Air Quality Dust Risk Assessment (AQDRA): What Construction Sites Need to Know

If you're planning construction, demolition, or major earthworks, you've probably been told you need an Air Quality Dust Risk Assessment. Commonly referred to as an AQDRA, this document has become a standard requirement for most development sites across the UK – and for good reason. Construction dust isn't just a nuisance; it affects public health, damages property, and can cause serious ecological harm if not properly controlled.

Getting the AQDRA right matters. A poor assessment will be challenged by planning officers, causing delays. An inadequate dust management approach can result in enforcement action, complaints from neighbours, and potentially legal action under nuisance legislation. This guide explains what an AQDRA actually involves, when you need one, and how to approach it properly.

What Is an Air Quality Dust Risk Assessment?

An AQDRA evaluates the risk of dust impacts from construction activities on surrounding areas and identifies appropriate mitigation measures. It assesses how dust generated by demolition, earthworks, construction, and vehicle movements ('trackout') might affect sensitive receptors – typically homes, schools, hospitals, shops, and ecological sites nearby.

The assessment follows a structured methodology developed by the Institute of Air Quality Management (IAQM), which provides a consistent framework used across the UK. The approach classifies sites into risk categories (low, medium, or high) and prescribes mitigation measures proportionate to that risk.

An AQDRA can be a standalone document or incorporated into an Air Quality Dust Management Plan (AQDMP). It may also form part of a wider Construction Environmental Management Plan (CEMP) or Environmental Impact Assessment (EIA).

Why Do You Need an AQDRA?

Dust from construction sites causes three main types of impact:

Annoyance and soiling – Dust deposits on cars, windows, gardens, and buildings. Even if not dangerous to health, this causes significant nuisance and frequently leads to complaints. Very high soiling levels can also damage plants and affect ecosystem diversity.

Human health effects – Construction activities increase concentrations of fine particulate matter (PM₁₀ and PM₂.₅). Long-term exposure to these particles is associated with respiratory disease, cardiovascular problems, and premature death. There's increasing focus on PM₂.₅, with no known safe threshold below which health effects don't occur.

Ecological damage – Dust deposition on vegetation creates ecological stress within plant communities. Sensitive habitats and designated ecological sites are particularly vulnerable.

The Environmental Protection Act 1990 makes it an offence to cause statutory nuisance through dust emissions. Local planning authorities routinely require AQDRAs to discharge planning conditions, and the GLA mandates them for major developments in London. Getting it wrong isn't just a planning problem – it's a legal and reputational risk.

When Is an AQDRA Required?

Most construction sites require an AQDRA, but there's a screening process to determine whether a detailed assessment is necessary.

Screening criteria typically include:

• Major developments (10+ residential units or 1,000m²+ floor space)

• Sites within 350m of sensitive receptors

• Sites within or adjacent to Air Quality Management Areas (AQMAs)

• Developments involving significant earthworks, demolition, or construction traffic

• Projects requiring Environmental Impact Assessment

For minor works well away from receptors, a simplified approach may be acceptable, though you'd still need to document why a detailed assessment wasn't required. Most planning authorities in urban areas will expect a full AQDRA for anything beyond very small-scale development.

In London, the GLA's Supplementary Planning Guidance on dust control makes AQDRAs mandatory for all major developments. Other UK cities are increasingly adopting similar requirements.

The Four Construction Activities Assessed

The IAQM methodology divides construction impacts into four categories, each assessed separately:

1. Demolition

Covers all activities involved with removing existing structures. Includes building demolition, deconstruction, site clearance, and crushing of materials on site. Demolition typically generates the most dust per unit of activity, particularly when buildings are knocked down rather than carefully dismantled.

2. Earthworks

Includes soil stripping, ground levelling, excavation, landscaping, and movement of materials around the site. The volume of material moved and the moisture content of soils significantly affect dust generation. Dry, fine soils in windy conditions create the highest risk.

3. Construction

Covers all activities involved with providing new structures – building construction, road construction, use of concrete batching plants on site, and similar activities. Generally produces less dust than demolition or earthworks, but still requires assessment, particularly for large-scale developments.

4. Trackout

The transport of dust and dirt from the site onto public roads by vehicles. Mud on wheels dries and creates dust emissions at considerable distance from the originating site. Track out can be the dominant source of dust impacts, particularly on sites with heavy vehicle movements and inadequate wheel washing.

The AQDRA Five-Step Process

The IAQM guidance sets out a clear five-step process for dust assessment:

Step 1: Screen the Need for Detailed Assessment

Determine whether the development requires a full AQDRA. Consider site size, proximity to receptors, activities involved, and local air quality. If screening indicates negligible risk, a detailed assessment may not be required, though you need to document the reasoning.

For most developments in urban areas, you'll proceed to a full assessment. Don't skip this step without properly documenting why – planning officers will challenge inadequate screening.

Step 2: Assess the Risk of Dust Impacts

This is the core of the AQDRA. For each of the four activities, you assess:

Dust emission magnitude – How much dust is the activity likely to generate? Classified as small, medium, or large based on factors like building volume (for demolition), area of site (for earthworks and construction), and number of vehicle movements (for trackout).

Sensitivity of the area – How sensitive are nearby receptors to dust impacts? Consider distance from the site, number of receptors, existing air quality, and specific sensitivities. Hospitals, schools, and care homes are particularly sensitive. Assess sensitivity separately for dust soiling, human health effects, and ecological impacts.

Risk level – Combine emission magnitude and area sensitivity using matrices in the IAQM guidance to determine risk for each activity and impact type. Risks are classified as negligible, low, medium, or high.

The assessment requires professional judgement. Every site is different, and you need to justify your classifications with reference to site-specific factors. Unjustified assumptions will be challenged.

Step 3: Determine Site-Specific Mitigation

Based on the risk levels identified in Step 2, specify mitigation measures from the IAQM guidance appropriate to each risk category. Mitigation is divided into:

• General measures applicable to all sites

• Specific measures for demolition, earthworks, construction, and trackout

• Highly recommended measures for high-risk sites

• Desirable measures for medium-risk sites

Higher-risk activities require more stringent controls. For high-risk sites, virtually all available mitigation should be implemented. For low-risk sites, basic best practice may suffice.

Mitigation measures range from simple housekeeping (damping down, covering materials) to more sophisticated controls (real-time dust monitoring, optimised site layout, wheel-washing systems).

Step 4: Determine Significant Effects

With appropriate mitigation in place, assess whether significant residual effects remain. The IAQM guidance states that with suitable mitigation applied, the residual effects of construction dust will normally be "not significant."

However, you need to demonstrate that mitigation is adequate and will be properly implemented and maintained. Don't just list generic measures – explain how they'll be applied to your specific site and how compliance will be monitored and enforced.

Step 5: Prepare the Dust Assessment Report

Document the entire assessment process clearly. The report should include:

• Site description and surrounding area

• Details of construction activities and phasing

• Baseline air quality and meteorology

• Identification and sensitivity of receptors

• Assessment of dust emission magnitude

• Risk matrices for each activity and impact type

• Specified mitigation measures

• Assessment of residual effects

• Responsibilities for implementation and monitoring

The report needs to be comprehensible to non-specialists while being technically robust. Planning officers, environmental health practitioners, and potentially members of the public will read it.

Key Risk Factors That Increase AQDRA Complexity

Certain site characteristics make dust assessment more challenging:

Proximity to sensitive receptors – Sites immediately adjacent to homes, schools, or hospitals require particularly careful assessment. Distance is the most important factor affecting dust impact. Most dust deposits within 100m of sources, though track out can carry dust much further.

Poor existing air quality – Sites in AQMAs or areas already exceeding air quality objectives need stricter controls. Adding construction dust to areas with existing PM₁₀ or NO₂ exceedances compounds public health impacts.

Large-scale demolition – Demolishing substantial buildings, particularly in confined urban sites, creates high dust risks. Tall buildings being demolished are particularly problematic as dust is released at height where wind can carry it further.

Dry, fine soils – Earthworks in sandy or silty soils during dry weather produce significantly more dust than clay soils or works during wet conditions. Soil type and moisture content are critical factors.

Heavy construction traffic – Sites generating large numbers of HGV movements, particularly if routes pass residential areas, create significant trackout risk. This is often the hardest impact to control effectively.

Long construction duration – Multi-year construction programmes mean receptors experience prolonged exposure. This increases the likelihood of impacts and the importance of sustained mitigation.

Common AQDRA Mistakes

Several errors frequently appear in poor-quality AQDRAs:

Inadequate receptor identification – Missing nearby sensitive receptors or incorrectly assessing their distance from dust sources. You need site surveys, not just desk studies, to identify all relevant receptors properly.

Underestimating dust emission magnitude – Optimistic assumptions about scale of activities or effectiveness of natural mitigation. Be realistic about what will happen on site, not what you'd like to happen.

Generic mitigation – Copy-pasting standard mitigation lists without demonstrating how they'll be applied to the specific site. Generic AQDRAs are easy to spot and will be rejected.

Ignoring cumulative impacts – Failing to consider other nearby construction sites operating simultaneously. In areas with multiple developments, cumulative dust impacts can be significant even if individual sites have moderate emissions.

Poor understanding of trackout – Underestimating distance that trackout affects or assuming wheel washing eliminates the problem. Track out is particularly difficult to control and often generates more complaints than on-site dust.

Inadequate professional input – AQDRAs prepared by people without proper air quality expertise. This is specialist work requiring understanding of dispersion, meteorology, exposure assessment, and regulatory frameworks.

The AQDMP: From Assessment to Management

An Air Quality Dust Management Plan (AQDMP) takes the AQDRA and translates it into practical operational procedures. While an AQDRA identifies risks and specifies mitigation, an AQDMP explains exactly how mitigation will be implemented, monitored, and enforced throughout construction.

A comprehensive AQDMP typically includes:

• Site management structure – Who's responsible for dust control, reporting lines, authority to stop work if necessary

• Training requirements – Ensuring all site staff understand dust risks and control measures

• Operational procedures – Specific instructions for each construction activity, tied to the mitigation identified in the AQDRA

• Monitoring and inspection – Visual inspection frequency, real-time monitoring equipment (if required), trigger levels for additional action

• Complaints procedure – How complaints will be recorded, investigated, and responded to

• Communication plan – How nearby residents will be kept informed, contact details for site management

• Record keeping – Documentation of mitigation implementation, monitoring results, complaints, and corrective actions

The AQDMP should be a living document, updated as construction progresses and reviewed regularly. Many planning conditions require it to be approved before works commence and mandate adherence throughout construction.

Real-Time Dust Monitoring

For medium and high-risk sites, particularly in sensitive locations, real-time dust monitoring is increasingly required. This involves installing PM₁₀ monitors at the site boundary that continuously measure particulate concentrations and trigger alerts when levels exceed predetermined thresholds.

The advantages are obvious – immediate warning when dust controls are inadequate, allowing rapid response before serious impacts occur or complaints arise. The equipment also provides objective evidence of dust control effectiveness, which is valuable if disputes arise.

The main requirement is that alerts go directly to site management with authority to take action. A monitoring system that records exceedances without anyone responding is pointless. Most systems now send automated SMS or email alerts to designated personnel.

Monitoring should commence before construction starts to establish baseline conditions. Continue throughout construction and for a period afterwards to demonstrate the site has been left in acceptable condition.

Non-Road Mobile Machinery (NRMM) Requirements

In London, all construction sites must comply with the Non-Road Mobile Machinery Low Emission Zone, which sets minimum emission standards for engines used on construction sites. This includes excavators, generators, compressors, and other mobile plant.

The requirements specify minimum engine emission standards that become progressively stricter over time. Equipment not meeting the standards cannot be used on London construction sites. This is an additional requirement to the AQDRA/AQDMP but is typically addressed within the dust management documentation.

Outside London, there's no formal NRMM Low Emission Zone, but specifying low-emission plant is increasingly standard practice and helps reduce both particulate and NOₓ emissions from construction sites.

Who Should Prepare an AQDRA?

AQDRAs require specialist air quality expertise. This isn't work for general environmental consultants without specific air quality qualifications and experience. The assessment involves technical judgements about emission rates, dispersion, exposure, and risk that require proper training.

Look for consultants who are members of the Institute of Air Quality Management (IAQM) and have demonstrable experience preparing construction dust assessments. Check examples of their previous work and confirm they understand local authority requirements in your area.

Poor-quality AQDRAs are false economy. They'll be rejected by planning officers, causing delays while you commission a proper assessment. Worse, inadequate dust control recommendations may lead to impacts during construction that could have been prevented.

The Planning Condition Problem

Most AQDRAs are required to discharge planning conditions. This creates a timing challenge – ideally you want the AQDRA completed early to inform site design and logistics planning, but detailed information about construction methodology often isn't available until contractors are appointed.

The pragmatic solution is a phased approach:

1. Outline AQDRA with planning application, based on indicative construction programme

2. Detailed AQDRA/AQDMP pre-commencement, once contractors appointed and methodology finalised

3. Updates during construction if activities or phasing change significantly

Make sure planning conditions allow this staged approach. Conditions requiring a complete AQDMP before any contractor appointment are problematic as you won't have the detailed information necessary for a site-specific plan.

Getting AQDRA Right

The key message is that AQDRAs aren't bureaucratic box-ticking – they're practical risk assessments that protect public health and prevent nuisance. Get them right, and construction proceeds smoothly with minimal complaints and no enforcement action. Get them wrong, and you face delays, additional costs, and potential legal problems.

Start early. Don't wait until pre-commencement conditions need discharging. Consider dust risks during site selection and early design. The best mitigation is often design-based – keeping dusty activities away from sensitive receptors, phasing work to avoid prolonged impacts, optimising site access to minimise trackout.

Engage competent air quality specialists. This is technical work requiring professional expertise. The cost of a proper AQDRA is minimal compared to construction costs and potential problems from inadequate dust control.

Think about implementation. The best AQDRA in the world is useless if mitigation isn't actually implemented on site. Make sure construction managers understand the requirements and have authority and resources to implement them. Include dust control in contracts with subcontractors.

Communicate with neighbours. Let people know what's happening, how long it will last, and what you're doing to control dust. Provide contact details for concerns. Most complaints come from people who feel ignored, not from dust impacts per se.

Remember that construction dust is largely predictable and controllable. With proper assessment, appropriate mitigation, and competent implementation, significant impacts can almost always be avoided. The AQDRA process gives you the framework to achieve that.