UV Risk Assessment: A Complete Guide for UK Workplaces

If your organisation uses artificial UV light sources, conducting a thorough UV risk assessment is a legal requirement. The Control of Artificial Optical Radiation at Work Regulations 2010 (CAOR 2010) and the underpinning EU Directive 2006/25/EC place clear obligations on employers to identify, assess and control the risks from UV radiation in the workplace. For health and safety professionals, understanding what a compliant assessment actually involves – and where specialist expertise is essential, is critical to getting this right.

This guide explains the legal framework, the exposure limits that apply, the steps involved in a compliant UV risk assessment, and the areas where attempting to work in-house without specialist support can leave your organisation dangerously exposed.

Why UV Risk Assessment Matters in the Workplace

Ultraviolet radiation is invisible, painless in the short term, and widely underestimated as a workplace hazard. Yet repeated or excessive exposure to UV radiation (180 to 400 nm) can cause serious and irreversible harm. Short-term overexposure can result in photokeratitis (arc eye), erythema (sunburn-like skin reactions) and corneal damage. Long-term effects include cataracts, skin ageing, and an elevated risk of skin cancer.

Many industrial and commercial UV applications produce significant levels of radiation, including UV-C germicidal disinfection systems, UV curing and bonding equipment, fluorescent inspection lamps, and certain welding processes. Workers operating, maintaining, or simply working in proximity to these sources may be at risk — often without realising it.

This is why a structured, evidence-based UV risk assessment is the cornerstone of your legal compliance programme.

The legal framework: CAOR 2010 and EU Directive 2006/25/EC

The Control of Artificial Optical Radiation at Work Regulations 2010 transpose EU Directive 2006/25/EC into UK law. Together, they establish a clear duty of care for employers who operate artificial light sources that emit optical radiation – including ultraviolet, visible, and infrared radiation.

For UV radiation, the regulations focus specifically on the 180 to 400 nm wavelength range – a span that covers UV-C (100–280 nm), UV-B (280–315 nm) and UV-A (315–400 nm). Each of these sub-bands carries distinct health risks and is subject to specific exposure limit values.

What employers are required to do

Under CAOR 2010, employers with UV light sources must:

• Identify all artificial UV light sources in the workplace
• Assess the risk of harm to employees from UV exposure
• Implement appropriate technical and administrative control measures
• Measure personal UV exposure levels and compare them against the statutory Exposure Limit Values (ELVs)
• Provide workers with information and training specific to the equipment, process, risks, and control measures in place
• Maintain documented evidence of compliance

It is worth emphasising that the regulations do not simply ask employers to consider whether UV poses a risk in general terms. They require actual exposure data, compared against legally defined limits, with documented evidence. This is a key point we return to below.

Understanding the UV Exposure Limit Values (ELVs)

The exposure limit values set out in Directive 2006/25/EC and CAOR 2010 define the maximum amount of UV radiation a worker may be exposed to in a working day (typically taken as an eight-hour shift). There are two separate limits, each applying to a different part of the UV spectrum:

The 30 J/m² (Effective) Limit

The first limit of 30 joules per square metre effective (J/m² eff) applies to all UV wavelengths from 180 – 400 nm. This is the limit most associated with eye and skin injury.

30 J/m² effective is a very small amount of energy. A powerful broadband or UV-C disinfection lamp can deliver this dose in seconds at close range.

The word ‘effective’ is important here. The limit is not based on raw UV intensity alone, but on radiation weighted according to its biological hazard — meaning different wavelengths are multiplied by a weighting factor that reflects how damaging they are to human tissue. This weighting process requires specialist knowledge and calibrated measurement equipment to apply correctly.

The 10,000 J/m² Limit

The second limit of 10,000 joules per square metre applies to UV-A radiation (315–400 nm). UV-A is less energetic than UV-B or UV-C, which is reflected in the much higher limit. However, it penetrates deeper into the eye and can contribute towards cataracts, so exposure needs to be limited.

10,000 J/m² is still not a large quantity of energy for high-intensity UV-A sources. Curing lamps, blacklight fluorescent tubes, and LED UV sources can produce significant UV-A output, and workers in close proximity to these sources over an extended period may approach or exceed this limit.

What you can (and cannot) do in-house

It is entirely reasonable for a competent health and safety professional to lead certain elements of the UV risk assessment process. The regulations do not require everything to be outsourced, and building internal understanding is good practice.

What can be done in-house

Many valuable preparatory steps can be completed internally:

• Identifying and listing all UV light sources on site
• Gathering equipment specifications and manufacturer data sheets
• Reviewing current control measures (guarding, enclosures, PPE, restricted access zones)
• Documenting operator roles, exposure patterns, and proximity to UV sources
• Identifying which workers may be at risk

What cannot be done without specialist support

However (and this point is critical) you cannot demonstrate compliance with the statutory ELVs without actual, measured exposure data. The regulations are explicit: employers must measure personal exposure and compare it to the limits. An assumption, estimate, or manufacturer’s claim is not a substitute.

Without this data, your risk assessment is incomplete. You may have excellent controls in place, but without measured evidence you cannot confirm (and document) that those controls are sufficient to keep exposure below the legal limits. This matters both for worker protection and for regulatory audit.

Specific information and training provided to workers must also be based on this data. Workers are entitled to know their actual exposure levels, the relevant limits, and the maximum safe exposure times or working distances applicable to their specific task and equipment.

The steps of a compliant UV risk sssessment

Step 1: Identify all UV light sources

Begin by conducting a thorough inventory of all UV-emitting equipment across your facilities. Include UV-C disinfection systems, curing and bonding lamps, fluorescent inspection equipment, UV LEDs, and any other sources emitting between 180 and 400 nm. Don’t forget maintenance activities, where workers may be exposed to UV sources during servicing or lamp replacement.

Step 2: Identify who may be exposed and how

For each source, consider who is exposed, how frequently, and for how long. Operators working directly with the equipment, maintenance engineers, and bystanders working in adjacent areas all need to be considered. The nature of the task (distance from the source, duration of exposure, whether the source is enclosed or open) all affect the level of risk.

Step 3: Review control measures

Assess the controls currently in place. These may include physical guarding and interlocks, administrative procedures (restricted access, permits to work), personal protective equipment such as UV-blocking eyewear and appropriate clothing, and warning signs and exclusion zones. Good controls reduce exposure, but as noted above, they cannot be assumed to reduce it below the ELVs without measurement.

Step 4: Measure personal UV exposure

This is the step that requires specialist equipment and expertise. Personal UV exposure must be measured using calibrated, spectrally-weighted radiometers capable of assessing radiation across the relevant parts of the 180–400 nm range. The results are then processed using the appropriate biological weighting functions and compared against the relevant ELV.

This is not a task for a standard UV irradiance meter or industrial hygiene instrument. Only purpose-designed UV measurement instruments, operated by someone who understands the weighting methodology, will give you legally defensible results.

Step 5: Compare against the ELVs and document the outcome

Once exposure data is available, compare it against the 30 J/m² effective limit (180 – 400 nm) and the 10,000 J/m² limit (315 – 400 nm). Document the findings clearly, including the measurement methodology, equipment used, results, comparison with ELVs, and any recommendations for further controls.

Step 6: Provide information and training to workers

This is a specific legal requirement – not a general awareness exercise. The training provided to workers must be specific to the equipment they use, the processes they carry out, the control measures in place, and the actual exposure levels measured. Workers must understand their entitlement to health surveillance and how to report adverse health effects.

Worker training: A specific legal obligation

One element of the regulations that is frequently overlooked is the requirement for specific, tailored training for employees who work with or near UV light sources. This is not satisfied by a generic UV awareness video or a brief induction note. The regulations require information and training that is relevant to the individual worker’s role, equipment and exposure.

Specifically, workers must be informed of:

• The type and wavelengths of UV light they are exposed to
• The potential short and long-term health effects of that exposure
• The control measures in place and how to use them correctly
• The maximum safe exposure times or safe working distances applicable to their task
• Their entitlement to health surveillance
• How to recognise and report symptoms of overexposure

This last point reinforces why exposure measurement must come first. The training content (particularly safe working distances and maximum exposure durations) can only be defined accurately once you have the measured data. Training delivered before measurement is incomplete and potentially misleading.

Common gaps in UV risk assessments

Based on experience assessing UV equipment across a wide range of sectors, the most common compliance gaps include:

• Risk assessments completed without any measured exposure data
• Generic hazard information provided to workers rather than process-specific training
• PPE specified without evidence that it reduces exposure below the ELV
• Assumptions that enclosed or interlocked equipment requires no further assessment
• Failure to assess maintenance and servicing activities, where UV sources may be accessed directly
• No consideration of UV-A exposure from curing or inspection lamps, which can be significant

Each of these gaps represents not only a compliance risk but a genuine risk to worker health, and a potential liability for employers in the event of an injury or regulatory investigation.

Getting your UV risk assessment right

A compliant UV risk assessment is not a single document, it is a structured process that combines internal knowledge of your processes, specialist measurement expertise, and properly documented evidence. The good news is that with the right support, the process is straightforward to manage and can typically be completed in a single coordinated engagement.

Arden Ultraviolet provides a complete UV safety and compliance programme designed to take organisations from initial assessment through to full documented compliance. Our structured approach includes:

• UV Risk Management Training for your safety team
• Onsite measurement and assessment of UV exposure for each process
• Tailored UV Hazard Awareness Training for your employees

Summary: Key takeaways for health and safety professionals

• CAOR 2010 and EU Directive 2006/25/EC require employers to assess and control UV exposure for workers exposed to artificial UV sources in the 180–400 nm range
• Two ELVs apply: 30 J/m² effective and 10,000 J/m² per working day
• Calculating exposure against these limits requires specialist equipment, calibrated instruments, and knowledge of spectral weighting – this cannot reliably be done in-house
• Preparatory work such as source identification and control measure review can be completed internally, but compliance cannot be confirmed without actual measured data
• Worker training must be specific to the equipment, process, control measures, and measured exposure levels – generic training does not satisfy the regulations
• A complete UV risk assessment includes identification, measurement, documentation, and tailored employee training