Introduction

In a laboratory, a fume cupboard is one of the most common and effective items of safety equipment. It is known collectively as Local Exhaust Ventilation which is used to reduce exposure to airborne hazardous substances such as dust, mist, fume, vapour or gas in a workplace by capturing and extracting the hazardous substance at the source of the emission.

This guide applies to work tasks, including teaching activities, carried out in fume cupboards as defined below. It does not apply to biological safety cabinets for work with pathogens, laminar flow cabinets or gloveboxes.

Definitions

A fume cupboard, also known as a fume hood, fume cabinet or chemical cabinet is a type of local ventilation device that is typically a large piece of equipment enclosing five sides of a work area with a moveable sash window, the bottom of which is most commonly located at a standing work height.

They can be ducted or recirculating (ductless). For both types air is drawn in from the front (open) side of the cupboard, and either expelled outside the building (ducted) or made safe through filtration and fed back into the room (ductless).

It functions by maintaining a relatively negative pressure in the interior of the fume cupboard to prevent any contaminant from escaping while drawing air in through the hood opening at a consistent rate.

Fume cupboards shall comply with relevant safety requirements specified in EN 13150:2001, clause 5.

Face Velocity is the speed at which air is drawn into the fume cupboard. This defined as 0.5m/s for hazardous substances. (CoSHH Control Guidance Sheet 201 Fume Cabinets).

The Operational Sash Opening or the sash working height is the maximum position at which the sash should be open whilst an experiment is in operation. This should be 500 mm in the direction of sash movement and shall not exceed 600 mm (Fume Cupboards Part 2: Safety and Performance requirements BSEN14175-2:2003).

Responsibilities

1) Users should:

carry out a COSHH assessment to justify the use of a fume cupboard to control the hazard. The COSHH Assessment should identify the correct type of fume cupboard for the task
use the fume cupboard in accordance with the manufacturer’s instructions and the training provided. A fume cupboard that is operating outside safe parameters (i.e. face velocity <0.5 m/s) should not be used
use the fume cupboard only for its intended purpose

For example the following practices are not advocated unless justified by risk/COSHH assessment:

as a means of venting equipment from the laboratory area
for boiling large (> 100ml) quantities of solvents or acids, such as for waste disposal purposes
- report any defects/alarms promptly to the Area/Department Safety Co-ordinator. Make safe and take out of service. Loss of containment should be reported as an incident via the online reporting tool

2) Supervisors/Managers should:

ensure users are trained in correct safe operating procedures. This includes set-up of fume cupboard, good safe working practice and what to do in an emergency. Maintain records of training

3) Technical Services Managers should:

ensure fume cupboards are registered with Estates for statutory examination and testing as required by COSHH Regulations 2002
notify Estates when new fume cupboards are to be installed for agreement, sizing, airflow balancing and inclusion on maintenance schedule

4) Estates Management should:

maintain a record/schedule of all fume cupboards on campus
arrange for and maintain a record of all maintenance and inspections of fume cupboards. Inform Departments if remedial work is required and if a fume cupboard fails its inspection
arrange for remedial work to be carried out on fume cupboards or decommission if no longer required by the Department

Safe use of fume cupboards

This guide sets out responsibilities to ensure fume cupboards are used and maintained correctly, providing the required protection for laboratory users.