What do barcode scanners, eye surgery, and high-speed internet have in common? The answer is ‘the laser’ – a remarkable invention that channels light into one of the most versatile tools of the modern age. Theodore H. Maiman succeeded in operating the first functional laser in 1960; since then, lasers have undergone constant improvement to become the incredibly precise instruments we use today.
Today, lasers play a pivotal role in our everyday lives. They are found in countless technologies, from metal cutting machines and dental drills to measurement systems and CD players. They also play a key role in eye surgery, tattoo removal, hair restoration and many other treatments.
But what actually are lasers?
A laser is a device that produces a very narrow beam of light. Light is released following a process of optical amplification based on the stimulated emission of radiation. The word ‘laser’ is actually an acronym for Light Amplification by Stimulated Emission of Radiation.
Laser light has specific properties, it is:
• Monochromatic: it contains one specific wavelength of light (one colour). Other sources of light have a range of wavelengths.
• Coherent: it is ‘organised’ – all the light waves are in a phase with their peaks and troughs being at the same point. This is a unique property of lasers and one of the reasons why the beams are so intense.
• Directional: laser light has a very tight beam; it is strong and concentrated. Whereas a flashlight for example, releases light in many directions, the light is weak and diffuse.
Lasers produce highly coherent, directional beams of monochromatic light. Therefore, laser beams tend to have a high intensity and a very high ‘brightness’ – in fact surgical lasers can be up to 100 times brighter than the sun.
How do they work?
Any object that emits light does so through the action of electrons shifting their orbits and releasing photons (light particles). A laser is a device that controls the way that the energised atoms release photons.
A laser contains a lasing medium, such as glass, crystal or gas, that is sandwiched between two mirrors in an optical cavity.
The lasing material is ‘pumped’ using an electrical current or a source of light which ‘excites’ the electrons to move into a higher-energy orbit around the atom. When the electrons return to their normal orbit, they emit photons (light) that bounce back and forth between the mirrors and through the lasing medium stimulating almost an exact clone of themselves. The cloning process repeats and repeats until the photons are amplified enough for them to move past the mirrors in perfect unison – resulting in laser output.
Laser Classification
In the UK, lasers are classified according to the British Standard BS EN 60825-1. The classification system divides lasers into classes based on their potential to cause harm.
Class 1: Safe during normal operation; often found in CD/DVD players and barcode scanners.
Class 1M: Safe unless viewed with optical aids like binoculars.
Class 2: Low-power visible lasers; safe for accidental short exposure (e.g., laser pointers under 1 mW).
Class 2M: Similar to Class 2 but hazardous when viewed with optical aids.
Class 3R: Low risk but potentially hazardous if viewed directly for extended periods.
Class 3B: Direct exposure to the beam is dangerous to eyes and potentially skin.
Class 4: High-power lasers that can cause severe eye and skin injuries and may present fire hazards.
Hazards of Laser Use
The primary risks from lasers are eye injuries and skin burns. The eye is particularly vulnerable because the lens can focus laser light onto the retina, causing permanent damage. Even brief exposure to high-powered beams could result in blindness. Skin exposure to high-intensity lasers can cause burns, and Class 4 lasers may ignite flammable materials.
Non-beam hazards also exist, such as electrical risks from laser power supplies, chemical hazards from laser dyes, and fume inhalation from materials vaporised by the beam.
Regulations and Guidance
In the UK, laser safety is overseen by the Health and Safety Executive (HSE) and guided by the Control of Artificial Optical Radiation at Work Regulations 2010. Employers must assess risks, implement control measures, and provide training to anyone working with or near lasers. Key recommendations include:
Risk Assessment – Identify hazards, assess exposure levels, and determine necessary control measures.
Engineering Controls – Use beam enclosures, interlocks, and key switches to prevent accidental exposure.
Administrative Controls – Implement safe operating procedures, restrict access to authorised personnel, and provide training.
Personal Protective Equipment (PPE) – Use of suitable laser safety eyewear where engineering and administrative controls cannot fully eliminate risk.
Signage and Labelling – Display warning signs in areas where hazardous lasers are in use.
Regulatory bodies strongly recommend the appointment of a Laser Protection Adviser to ensure safe working practices and to provide specialist expertise in laser safety. SGA can act in this capacity for you, see our Website for further details.
A further essential appointment is that of the Laser Protection Supervisor (LPS). The LPS is an appointed person(s) within the workplace who oversees day-to-day safe use of the lasers.
SGA can also provide essential training for Laser Protection Supervisors (LPS) and authorised laser operators via our online Laser Safety Core of Knowledge course. Our course is suitable for operators of Class 3B or 4 lasers and/or non-laser (IPL) light sources and enables the delegate to be appointed as an LPS.
Conclusion
Laser safety in the UK is built on a framework of classification, regulation, and best practice. By understanding the risks and following established safety measures, industries and individuals can harness the benefits of laser technology without compromising health and safety. Whether in a hospital operating theatre, a manufacturing plant, or a light show, the principle remains the same: control the beam, protect the people.
