Lasers, AOR, UV

Scope

This experimental work instruction applies to the use of lasers, artificial optical radiation (AOR), and UV Light.

 

Pre-visit

User Principal Investigator shall provide the following to the Diamond Local Contact at least eight weeks prior to the experiment at Diamond:

• Essential Information Requirements (see below) for User-provided equipment.

Assurances that User-provided equipment achieves the relevant:

• Essential Safety Requirements (see below).

Assurances that Users coming to Diamond achieve the relevant:

• Essential Competency Requirements (see below).

Assurance that the equipment is compliant with the safety requirements of the home institution.

Diamond Local Contact shall ensure compliance with the following for Diamond provided equipment:

• Essential Information Requirements (see below);
• Essential Safety Requirements (see below);
• Essential Competency Requirements (see below).

 

Pre-experiment

Diamond Local Contact shall ensure that the above pre-visit requirements for User provided equipment is reviewed by a laser competent person (e.g., a Laser Responsible Officer).  This shall include inspection of the equipment.

 

Experimental Setup

Diamond Local Contact & User Visit Principal Investigator shall collaborate to ensure adherence to:

• Essential Experimental Setup Checklist (see below).

 

Operation

Diamond Local Contact & User Visit Principal Investigator shall collaborate to ensure adherence to:

• Essential Operational Checklist (see below).

 

Essential Safety Requirements

Equipment shall be:

• Suitable for task, and the lowest hazard class and power output practicable;
• Safest feasible option for all activities, including operation, different modes, alignment, etc.;
• Rated and compatible with the intended experiment, laser, AOR or UV light, sample environment and set-up conditions at Diamond;
• Suitably tested by a competent person or body to ensure safe operation at Diamond.  Non-standard set-ups shall be commissioned and tested prior to coming to Diamond;
• Safely packaged & transported to Diamond to prevent damage that could affect safe operation;
• Suitably risk assessed, identifying failure modes, safety controls and emergency controls.(Ref Essential Hazard & Failure Mode Checklist and Checklist of Controls for Laser Systems by Classification) or Checklist of Controls for UV Systems by Risk Group, as applicable;
• Fitted with suitable safety devices (e.g., over-temperature cut-outs, enclosure interlocks);
• Labelling: Equipment CE / UKCA marked or has an appropriate declaration of conformity;
• Remote operation enabled as far as possible; and
• Diamond provided laser equipment shall be assessed and compliant with Laser Safety (HAS-PRC-0023

 

Essential Information Requirements

Information required:

• A full description of the proposed experimental setup & technical specifications.
• Artificial Optical Radiation (AOR) details including wavelength(s), type of source, power density, total power output(s), etc.
• Laser details including:
  • Type of laser
  • Laser class (1 – 4)
  • Wavelength (nm)
  • Mode (continuous wave or pulsed)
  • Power output (W)
  • Pulse energy (W)
  • Pulse duration (s)
  • Pulse rate (pulses / s)
• Sample environment details including power levels, sample temperatures, safe distances, etc.
• Safe operating procedure / instructions for any equipment not provided by Diamond.
• Unique Identification mark of any equipment not provided by Diamond, i.e., its serial number.  
• Manufacturing QA documents.
• Assurances and evidence that all equipment has full up-to-date test and calibration certificates (where applicable).
• Interlock details, if linking with the beamline hutch interlocks.

 

Essential Competency Requirements

Person setting up experimental equipment shall:

• Have sufficient experience of setup, test and operation of the equipment, gases, risks and required safety controls to ensure safe setup;
• Have sufficient skills and be practiced in safe setup and operation of the equipment, gases, risks and required safety controls used in the experiment; and
• Have sufficient knowledge of the essential safety requirements of the equipment to ensure safe setup.

Persons operating equipment shall:

• Have sufficient experience and be practiced in safe use of the specific equipment, substances and required safety controls to ensure safe operation;
• Have sufficient skills and be practiced in safe use of the specific equipment, substances and required safety controls used in the experiment;
• Have sufficient knowledge of the essential equipment safety requirements, substances, and safety controls to ensure safe operation. This includes knowing when to stop operations and what to do in the case of an emergency; and
• Be suitably supervised if they do not have sufficient skills, knowledge, and experience.

 

Essential Experimental Setup Checklist

• Persons setting up the equipment meet the Essential Competency Requirements.
• Interlocks: enclosures are suitably equipped with interlock systems.
• Appropriate warning signage is displayed both on the equipment and the outer hutch doors.
• Shielding is in place to enclose sources of AOR or UV light radiation.
• Electrical safety devices (e.g., emergency stops) are in place and confirmed functional.
• Power status: it is clear and unambiguous when the equipment is live or powered off.
• Energy setting of the equipment (voltage, current, power, etc.) has been set to the lowest level for the work.
• Electrical safety: equipment has been electrically checked by a competent person.
• Visual inspection of the setup.
• Manufacturer’s instructions (where applicable) have been followed during setting up.
• Remote shutdown is enabled for all experimental equipment. 
• Modifications from planned setup have been checked by a competent person.

 

Essential Operation Checklist

• Persons operating the equipment meet the Essential Competency Requirements.
• Visual check of the setup is carried out before every operation.
• Modifications to the planned setup are done by a competent person and checked against the Essential Experimental Setup Checklist.
• Safety controls stated in the User Experimental Risk Assessment (ERA) (or lab form) are applied, and the ERA has been graded and validated.
• Safety controls stated in both the beamline risk assessment and any Diamond equipment risk assessment are applied. 
• Lone-working prohibition is in place and understood by all persons supervising the experiment.
• Suitable manning to ensure a suitable level of manning on the beamline.
• Suitable supervision of the experiment is in place to ensure safety.
• Failure modes of the set-up are understood by all persons supervising the experiment.
• PPE identified on the risk assessment is provided, it fits, it is in good condition, and all operators are proficient in its correct usage.
• Emergency conditions and required action is understood by all persons supervising the experiment.
• Emergency action on uncontrolled AOR / UV light exposure is understood by all persons supervising the experiment.
• Emergency action on the fire alarm sounding is understood by all persons supervising the experiment.
• Emergency action on gas detection sounding is understood by all persons supervising the experiment.
• Emergency action on power outage is understood by all persons supervising the experiment.
• If safety issues are identified, the Principal Beamline Scientist (PBS) must be contacted, and the issues resolved before continuing with the experiment.

 

Essential Hazard & Failure Mode Checklist

The main hazards are:

• Light / laser exposure damage to eyes (Arc eye, blindness, permanent damage);
• Light exposure damage to skin (burns, increased risk of cancer);
• Hot surface contact;
• Fire resulting from failure of components (e.g., heating element, supply leads, power leads, power supply or other component);
• Fire resulting from ignition of flammable / combustible material from laser / AOR exposure;
• Electrocution resulting from contact with energized circuit (high voltage / current);
• High voltage current burns resulting from contact with energized circuit;
• Hazardous gases;
• High voltage current burns; and
• Skin exposure to UV causing injury to skin (erythema) or eye damage (cornea, lens, or retina).

Principal failure modes are:

• Poor equipment and / or system design;
• Poor installation / setup;
• Misaligned optics and upwardly directed beams (reflections from windows and beam splinters);
• Poor maintenance of equipment;
• Inadequate repairs or modifications;
• An unsafe system of work;
• Operator error, poor training / supervision;
• Poor installation / setup;
• Incorrectly specified, selected, availability, or wearing of eye protection;
• By-passing of interlocks;
• Addition of reflective materials into the beam paths;
• Lack of protection from non-beam hazards;
• Improper methods of handling high voltage;
• Operating unfamiliar equipment or working outside of competence limits;
• Loose optical components on an optical table; and
• Overconfidence leading to complacency in safety requirements.

 

Checklist of Controls for Laser Systems by Classification

 

Class	1 / 1M	2	2M	3R	3B	4
Engineered Controls
Protective enclosures					X	X
Beam paths enclosed as far as reasonable			X	X	X	X
Beam paths directed away from doors and windows			X	X	X	X
Interlocks on removable housings					X	X
Service access panels only removable by tooling					X	X
Beam stop or beam attenuator					X	X
Emergency stop button			X	X	X	X
Activation warning system					X	X
Key control					X	X
Remote interlock connector					X	X
Mat black surfaces and tooling					X	X
Viewing portals, display screens, and collecting optics					X	X
Remote laser firing and monitoring					X	X
Admin Controls
Risk Assessment	X	X	X	X	X	X
Local Rules	X	X	X	X	X	X
Laser controlled area					X	X
Equipment labels	X	X	X	X	X	X
Laser area warning signs			X	X	X	X
NOHD determined and marked					X	X
Training for people at risk			X	X	X	X
Competence assessment of operators	X	X	X	X	X	X
PPE
Eye protection				X	X	X
Skin protection					X	X

 

 

Checklist of Controls for UV Systems by Risk Group

 

Risk Group	RG0	RG1	RG2	RG3
Controls
Read the manufacturer's instructions.	X	X	X	X
Follow the control in the procedure.	X	X	X	X
Avoid unnecessary exposure to eyes or skin	X	X	X	X
Do not expose others or modify the experimental setup agreed with the local contact.	X	X	X	X
Connect the UV power supply to the hutch interlock where possible. Don't defeat interlock.			X	X
Don't remove the covers.	X	X	X	X
PPE
Wear standard laboratory clothing, including a fully buttoned lab coat, long trousers, and closed-toe shoes, while paying attention to the gaps around the neck and wrist areas.		X	X	X
Face / Eye protection – EN 166 - EN 170 certified face shield must be worn to protect the face and eye.  In addition, if the spectrum extends over 400 nm, protective eyewear must be worn with the face visor to prevent blue light hazards.		X	X	X
Gloves – wear gloves, ensuring the gaps are covered between the tops of the gloves and the bottom of the lab coat sleeves.		X	X	X

 

IEC 62471 describes the degree of risk from potential optical radiation hazards to minimise the need for further control measures for risk management.  The defined risk groups are Exempt Group (RG0) for no risk, Risk Group 1 (RG1) for low, Risk Group 2 (RG2) for medium and Risk Group 3 (RG3) for high risk.  For more information, read the UV radiation safety guide (CEO-HP-PRC-0022).