Fume cupboards are a type of local exhaust ventilation (LEV) system which are widely used in chemical laboratories as an engineering control to remove airborne contaminants. They provide protection both to the operator and others in the same workspace.
Those who are users of fume cupboards (either ducted or recirculating) are required to complete the LEV Moodle course. This provides the user with knowledge of why LEV systems are important, how they provide protection, what user checks they must undertake to ensure that they are working correctly and what action to take if they are not working.
The following points provide a brief summary of the course as it relates to fume cupboards:
1. Before use checks
All users must carry out pre use checks on the fume cupboard system to confirm that it is working as intended. Fume cupboards are fitted with an air flow meter, which may be a digital or analogue gauge, or a series of coloured lights. The meter should show an acceptable flow rate before commencing work. Records of any defects or issues should be recorded in the logbook and you should inform your department as per local procedures and display an Out of Use sign.
2. If the alarm sounds:
- the fume cupboard will no longer be providing protection;
- you must stop work, and make your experimental work safe if this can be done without risking possible exposure;
- display the "Out of Use" sign;
- inform other people working in the area and evacuate the space if necessary to prevent possible exposure;
- inform the Technical Services Manager as soon as possible.
If there has been any exposure, or even possible exposure to hazardous substances, an accident/incident form must be submitted and if required seek further medical advice.
3. Recirculating Fume Cupboards
These contain one or more filters in the housing unit. The user must check to make sure that the filters are compatible with the substances that they are using. Their safe operation relies on the filters being changed before reaching their capacity. This is often indicated on the cupboard by a gauge or different coloured lights which indicate when the flow through the filter has dropped below the acceptable level. Typically, recirculating fume cupboards take a few minutes to achieve the acceptable flow rate.
4. Maintenance and Inspection
Fume cupboards are subject to annual inspection and to a regular maintenance programme. Often these are carried out at the same time by an external contractor. The outcome of the most recent inspection and the date of the next inspection should be indicated on a sticker attached to the fume cupboard.