Bioaerosol Assessment

Question: What is a Bioaerosol Assessment?

Answer: A Bioaerosol Assessment evaluates the risk to human health from airborne micro-organisms and biological particles, such as bacteria, fungi and endotoxins, released by certain processes. The most common sources are composting facilities, anaerobic digestion plants, waste transfer stations, material recycling facilities and some agricultural and wastewater operations.

The assessment predicts or measures bioaerosol concentrations at sensitive receptors and compares them with recognised acceptable levels. It is commonly required to support planning applications and environmental permit applications for waste facilities, and where new housing is proposed near an existing facility.

Question: When is a Bioaerosol Assessment required?

Answer: The Environment Agency requires a site-specific bioaerosol risk assessment for composting and similar biowaste facilities located within 250 metres of a sensitive receptor, such as a dwelling or workplace. Local Planning Authorities may also request an assessment for:

• New or expanded composting and anaerobic digestion facilities
• Waste and recycling operations handling organic material
• Residential or commercial development within 250 metres of an existing biowaste facility
• Facilities subject to complaints or permit review

The assessment demonstrates that the operation will not pose an unacceptable risk to health.

Question: What guidance is used for bioaerosol assessments?

Answer: Bioaerosol assessments in the UK are typically undertaken in accordance with:

• Environment Agency guidance on composting and bioaerosol risk assessment
• Association for Organics Recycling (AfOR) monitoring protocol
• IAQM Guidance on Monitoring in the Vicinity of Composting Facilities
• Environment Agency M9 and related monitoring guidance
• Environmental Permitting Regulations 2016 requirements

The Environment Agency’s acceptable levels are typically 1,000 cfu/m³ for total bacteria and Aspergillus fumigatus and 300 cfu/m³ for gram-negative bacteria at the sensitive receptor.

Question: What does a Bioaerosol Assessment include?

Answer: A typical assessment includes:

• Identification of bioaerosol sources and release mechanisms
• Identification of sensitive receptors within the study area
• Review of site operations and control measures
• Baseline bioaerosol monitoring where appropriate
• Predictive risk assessment or dispersion modelling
• Comparison with Environment Agency acceptable levels
• Recommendations for mitigation and ongoing monitoring

The assessment gives regulators and planning officers confidence that risks have been properly considered.

Question: How is bioaerosol monitoring carried out?

Answer: Bioaerosol monitoring uses calibrated air samplers, such as Andersen impactors or filter-based samplers, positioned upwind and downwind of the source and at sensitive receptors. Samples are cultured and analysed by a specialist laboratory to determine concentrations of total bacteria, gram-negative bacteria and Aspergillus fumigatus.

Monitoring is undertaken during representative operating conditions, such as turning or screening of compost, and is repeated periodically as required by the environmental permit.

Question: What mitigation can reduce bioaerosol risk?

Answer: Mitigation measures may include enclosing processes within buildings, using negative-pressure ventilation with biofiltration, misting systems, scheduling high-release activities to avoid unfavourable wind conditions, increasing separation distances and improving site management procedures. The assessment identifies the combination of measures needed to achieve acceptable concentrations at receptors.

Question: Why choose Syntegra Group for a Bioaerosol Assessment?

Answer: Syntegra Group provides bioaerosol risk assessments and monitoring for waste, agricultural and industrial operators and for developers proposing new uses near existing facilities. Our air quality consultants work to Environment Agency and IAQM guidance and coordinate closely with our odour, dust and dispersion modelling services so that a single, coherent assessment can be submitted for planning and permitting purposes.

We provide practical, clearly presented reports that satisfy regulators while supporting the operational needs of our clients.