Health and Safety Executive/Local Authorities Enforcement Liaison Committee (HELA)

Ultra-violet radiation exposure from general workplace light sources

To: Health and Safety Enforcing Authorities

For the attention of: Local Authority Health and Safety Enforcement Managers, Health and Safety Regulators and others

This circular gives advice to local authority enforcement officers

Description: Information on ultra-violet light emissions from certain types of bulbs used for general workplace illumination (tungsten halogen lamps and compact fluorescent lights) and levels of ultra-violet radiation (UVR) exposure from their use.

Summary

This LAC includes information on:

• ultra-violet (UV) light emissions from certain types of bulbs used for general workplace illumination – tungsten halogen lamps and compact fluorescent lights (CFLs) also known as low-energy light bulbs;
• the levels of ultra-violet radiation (UVR) exposure from the use of unfiltered tungsten halogen lamps and CFLs.

LAC60/8 Appendix 1 [36KB] describes the possible hazards presented by tungsten halogen light sources when used under certain conditions. LAC60/8 Appendix 2 [60KB] describes the possible hazards presented CFLs when used under certain conditions

Version 2 provides additional information regarding tungsten halogen, deals with some presentational issues in the appendices, and in Appendix 2 clarifies the guideline levels. 

Purpose

This LAC is intended to make visiting staff aware of the potential for common workplace light bulbs to give off UVR. In some circumstances the use of these light bulbs could give rise to workers receiving a dose of UVR in excess of established international guidelines.

Background

Previous studies by the National Radiological Protection Board, NRPB, on desktop lighting systems using unfiltered tungsten halogen bulbs indicated that under certain exposure conditions, some systems may emit unacceptably high levels of UVR. Further recent research indicates that compact fluorescent lights (CFLs) also known as low-energy light bulbs present the same issue.

These lamps, which are highly efficient light sources, are becoming increasingly used at work. In 1993 HSE supported a 6-month study by NRPB to identify the extent and magnitude of any potential problem that tungsten halogen bulbs create. The study, conducted by questionnaire, was a snapshot survey to ascertain the use of tungsten halogen light sources in workplaces. The questionnaire was designed to provide information on the numbers, types and applications of tungsten halogen lamps in a statistically selected sample of commercial, service and industrial organisations. In addition, it considered the extent to which filtration is incorporated in the lamps as well as length of time used and distance from personnel.

After this research the NRPB merged into the Health Protection Agency (HPA). In 2008 the HPA conducted similar research looking at CFLs. This research was principally laboratory based and was focused on measuring the actual UV emissions from the bulbs at various distances. The emissions were then compared to the internationally agreed UV exposure guidelines.

Advice

It is generally recommended that all tungsten halogen lamps and CFLs should either be fitted with an appropriate UVR filter, or a bulb with a glass outer envelope (double-walled).  There are some extra considerations for the two types of bulb.

Tungsten halogen

The use of unfiltered desktop lamps should be discouraged if they are used for more than 2 hours per day and are sited within 0.6 m or 2 feet of the user. If a lamp is fitted with a double-walled bulb, but the outer wall is broken, it should not be used.  A lot of smaller tungsten halogen bulbs have a filter incorporated.  Larger tube lamps, eg those used for uplighting and area illumination, may not have these fitted and should be checked.  Most commercially available tungsten halogen lamps are now supplied in sealed luminaires which contain a reflector and the necessary filtration to remove harmful UV radiation.

CFLs

In a limited number of circumstances UV exposure from CFLs can exceed guideline levels. CFLs should not be used in close proximity (distances of less than 30 cm or one foot) to people for longer than one hour.

The risks from CFLs can be reduced to a safe level by:

• moving the CFL away from people to a safe distance (>30 cm or 1 foot),
• shading the bulb either physically to direct the UV light away from the user or with a filter to stop UV emissions, or
• using a double-encapsulated bulb.

Action by visiting staff

Special visits on this subject are not required. Visiting staff who come across tungsten halogen lamps or CFLs being used in the workplace should take note of the conditions in which they are being used and, if appropriate, send a copy of the relevant appendix to the occupier or refer them to the document on HSE’s website.

Staff should check that the issue of workplace lighting has been risk assessed. HSE has published guidance to assist dutyholders as HSG 38 ‘Lighting at work’. In carrying out the risk assessment, dutyholders should consider duration of exposure and whether individuals have any relevant health concerns.

Staff may wish to note how such lamps are used when lit, fine-detail work is taking place, eg electronic component assembly, watch repair and jewellery making.

Cancellation of instructions

LAC 60/6 and OC 559/6 – cancel and destroy