Laser Classification & Risk Identification: LSO Briefing

Purpose:

The Topic Briefing Sheet provides learners with concise, assessor-prepared notes summarizing the theory, definitions, and core principles of laser classifications, associated hazards, and risk identification. It forms the foundation for safe laser operations in compliance with UK legislation and standards.

Laser Classification Overview

Definition:

Laser classification categorizes lasers according to their hazard potential to eyes and skin, based on power output, wavelength, and exposure time.

International & UK Standard:

• BS EN 60825-1:2014 – Safety of laser products
• UK Control of Artificial Optical Radiation at Work Regulations (AOR) 2010

Laser Classes:

Class	Description	Typical Hazard	Workplace Example
Class 1	Safe under normal use	No eye or skin hazard	Laser printers, CD/DVD players
Class 1M	Safe unless used with optical instruments	Hazard if viewed through telescopes or microscopes	Laser measuring devices
Class 2	Low-power visible lasers (≤1 mW)	Eye hazard from direct viewing; blink reflex provides protection	Laser pointers
Class 2M	Same as Class 2 but hazardous when viewed with optical instruments	Eye hazard via magnification	Alignment tools using lasers
Class 3R	Medium power (≤5 mW)	Eye hazard if directly viewed	Medical diagnostic devices
Class 3B	Medium-high power	Eye and minimal skin hazard from direct beam	Nd:YAG lasers for hair removal
Class 4	High power	Eye and skin hazard; fire risk; hazardous reflections	CO₂ surgical lasers, industrial cutting lasers

Laser Hazards

Types of Hazards:

1.Photochemical Risks

• Caused by ultraviolet (UV) and some visible lasers
• Can lead to retinal or skin damage over time
• Example: UV lasers in research labs

2.Thermal Risks

• Heat generated by laser absorption in tissue or materials
• Can burn skin or eyes instantly
• Example: CO₂ laser skin resurfacing

3.Mechanical Risks

• Rapid expansion or shock from pulsed lasers
• Can cause tissue disruption or eye injury
• Example: Q-switched lasers in tattoo removal

Types of Beam Hazards

Beam Type	Definition	Workplace Example
Direct Beam	Laser light directly entering the eye or hitting skin	Operator error during Nd:YAG hair removal
Reflected Beam	Laser light bouncing off shiny surfaces	Metal reflection during industrial laser cutting
Scattered Beam	Light scattering from surfaces or aerosols	Laser procedure near reflective tiles or surgical instruments

Biological Impacts

Eyes:

• Retinal burns from visible or near-infrared lasers (400–1400 nm)
• Corneal or lens damage from UV or far-infrared lasers
• Safety: Use laser safety goggles with correct optical density (OD)

Skin:

• Thermal burns
• Photosensitivity reactions from photochemical exposure
• Safety: Protective clothing and controlled access zones

Risk Identification and Assessment

Core Principles:

1. Workplace Survey: Identify laser locations, reflective surfaces, ventilation, and proximity to personnel.
2. Hazard Analysis: Identify laser class, beam type, and exposure duration.
3. Control Measures:
   o Controlled areas
   o Interlocks and warning lights
   o PPE (goggles, gloves)
   o Engineering controls (beam stops, screens, LEV)
4. Documentation:
   o Laser Risk Assessment (LRA) forms per UK AOR 2010 and BS EN 60825-1
   o Recording hazards, controls, and responsibilities

Key UK Legislation / Standards:

• HSWA 1974 – Health and Safety at Work Act
• AOR 2010 – Control of Artificial Optical Radiation at Work Regulations
• BS EN 60825-1:2014 – Safety of Laser Products
• PUWER 1998 – Provision and Use of Work Equipment Regulations
• COSHH 2002 – Control of Substances Hazardous to Health (for laser plume exposure)

Learner Task

Instructions:

1. Create a summary table of all laser classes (1–4) including:
   • Hazard type
   • Workplace example
   • Recommended control measures
2. Identify three potential hazards in your workplace or training environment:
   • Class of laser involved
   • Beam type (direct, reflected, scattered)
   • Possible biological impact (eye/skin)
3. Complete a mock risk assessment for one laser activity, documenting:
   • Laser type and class
   • o Identified hazards
   • o Proposed control measures
   • o Reference relevant UK legislation