Air Quality Assessment: Construction

Demolition, remediation, site preparation and construction are phases that are easily overlooked during a development programme, as they generally represent a fraction of a scheme’s lifecycle.

If the potential effects on air quality of these phases are not effectively assessed and mitigated, then they can cause highly significant local effects. For the majority of construction projects, emissions of dust are the greatest concern in terms of air quality impacts.

Emissions of toxic gasses, vapours and fine particulate matter can also be significant, particularly on contaminated, brownfield sites. Consideration of construction phase effects is also a requirement of the Environmental Impact Assessment Regulations.

It is necessary to assess, model, predict and/or monitor emissions to the atmosphere during the phases of a development project before it is occupied and becomes operational.

In addition to the models and assessment tools used for industrial and vehicular emissions, as air quality assessment consultants, we have the capability to provide these additional air quality impact assessment services for a wide range of development projects.

Guidance published by the Institute of Air Quality Management separates emissions from construction activities into a number of distinct source groups or phases, which include:

• Demolition of existing structures
• Ground clearance and earthworks
• Construction of new structures
• Movements of vehicles and plant along access routes and soiled road surfaces.

There is also specific guidance for minerals works, which often use similar plant carrying out similar tasks to those associated with large construction earthworks.

Sensitive Receptors

Dust impacts on vegetation and ecologically sensitive areas also need to be considered. However, the lower sensitivity of such habitat usually makes it more resistant to the much lower concentrations and rates of deposited dusts that can potentially cause health impacts in humans or cause nuisance effects.

Transport Emissions Assessment & Consultancy

Emissions from road traffic are the most significant reason for the declaration of Air Quality Management Areas (AQMAs) by local authorities across the UK. This is usually due to housing being located close to roads in many urban areas.

For this reason, air quality strategy and management issues be a material consideration during the planning process. It is therefore often a requirement of the local planning authority that an air quality assessment should be undertaken for any development that proposes to either introduce sensitive receptors or to generate traffic to areas where air quality is a concern.

There are a variety of assessment tools that we use to assess the impacts on and sensitivities to various development proposals. These include screening tools developed from empirical relationships between traffic volume and distance of sensitive receptors from busy roads, to more complex computational dispersion models requiring detailed meteorological data as an input (e.g., Breeze Roads and ADMS Roads).

Typical projects that we have provided air quality assessments for include:

• Comparisons of proposed road scheme routes
• Residential developments
• Large mixed-use schemes
• Large commercial buildings
• Industrial estates
• Warehouses and distribution depots
• Retail developments
• Bus depots.

Phlorum’s Air Quality Assessment Methodology

The most common monitoring and assessment methods we use include the following:

• Monitoring of dust deposition rates and analysis of deposited dusts (e.g., morphological source apportionment analyses using scanning electron microscopy, x-ray microprobe analysis and spectrophotometry)
• Realtime sampling of airborne fine particulate matter (e.g., in the PM10, PM2.5 and PM1 size fractions)
• Pumped and passive sampling of speciated volatile organic compounds using sorbent media (e.g., Tenax and Sulphicarb tubes)
• Odour assessments, sampling and analysis (e.g., methodological ‘sniff-testing’ and collection of air samples for olfactometric analysis).

Contact our team of air quality assessment consultants today to discuss your needs for your upcoming construction project.