Laser welders – safety requirements and purchase guidance

10 June 2026

Laser welders use powerful beams to join materials – but come with serious risks. Class 4 systems require strict safety controls and specialist setups.

People working at a shared desk in a bright lab space. One person is using a laptop displaying a webpage, while another is focused on a tablet with a keyboard. There are printed materials and devices are spread across the table.

Laser welders are used to join metals and thermoplastics using extremely powerful laser beams. These beams can cause instantaneous and permanent eye damage if not properly controlled.

Most laser welders are classified as Class 4 laser products, the highest risk category.

Safety requirements for Class 4 laser welders

Class 4 laser systems must meet the requirements of the UCL Artificial Optical Radiation Safety Standard and typically require:

Appointment of a Laser Safety Officer.
Dedicated room or purchase of specialised laser safety enclosures or curtains.
Adequate ventilation to manage welding fumes.
Specialist training for all users.
Use of specialist Personal Protective Equipment (PPE).

Common procurement issues

There have been cases where:

Companies incorrectly describe equipment as Class 1 when it is actually Class 4.
Purchases are made without confirming suitable installation space or controls.

This can result in costly modifications, delays and restrictions on how the equipment can be used.

Action to take

Before purchasing any Class 4 lasers, departments must consult the Radiation Protection Team to ensure the safety requirements for use of the equipment have been considered and are in place.

Further information

Laser safety site (UCL login required) – our 10-step guide to safe laser use
Optical radiation (including lasers) – legal requirements, risks, and control measures for laser use in the workplace | HSE

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