What is a lighting impact assessment?

A lighting impact assessment is an evaluation of the impact of proposed artificial lighting on an area surrounding a new development or construction project, or of the impact of existing artificial lighting on proposed sensitive receptors. The baseline lit environment is reviewed, determining whether existing or future human or ecological sensitive receptors will be impacted by the lighting design proposed as part of a planning application.

A lighting assessment must consider potential light pollution, the impact of artificial lighting on the light levels of the outdoor environment and any adverse effects of ecological factors, for example wildlife such as bats, and will normally be submitted as part of a planning application. At Miller Goodall, we specialise in providing lighting assessment for planning applications, but we can also provide services for other stages of development where required.

There are two types of lighting assessments, indoor and outdoor. At Miller Goodall we provide external environmental lighting impact assessments.


What types of developments require a lighting impact assessment?

A variety of industrial and commercial projects where significant external lighting is due to be installed. This includes leisure and recreation such as sports pitches and golf courses, retail parks, healthcare settings, schools, car parks, quarries and highway schemes.

A lighting impact assessment may also be required for residential-led developments, particularly for locations where there is a movement mix between people and vehicles, or areas where crime may be a material concern. Road lighting is needed in these areas and the effect of this is particularly important at speeds below and above 40 mph. Below 40 mph, illuminance (lux) is important to aid observations of conflicts and events such as movement of people and road junctions. Above 40 mph, luminance (reflectance of light from the road surface) is used as this provides improved road safety, identifying hazards over distance, greater light uniformity and lighting of the carriageway edges.

Lighting impact assessments are also carried out for residential developments that will be located close to sites with existing artificial lighting, for example a sports stadium or a retail park, or to establish the impact of a new housing development and any associated light pollution on its surroundings, for example if it is within or near to a conservation area or a listed building.

At Miller Goodall, our qualified lighting assessment consultants can carry out lighting assessments for a range of clients, such as developers, environmental consultants, highway engineers or local authorities. The main sectors we work across are ResidentialCommercialIndustrialAgriculturalTransportHealthcareSport and Entertainment, and Education.


How is light assessed?

Depending on the scale of the project, lighting assessments can be either desktop evaluations or research, for example using aerial photography, or may require a site visit. During a visit, a lighting assessment consultant will monitor existing light on the site under assessment by carrying out an illuminance survey of the area.  This involves taking a lux measurement – a unit of measurement which reflects the level of light illuminating a surface which correlates to human perception of light – at a number of locations and positions in and around the site.

The baseline environment is an important consideration to the assessment – is your development in a city, town outskirts or in a protected area of dark sky? This, along with other contributing factors, can then be assessed by producing a best practice light design meeting various planning regulations, guidance and British Standards.

All information gathered is finally compiled into a detailed lighting assessment report, containing findings and any recommendations which will help enhance and progress the project or development, ready to be submitted as part of the planning application. Our designs ensure appropriate column heights, styles, positioning, colour temperature, colour rendering and glare are accounted for following the core principle of right light, right time and right place. Models of the design and lux contour plots may be produced to provide visual illustration and proof of concept that the lighting design will not adversely affect the surrounding environment and demonstrate that sufficient lighting to relevant standards is met for the intended use of the development.

Lighting assessments are normally reviewed by local authority environmental health departments. These departments also review the acoustic and air quality disciplines. We are, therefore, well placed at Miller Goodall to provide multidisciplinary services, having built up an excellent reputation with various local authorities across the UK.


What information should be included in a lighting assessment report?

A comprehensive lighting assessment report needs to include factors such as:

  • A review of the baseline lit environment
  • Identification of sensitive receptors – human, ecology, environment (such as dark sky) and even buildings (such as conservation areas)
  • Details of the proposed hours of usage for the lighting, for example will lit signage in a large retail park remain on overnight, or do luminaires require continuous lighting to reduce crime and improve safety
  • A plan or model of the proposed development which visually reflects the impact of the lighting in terms of beam orientation, light spillage, glare, and sky glow
  • Recommendations for lighting, improvements or amendments to current proposals, in line with guidance from the Institution of Lighting Professionals (ILP), the Chartered Institution of Building Services (CIBSE) and the British Standard.
  • Identification of a lighting design and luminaires to be installed in the layout
  • A conclusion, summarising findings and recommendations

Whatever the reason behind your need for a lighting impact assessment, at Miller Goodall we have the expertise and experience to deliver the services required in an efficient manner and the right format, so your project can move along smoothly.

Bringing Miller Goodall into your project as your environmental consultant means you can be certain that you are meeting the required standards of environmental best practice. We carry out light assessments in locations across the UK and have consultants in the North West, North East and South West.

For more information on our lighting assessment service, please contact our team of experts today on

01204 596166 or info@millergoodall.co.uk.

We look forward to hearing from you.