Airborne Hazards Emergency Response (AHER)
What is AHER?
During major incidents, AHER ensures that we manage risks from air pollution in a comprehensive and expert-driven way. Under SEPA’s leadership, air quality, public health and food safety experts collaborate to form a well-rounded assessment and provide informed advice.
The Hertfordshire Oil Storage Terminal fire in 2005, also known as the Buncefield incident, highlighted the need for a specialised unit to coordinate the response to air pollution events like this. This led to the creation of the Air Quality Cell (AQC) for England and Wales followed by the Airborne Hazard Emergency Response (AHER) in Scotland.
How does AHER operate?
When a significant fire, chemical spill, or gas release happens, SEPA get notified via our pollution hotline by partner agencies such as the Scottish Fire and Rescue Service, site operators, or members of the public. One of our Air Hazard Advisors (AHAs) then conduct a risk assessment for the incident.
If there is a potentially significant risk to public health, the AHA collaborates with Public Health Scotland to assess the situation. If necessary, an Air Hazard Advice Cell (AHAC) will be established, and they may advise the need for air quality monitoring.
When a decision to monitor air quality is made, our field response teams are sent to a suitable location agreed upon by the AHAC. On site, the team use various instruments to monitor a wide range of gases and airborne pollutants. The information collected helps emergency services and other agencies to accurately assess the situation and make informed decisions to protect the public.
When a major incident threatens air quality, the emergency services provide advice to those most at risk. Their advice is to either shelter indoors with windows, vents and doors closed, or to evacuate. This advice is based on well-established understanding of the adverse health effects resulting from prolonged exposure to smoke and toxic gases.
The AHER field response team typically deploys to areas on the edge of the smoke or gas plume. This positioning allows them to determine the extent and possible movement of the plume and provide accurate safety information to individuals on the outside of the shelter or evacuate zone.
This approach ensures that the team can operate safely while providing essential information to the wider community who aren't subject to any specific shelter advice.
AHER was established to support public health advice in the event of major incidents involving industrial activities. It doesn’t deploy to certain air pollution events, including:
short-term incidents: Events expected to resolve within 1 to 2 days
natural events: Such as wildfires or volcanic ash clouds
occupational or regulatory: Monitoring related to workplace exposure or enforcement of environmental regulations
radiological, nuclear, biological: Events requiring specialist monitoring or advice
hostile incidents: Involving unidentified chemical agents with intent to harm
However, depending on the incident, we may opt to form an AHAC to provide technical or scientific advice in support of multi-agency response efforts.
Fortunately, AHER field response teams rarely need to deploy, but it is crucial that we stay well-practiced and prepared to act immediately. To ensure our operational readiness, we regularly test our systems and conduct both tabletop and live exercises.
In 2023, we were kindly given the opportunity to conduct an exercise at the state-of-the-art Scottish Fire and Rescue Service National Training Centre in Cambuslang, South Lanarkshire. This exercise aimed to mimic a significant petrochemical fire. The fire service’s Petrochemical Unit graciously provided our staff with an immersive and realistic experience. The day gave the staff involved a refresher in AHER procedures and equipment within a live, controlled fire environment.
The Scottish Fire and Rescue Service's generous cooperation in conducting this exercise highlights the importance of collaboration with our counterparts in other agencies. Although we lead AHER, its delivery would be impossible without our partners' support, and we are constantly striving to strengthen these relationships.
What is the Air Hazard Advice Cell (AHAC)?
The AHAC plays a key role in managing incidents with potential airborne hazards. It is a multi-agency group of experts in air quality, public health, food safety and weather modelling. Permanent members include:
Scottish Environment Protect Agency: Air quality and monitoring teams
Public Health Scotland: Environmental public health
Food Standards Scotland: Food safety
Met Office: Plume modelling and forecasting
In addition to the above agencies, the AHAC will seek to include representatives from the NHS Health Board and Local Authority in whose boundary the incident is occurring. The AHAC may also seek input from the Scottish Fire and Rescue Service, Health and Safety Laboratory, technical experts from the site involved and any others with relevant expertise.
The AHAC will assess the situation, determine monitoring requirements, review any data collected and prepare advice on protecting public health. This information is communicated to groups involved in the broader response efforts, such as the Scientific and Technical Advice Cell (STAC) and Resilience Partnership (RP).
Developing AHER
While our procedures and equipment are proven and reliable, we're continuing to invest in improving AHER's resilience and delivering the highest quality service. In the 2023 to 2024 financial year, we replaced aging AHER vehicles with modern, efficient alternatives and upgraded essential equipment to the latest models. This reflects our dedication to providing this service to the people of Scotland for years to come.
To develop AHER, we also monitor technological advancements that could enhance our delivery. We review cutting-edge equipment and approaches to air quality measurement, including enhancements in sensor technology.