Transport Scotland - LED trunk road lighting compliance information: EIR release

Information requested

I am writing to request information under the Environmental Information (Scotland) Regulations 2004 regarding the basis on which compliance with lighting standards is relied upon to demonstrate the safety of LED lighting used on the trunk road network.

In previous responses, it has been indicated that LED lighting is considered acceptable and safe through adherence to relevant standards (for example, engineering and electrical standards such as BS EN 13201 Road Lighting Standard and associated compliance frameworks).

To better understand the evidential and decision-making basis for this position, I request the following recorded information:

1. Evidence Supporting Reliance on Standards

Any recorded information which demonstrates or evaluates the assumption that compliance with lighting standards is sufficient to ensure:

• protection of human health (including long-term exposure considerations)
• protection of the environment (including light pollution and ecological impacts)

This may include (but is not limited to):

• internal assessments
• technical reports
• risk evaluations
• correspondence or briefings

2. Scope and Interpretation of Standards

Any recorded information setting out:

• how the scope and limitations of lighting standards have been interpreted in relation to:
  human health impacts
  circadian rhythm or biological effects
  environmental exposure
• whether the standards relied upon were assessed as addressing these factors directly or indirectly

3. Gap Analysis or Limitations

Any recorded information identifying:

• known limitations, uncertainties, or gaps in the standards relied upon
• whether any consideration has been given to areas not explicitly covered by those standards (e.g. long-term exposure, spectral composition, or cumulative effects)

4. Decision-Making and Risk Ownership

Any recorded information which identifies:

• which organisation or body is responsible for assessing health and environmental risks associated with LED lighting
• how responsibility is allocated where reliance is placed on external standards or third-party guidance
• any documented rationale for not undertaking independent assessments where standards are relied upon

5. Use of External Advice or Evidence

Any recorded information showing whether reliance on standards has been informed by advice or evidence from:

• Public Health Scotland
• UK Health Security Agency
• International Commission on Non-Ionizing Radiation Protection
• Scientific Committee on Health, Environmental and Emerging Risks

including any correspondence, briefings, or internal summaries of such advice.

6. Post-Implementation Verification

Any recorded information relating to:

• whether the assumption that “standards compliance ensures safety” has been verified in practice
• any monitoring, evaluation, or review undertaken after LED lighting deployment

7. Clarification Where No Information Is Held

If no information is held in relation to any of the above, please confirm this explicitly.
In particular, please confirm whether:

• no assessment has been undertaken to verify that compliance with standards is sufficient to address health or environmental impacts; and
• no recorded evidence exists supporting the assumption that such standards fully address these risks.

To assist with proportionality, I would be content for responses to focus on:

• a representative policy position; or
• a defined sample scheme or programme area

rather than requiring a comprehensive review of all records.

Response

On 20 April 2026 you confirmed by email you were not seeking a restatement of previous responses, but rather recorded information demonstrating how the sufficiency of standards has been determined.

In response to your questions 1 through 6, Transport Scotland or its operational partners do not hold any recorded information, further to that which has been issued to you already through previous EIRs, relating to:

1. Evidence Supporting Reliance on Standards
2. Scope and Interpretation of Standards
3. Gap Analysis or Limitations
4. Decision-Making and Risk Ownership
5. Use of External Advice or Evidence
6. Post-Implementation Verification

Transport Scotland’s role is to ensure the application and adherence to the lighting standards in the design and implementation of Trunk Road and Motorway lighting. The British Standards Institution, lighting industry bodies, and other European organisations which set these standards have done so with due cognisance of the issues you highlight.

I refer to our previous EIR responses (202600505398 & 202500494567 & 202500486168) which detail the relevant industry bodies responsible for the assessment and setting of standards including, as follows:

·European Commission Scientific committee
·National Highways
·British Standards Institute
·Institution of Lighting Professionals
·Health and Safety Executive.

It is not the role of Transport Scotland to assess or challenge these standards as they are nationally recognised documents. Any concerns about their validity or scrutiny should be addressed to the relevant organisation directly. Contact information on these organisations was previously supplied in the response to enquiry Ref: 202600505398.

Regarding your enquiry: Under the terms of the exception at regulation 10(4)(a) of the EIRs Transport Scotland is not required to provide information which it does not have. Transport Scotland does not have the information you have requested because it is not responsible for this, however, the UK Health Security Agency may hold information on LED lighting that could provide some of the information you are looking for. You can contact them here: UK Health Security Agency | Contact us General enquiries: Enquiries@ukhsa.gov.uk Research enquiries: Research.Support@ukhsa.gov.uk

This exception is subject to the 'public interest test'. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. While we recognise that there may be some public interest in information about evidence supporting reliance on standards for protection of the environment, clearly we cannot provide information which we do not hold.

In response to your question 7, Transport Scotland can confirm that it has not undertaken any assessment to verify that compliance with standards is sufficient to address health or environmental impacts. It should be noted that this is not a position specific to road lighting or Transport Scotland, and that adherence to set standards is normal practice across roads and other industries, with specific standards setting bodies responsible for the suitability of standards to be applied.

As such, Transport Scotland can confirm no recorded evidence is held supporting the assumption that such standards fully address these risks.

I would like once again to extend my offer of a meeting to discuss any of your questions further, to allow us to fully understand your needs around this subject matter, and to help us conclude with responses to your satisfaction. I will continue to assist, however it is important to understand what Transport Scotland and its operational partners roles are in relation to the setting, application, and assessment of the suitability of the lighting standards, and therefore the limitations on us in providing what you ask for.

About FOI

The Scottish Government is committed to publishing all information released in response to Freedom of Information requests. View all FOI responses at https://www.gov.scot/foi-responses.