competent person, but the duty to make sure the equipment is examined, maintained and recorded stays with the organisation operating the laboratory.
Consider reaching out to Holliday Technical Services and speak to one of our team today. We have specialist technicians available for fume cupboard testing, laminar flow, biosafety cabinets, and other LEV equipment. Holliday Technical Services can also offer via our sister company MTH (Holliday Fielding Hocking Ltd) access to purchasing new and refurbished equipment which can be installed in any laboratory, school, business or university in the UK. Contact us on: +44 (0)113 245 4111.