Laser Safety Code of Practice

University of Brighton

1.Introduction

This Code of Practice is approved by the University’s RadiationProtection Sub-Committee. It supports the University Laser Safety Policy (included in Section 3 of this document) by providing more detailed guidance to all staff and students who use lasers in their work.

Responsibility for complying with the Laser Safety Code of Practice rests initially with the Academic Supervisor and ultimately with the Head of School.

2.Laser classifications

2.1.Definitions

Laser system

A Laser system is a system containing one or more lasers associated with a single application or process and under the control of a single operator, i.e. lasers that are exchanged on the same system or are running simultaneously on the same experiment (e.g. pump laser and main laser). There is more than one laser system if the lasers are not operating together or are used by different operators although mounted in the same area.

Laser product

A laser product is a piece of equipment containing a laser system. The product may be given a low classification even though it contains a higher classification laser system, provided that there are engineering controls to prevent access to the totally enclosed embedded system.

Designated Laser Area

A Designated Laser Area (DLA) is an area or room where one or more Class 3B and/or Class 4 lasers are in use. Signage is mandatory at the entrance to the area/room.

Maximum Permissible Exposure Levels (MPE)

Maximum Permissible Exposure limits are those levels of laser radiation to which, in normal circumstances, persons may be exposed without suffering adverse effects. A guide to MPE levels is given in BS EN 60825-1. They are based upon biological data collected to date.

Accessible Emission Limit (AEL)

The Accessible Emission Limit is the maximum level of laser radiation which the laser can emit (and be accessible) over its full range capability during operation at any time after its manufacture. The AEL takes into account the laser wavelength, exposure duration (for Continuous Wave and pulsed lasers) and viewing conditions of the laser radiation. BS EN 60825-1 provides tables of AEL values for each class of laser. These specify the maximum output for a given wavelength and emission duration within each Laser Class.

2.2.Laser hazard classification

Because of the wide ranges possible for the wavelength, energy content and pulse characteristics of laser beams, the hazards arising from their use vary widely. A system of laser classification is used to indicate the level of laser beam hazard shown below, with higher numbers indicating greater hazard.

It is normally the responsibility of the laser manufacturer to provide the correct classification of a laser product; however any person who modifies substantially the laser product must re-classify (e.g. downgrade a Class 4 product into Class 1 by totally enclosing it in an interlocked box). This classification is made on the basis of a combination of output power(s) and wavelength(s) of the accessible laser radiation over the full range of capability during operation at any time after manufacture which results in its allocation to the highest appropriate class.

Class 1, 1M

Class 1lasers are safe under reasonably foreseeable conditions of operation. The most limiting MPE values cannot be exceeded and no specific safety controls are required.
For CW (Continuous Wave) visible lasers, the Accessible Emission Limit is 70 microwatts.
Class 1 operation cannot be claimed for a laser product containing an embedded laser of a higher class unless full-interlocked high-integrity enclosures using fail-safe interlocks or other suitable engineering control measures are incorporated.

Class 1M emit a large diameter or widely divergent beam (wavelength range 302.5 – 4000 nm) of safe power density as Class1 but which may be hazardous to the eyes under certain conditions if gathering optics are used.

Class 2, 2M

Visible lasers only, for which the MPE cannot be exceeded in less than 0.25 seconds.
For CW (Continuous Wave) the AEL is 1 mW.

Class 2M emit a large diameter or widely divergent beam. As Class 2, but not safe when viewed with gathering optics.

Class 3R

Lasers that emit in the wavelength range 302.5 nm to 1 mm where direct intra-beam viewing is potentially hazardous but the risk is lower than for class 3B. The AEL is within five times the AEL of Class 2in the wavelength range 400 to 700 nm and within five times the AEL of Class 1 at other wavelengths.

Class 3B

Applies to visible and/or invisible laser radiation not exceeding specified AEL, which are for indication 0.5 W for Continuous Wave lasers and 105 Jm-2 for pulsed lasers (less for ultraviolet wavelengths).
Direct intra beam viewing or specular reflection is hazardous. Viewing diffuse reflections is normally safe provided the eye is no closer than 13 cm from the diffusing surface and the exposure duration is less than 10 seconds.

Class 4

Class 4 lasers are hazardous. Direct beam or reflected beam exposure is always hazardous and is likely to result in injury. They are capable of producing hazardous diffuse reflections to the eye and skin and could also constitute a fire hazard.

3.Universitylaser safety policy statement

In application of the Health and Safety at Work etc Act 1974, the Management of Health and Safety at Work Regulations 1999, and the Provision and Use of Work Equipment Regulation 1998, it is the policy of the University that all work involving lasers is carried out in such a way as to prevent undue risk either to those carrying out the work or to those who may otherwise be affected by the work. In particular, work with lasers will only be carried out after assessment of the hazards associated with it and providing that suitable facilities, local procedures and organisational arrangements are in place prior to first use. Work may only be carried out by trained competent workers and will be adequately supervised.

The University will seek to ensure that all relevant statutory requirements are complied with by appointing competent School Laser Safety Officers (SLSO)reporting to Heads of School and a University Laser Safety Adviser (LSA) reporting to the Deputy Director of Health and Safety.
They willcoordinate, oversee and advise on the safe usage of laser products according to thecurrent University Code of Practice, guidelines from the Association of University Radiation Protection Officers (AURPO 2007) and British Standard BS EN 60825.

The University Laser Safety Policy applies when Laser safety products of class 1M, 2M, 3R and above are present and in use within the school. This generally excludes office equipment such as laser printers, CD drives and most laser pointers.

4.Organisation of roles and responsibilities

Below is a description of the organisational arrangements related to laser safety at the university. The current list of the key responsible persons and their contact details can be found in section7.

4.1.Heads of School

Implementation of the University Laser Safety Code of Practice within a particular School lies with the Head of School. The Head of School should be satisfied that all relevant staff within their area of responsibility are aware of this policy.
To facilitate the implementation and monitoring of this policy, the Head of School should appoint a competent School Laser Safety Officer when lasers of class 1M, 2M, 3R and above are used in the School. The role of a School Laser Safety Officer is described below.
When appointing persons as School Laser Safety Officers, serious consideration should be given to the amount of time necessary to adequately carry out the associated duties and the person’s existing duties.Where necessary, some of the person’s existing duties may need to be transferred to another person/post.
It is recommended that the School Safety Officer should be consulted on this appointment, with advice from the Deputy Director of Health and Safety and Laser Safety Advisor sought as necessary.
Heads of School shall ensure that the Deputy Director of Health and Safety and Laser Safety Adviser are kept informed of their current nominated School Laser Safety Officer.

4.2.Laser Safety Adviser (LSA)

The Laser Safety Adviser (LSA) is appointed by the University Health and Safety Departmenton behalf of the Deputy Director of Health and Safetyin order to provide impartial professional advice and guidance on laser safety.
The LSA will:

Ensure that the University and Schools meet the safety requirements for the use of lasers and implements the requirements of BS EN 60825 and guidance from AURPO when lasers of Class 1M, 2M, 3Rand above are being used.
Provide laser safety advice and guidance to the Senior Management Team, Deans, Heads of School, School Laser Safety Officers, Academic Supervisors and Laser Users on request.
Write and keep under review the University Laser Safety Code of Practice.
Monitor forthcoming legislation, standards and good practice.
Ensure that safe operating procedures and systems of work are in place by the relevant Schools and coordinated by a School Laser Safety Officer
Ensure that all laser systems and users of class 3R and above are identified and registered with the Health and Safety Department.
Undertake annual inspections of laser systems of Class 1M, 2M, 3R and above to ensure compliance with the University Laser Safety Code of Practice and AURPO guidance; and make recommendations to the Head of School and Deputy Director of Health and Safety.
Report on laser safety to the University Radiation Sub-Committee.

The LSA has authority to prohibit the use of any laser installation or equipment if identified to give rise to a significant risk or harm to persons or if in breach of statutory regulations.

The LSA shall be qualified in laser safety management to the minimum level of qualification of Health Protection Agency Laser Safety Management Certificate and possess an adequate experience of using and supervising all classification of lasers within a wide range of organisations.

4.3.School Laser Safety Officers (SLSO)

The School Laser Safety Officer is appointed by the relevant Head of School where lasers of Class 1M, 2M, 3R and above are in use.
The SLSO is acting in a coordinating, advisory and monitoring role on matters relating to laser safety. The responsibility for ensuring that information provided is incorporated into risk assessment, that risk assessments are carried out and complied with rests with the Academic Supervisor (see section 3.4).
The SLSO will:

Be fully familiar with the University Laser Safety Code of Practice and assist the Head of School by developing, implementing and periodically reviewing the local rules, procedures and policy.
Advise the Head of School, Academic Supervisors, Laser Users and any other laser area personnel on laser safety risk assessment, engineering or administrative hazard controls and safety information and instructions.
Ensure that the Schools have undertaken suitable and sufficient risk assessments for all laser systems of class 1M, 2M, 3R and above and relevant Designated Laser Areas and correct labelling applied.
Monitor that safe working practices based on risk assessment are adopted locally.
Coordinate or provide (as necessary) the laser safety training required by the Laser Users, Academic Supervisors and any other laser area personnel.
Ensure that all personnel intending to work with Class 1M, 2M, 3R and above laser products have been identified and that training has been provided.
Keep an inventory of all laser systems and products of Class 1M, 2M, 3R and above used in the School and update the LSA whenever new lasers are purchased/de-commissioned or where there are changes in locations or changes in existing arrangements which are liable to affect the risk in the use of a laser system. This also extends to laser equipment on lease.
Monitor that all laser equipment and processes within the School are maintained in a safe condition and in compliance with appropriate statutory requirements.
Ensure that Personal Protection Equipment (PPE) is provided to, used and properly maintained by the Laser Users using laser systems requiring PPE (identified by risk assessment).
Liaise with the Laser Safety Adviser or the Health and Safety Departmentas appropriate for guidance on laser safety matters.
Participate in audits carried out by the Health and Safety Departmentas necessary.
Refer promptly to the Head of School or University Health and Safety Departmentany health and safety problem which cannot be resolved in a timescale appropriate to the risk.
Act with the delegated authority of the Head of School in matters of urgency relating to laser safety.

The SLSO shall be sufficiently competent through experience and/or qualification to carry out the role. They should also be of sufficient seniority and experience to be able to carry out their duties in relation to laser safety with the recognised authority of the Head of School.

4.4.Academic Supervisors

Academic Supervisors carry personal responsibility for carrying out risk assessments and developing safe working practices whenever using lasers as part of their teaching or research duties.

It is the responsibility of individual Academic Supervisors to provide adequate supervision and monitor/provide the training of the Laser Users under their supervision to ensure they are working in a manner which is compliant with the risk assessment, safe working practices and local safety rules.

Academic Supervisors are responsible for the day-to-day health and safety management of the research project, equipment and User under their supervision (including themselves if also User). This includes producing risk assessments and written schemes of work / Safe Operating Procedures (SOP), with advice from the SLSO as appropriate.

4.5.Laser Users

Laser Users are any end user of a laser system. The role of laser User is cumulative to any other role a person may have (e.g. a practising Academic Supervisor may also be a laser User too when carrying out experiments).

Laser Users are responsible for observing the local rules and schemes of work applicable to the lasers that will be used and to follow the guidance of their Academic Supervisor and School Laser Safety Officer.

Laser Users must attend training identified as necessary by either the LSA or SLSO.

Laser Users carry responsibility for their own safety and that of others that may be affected by their acts or omissions.

Laser Users must use and provide due care to the Personal Protective Equipment (PPE) provided.

Laser users shall not leave a laser experiment running unattended unless a risk assessment has established that it is safe to do so.

4.6.Occupational Safety and Health Services

Occupational Safety and Health Serviceswill:

Maintain a register of all University laser systems of class 1M, 2M, 3R and above.
Maintain a register of all University users of laser products of Class 1M, 2M, 3R and above.
Undertake yearly inspections of Laser equipment and facilities of class 1M, 2M, 3R and above with the Laser Safety Adviser.
Facilitate access to the Laser Safety Code of Practice and relevant forms, training material, guidance notes and standards.
Organise university laser safety training/good practice workshops when appropriate.

5.General safety procedures

5.1.Administrative arrangements

No work with the more hazardous classes of laser (Class 3R, 3B and 4) may be carried out unless those laser systems and the users of them are risk assessed and registered within the School where they are based. Details of user and laser system registering procedures are provided in sections 5.9 and 5.8 respectively. Guidelines on laser specific risk assessments are given in section 5.2.

When identified as required from a risk assessment, adequate PPE should be used and correctly maintained. More information is given in sections 5.3 and 5.4.

Training of laser Users is required prior to work commencing. Details of training requirements are given in section 5.5.

The School Laser Safety Officer should maintain the records for the relevant School.
Occupational Safety and Health Services, via the LSA,will maintain the records of laser systems and users for the University as a whole and will request, at a minimum, an annual update from each SLSO.

School level local rules on laser safety should be implemented by the Head of School and SLSO to help safe working practice and compliance to current regulations. Guidance is provided in section 5.6. Regular School audits should be performed by the SLSO to ensure the compliance to regulations, local rules and university code of practice. Outcomes of the audits should be communicated to the Head of School and LSA. Further details on audits can be found in sections 5.10 and 5.11.

Procedures in case of an accident should be put in place for each laser system / experiment and written emergency instructions should be provided as part of the scheme of work/SOP documents by the equipment. Further details can be found in section 5.12.

5.2.Risk assessments and specific hazards associated with laser equipment

In accordance to Health and Safety at Work Regulations, risk assessments must be carried out where use of work equipment involves possible exposure to significant hazards.