Laser Safety Glossary: Key Terms Every LSO Must Know
Laser Classification, Hazards, and Risk Identification
Purpose:
The Glossary-Building Activity enables learners to compile, understand, and apply key terminology associated with laser safety. This enhances comprehension of laser hazards, risk control, and safe operation in line with UK legislation and standards.
Instructions for Learners:
- Complete the glossary table by filling in:
- Term
- Definition
- Workplace example
- Relevant UK legislation or standard
- Use this glossary as a reference for risk assessments, SOPs, and laser safety procedures.
- Include visual aids or diagrams where necessary to illustrate concepts.
Key Terms and Examples
| Term | Definition | Workplace Example | UK Legislation/Standard |
| Laser | Device producing a coherent, monochromatic, and collimated light beam | CO₂ laser used in surgical cutting | HSWA 1974, BS EN 60825-1 |
| Laser Classification | System categorizing lasers by hazard level (Class 1–4) | Class 4 fiber laser cutting metal | BS EN 60825-1, AOR 2010 |
| Direct Beam | Laser light striking eyes or skin directly | Nd:YAG laser for tattoo removal | HSWA 1974, BS EN 60825-1 |
| Reflected Beam | Laser light bouncing off a reflective surface | Metal tray reflecting a Class 4 laser in a clinic | BS EN 60825-1, AOR 2010 |
| Scattered Beam | Diffuse reflection of laser light from tissue or materials | Laser tattoo removal generating scattered light | AOR 2010, COSHH 2002 |
| Photochemical Risk | Tissue damage from chemical reactions induced by UV or blue light | UV laser in research lab causing skin erythema | AOR 2010, HSWA 1974 |
| Thermal Risk | Tissue heating caused by absorption of laser energy | CO₂ surgical laser causing burns | BS EN 60825-1, PUWER 1998 |
| Mechanical Risk | Physical disruption of tissue from highintensity pulses | Q-switched laser for tattoo removal | BS EN 60825-14 |
| Maximum Permissible Exposure (MPE) | Threshold level of laser radiation exposure deemed safe | Operator eye exposure during Nd:YAG laser session | AOR 2010 |
| Beam Divergence | Measure of beam spread over distance | Laser alignment tools in lab | BS EN 60825-1 |
| Coherence | Phase relationship of light waves enabling focused energy delivery | Phase relationship of light waves enabling focused energy delivery | BS EN 60825-1 |
| Controlled Area | Restricted space where hazardous lasers operate | Class 4 laser cutting room | HSWA 1974, BS EN 60825-1 |
| Interlock | Safety device preventing laser operation when access is unsafe | Door interlock on laser treatment room | PUWER 1998, BS EN 60825-1 |
| Laser Plume | Smoke or aerosol generated by lasertissue interaction | Surgical laser plume during dermatology procedures | COSHH 2002 |
| Optical Density (OD) | Measure of protection level of laser goggles | OD 5+ goggles for Nd:YAG laser | PPE Regulations 1992, BS EN 60825-1 |
| Engineering Controls | Physical measures to reduce laser exposure risk | Beam stops, enclosures,ventilation | HSWA 1974, PUWER 1998 |
| Administrative Controls | Policies and procedures to minimize exposure | SOPs, training, access restrictions | HSWA 1974, AOR 2010 |
| PPE | Personal protective equipment for eye, skin, or respiratory protection | Laser-rated goggles, gloves, lab coats | PPE Regulations 1992, COSHH 2002 |
| Risk Assessment | Process of identifying hazards and implementing controls | Laser risk assessment for industrial laser cutting | Management of Health and Safety at Work Regulations 1999 |
| Continuous Wave Laser | Laser emitting a constant beam | CO₂ cutting laser | BS EN 60825-1 |
| Pulsed Laser | Laser emitting short high-energy pulses | Q-switched Nd:YAG tattoo removal | BS EN 60825-14 |
Visual Examples to Include:
- Laser Hazard Diagram:
- Illustrates direct, reflected, and scattered beams in a controlled room.
- Beam Divergence Example:
- Shows how a beam spreads over distance and affects exposure risk.
- Laser Risk Flowchart:
- Laser → Hazard → Risk → Control Measure → Residual Risk
Learner Task
Instructions:
- Complete a full glossary:
- Add 5 additional laser-related terms not included in the table
- Provide definitions, workplace examples, and UK legislation references
- Create a visual diagram linking 10 glossary terms:
o Show how they interact in a real workplace scenario - Mini Reflection:
- Write 250–300 words on how understanding this terminology helps improve laser safety practices in the workplace
- Optional Exercise:
- Develop a poster or flashcards with glossary terms and visuals for staff induction or training purposes