Setting the Standard: Leading Industry Guidance on Air Quality Monitoring

Sarah Horrocks, Head of Air Quality and Emissions at AtkinsRéalis in the UK, has spearheaded the development of a good practice guide to monitoring air quality at brownfield sites for the Institute of Air Quality Management (IAQM), part of the Institution of Environmental Sciences (IES). As lead author and chair of the working group - comprising both air quality and land contamination specialists - she explains how this guidance was established and why it matters for the sector.

 When redeveloping brownfield or former industrial sites in urban settings, the need to consider the health impacts of odours and the need for robust air quality management and monitoring strategy can be overlooked during the remediation phase. Existing regulations and guidance cover combustion emissions and construction dust, however there has historically been no clear framework for monitoring emissions during site clean-up stage, particularly for volatile organic compounds (VOCs) and odours.

That new IAQM guidance fills this gap, providing the first comprehensive good practice document for consultants, contractors or regulators involved in remediation projects. It aims to improve collaboration between air quality, contaminated land, and planning disciplines, ensuring monitoring strategies are consistent, risk-based, and proactive.

The Challenge: A Missing Framework

This initiative originated from experience on a major redevelopment of a large, former gasworks site in West London. Community concerns about odours and potential health risks during remediation, including on-site soil treatment, were difficult to address in the absence of specific monitoring guidance.

Although monitoring data indicated that direct health risks were not significant, Public Health England (now UK Health Security Agency) advised that exposure to odours and associated indirect psychological effects of this was undesirable.

This highlighted a critical issue: remediation phase emissions often fall between occupational health guidelines, contaminated land regulations and local air quality standards. Contractors typically monitor occupational exposure to total VOCs, but these measures do not account for long-term public health impacts or community response to odours at much lower levels.

A structured, proactive approach was clearly needed - one that could be embedded at the planning stage, rather than reliance on reactive complaints handling mid-project.

Creating the Guidance

With the backing of IAQM we convened a working group to consolidate the fragmented advice from existing documents and practical insights from working on complex remediation projects.  The result is a coherent road map for local authorities, developers, and consultants covering:

• Planning Requirements: Key considerations for assessments and planning conditions for brownfield remediation.
• Monitoring Protocols: How and where to monitor emissions, ensuring data reflects public exposure, amenity and- occupational health.
• Interpretation Frameworks: Criteria for assessing results against suitable health-based standards and guidance on reporting styles.
• Community Engagement: The importance of early consultation, clear communication about odours versus health, and transparent data sharing.

The guide is non prescriptive – a wide range of brownfield sites may be encountered - but offers practical examples such as traffic-light systems for mitigation triggers, to help stakeholders anticipate and manage issues before they escalate. It does not cover dust, which is addressed in separate IAQM guidance.

Industry Impact

 This publication marks a significant milestone as for the first time, the sector has a single reference document for how to approach air quality monitoring during remediation. Developers benefit from clarity and consistency, reducing planning uncertainty and avoiding costly delays caused by poor communication. Local authorities gain a practical tool to safeguard public health and manage expectations and, most importantly, communities benefit from proactive engagement and transparent monitoring commitments.

Since its inception, the guidance has influenced remediation site practice and lessons learned from early projects have prompted major developers to adopt more comprehensive strategies across multiple sites. While case studies in the guidance focus on gasworks, the principles apply broadly from landfills to other industrial redevelopments, ensuring the guidance has far reaching impact.

Looking Ahead

 The ultimate aim of the guidance is for air quality and public health considerations to be become standard practice before and during remediation, fostering collaboration rather than conflict.

Consistency and clarity are key. If local authorities and developers agree robust monitoring commitments at the planning stage, and communities are engaged from the outset, any complaints can be better addressed with the thorough dataset and evidence trail.

By turning hard-earned lessons into actionable guidance this work not only fills a regulatory gap but sets a benchmark for responsible redevelopment, ensuring that as cities regenerate, they do so with transparency, accountability, and respect for the communities they serve.

Download the IAQM guide here