Laser risk assessments and control measures
Guidance on completing risk assessments for lasers and the control measures to put in place
In line with the Management of Health & Safety at Work regulations, the risks associated with laser systems must be suitably and sufficiently assessed. The purpose of the assessment is to systematically identify all hazards associated with the laser system and assess the risk arising from both normal and/or non-routine use.
The British Standard of control for the normal operation of lasers is given in LS-9 Laser User Precautions
These minimum requirements must be met
Where an assessment identifies a specific risk with the laser system, then a hierarchy of control must be followed. For non-beam hazards these are outlined within individual University Policy Statements. For beam hazards, the preferred starting point for all lasers is fully enclosed with fixed guarding.
If a risk assessment identifies that it is not practical to fully enclose the laser at all times, then it must be justified within the assessment and a suitable combination of engineering, administrative and personal protective controls identified. In any event, the use of personal protective equipment must always be the last option and if it is necessary, there must be clear administrative controls to ensure it is correctly applied.
It is important to identify controls that are not overly complicated. A balance needs to be met between ensuring the safety of individuals and avoiding making procedures so complicated that they are difficult to apply. Equally, it is important to avoid introducing confusing arrangements, such as the use of personal protective equipment where the risk from a beam is either unlikely or of inadequate power (e.g. use of Class 1 or 2 lasers).
Personal Protective Equipment (PPE)
Personal protective equipment in the context of laser safety normally implies the use of laser protective eyewear. As with any PPE though, there are serious limitations when relying on laser protective eyewear alone. Notably, it requires careful selection against all possible wavelengths and as such, this could result in the need for more than one type of protective eyewear to cover all potential operating conditions. It also requires very careful training and supervision to ensure the eyewear is actually worn, particularly as laser eyewear, by its nature, will reduce normal viewing as well. In some cases, this will actually increase the risk, as people might be unable to see the beam or indeed any other non-beam hazard. Most importantly, when laser eye protection is required, it generally implies there is both an eye and a skin hazard. The risk to the skin must not be discounted, although the options for protection are significantly less.
If we assume that more than one person at any one time is likely to require suitable eye protection, the actual cost of implementing personal eye protection may be greater than the cost of implementing appropriate guarding and administrative controls, albeit with a lower level of confidence in its control.
Personal Protective Eyewear must only be used where engineering and administrative controls cannot adequately control the risk
Your supervisor must determine the need for personal protective equipment as part of the risk assessment process. Laser eye protection should only be used if all other types of controls have first been considered and where a risk of exposure to a laser above the Maximum Permissible Exposure limit still remains.
Where laser eye protection is deemed necessary, then the following must be applied:
- There must be a documented in-house assessment of the required specification of eyewear for each type of laser, taking into account the varying wavelengths used and the degree of optical clarity required. The assessment must state both the optical density and ‘scale factor’ attenuation for all relevant wavelengths. It is not appropriate to rely on laser equipment suppliers to undertake this assessment or specify eyewear. Eyewear must be selected against the relevant standard, BS EN 207 for general use and BS EN 208 for alignment procedures.
- There must be evidence, either on the frames or in accompanying documents, that the eyewear used is CE marked and conforms to the required standard. Eyewear that does not meet these requirements must be replaced.
- The protective eyewear should be labelled indicating which laser(s) and wavelengths they are suitable for.
- Where multiple lasers are used in a single area, then each set of protective eyewear must be unambiguously marked to ensure correct selection for the relevant laser.
- When not in use, protective eyewear must be stored correctly to prevent damage. It must not be left on benches but stored in protective cases or suitable racking.
- Individuals must be trained in the selection, fitting, storage, and inspection of protective eyewear.
Laser Bee Software
The University holds a site license for the use of the Laser Bee software. Laser Bee can be used to calculate Maximum Permissible Exposure (MPE) limits for specific lasers, as well as the Nominal Ocular Hazard Distance (NOHD) and eyewear protection values, both in terms of normal use and alignment (visible lasers only).
By downloading the software you are agreeing to comply with the University’s software license agreement.
In particularly, the software must only be used by University of Oxford personnel and for University of Oxford related work. If and when you leave the University of Oxford, you must delete the software from all relevant devices.
In order to calculate MPE, NOHD and eyewear protection values, you will need a certain amount of laser safety knowledge to ensure you select and use the correct laser specifications. Individuals involved in these types of calculations are advised to attend the Laser Safety for Research Supervisors training.
- LS-2 Laser risk assessment proforma (Word)
- LS-6 Laser risk assessment guidance (PDF)
- Example of completed LS-2 form (PDF)
- LS-7 Laser beam hazards (PDF)
- LS-8 Laser classification (PDF)
- LS-9 Laser user precautions (PDF)
- LS-3 Laser local rules (Word)
- LS-10 Laser local rules guidance (PDF)
- Example of completed LS-3 Form (PDF)