Who's Who

Post holders

Claire Holman
Claire Holman FIAQM


Claire Holman has worked on air quality for the past four decades since being awarded her PhD for research into ozone pollution in 1980. She is currently a director of Air Pollution Services, a specialist air quality consultancy, working on a range of Government Agency and other research projects, as well as overseeing air quality assessments for planning applications. She is a former chair of IAQM, and an experienced expert witness for planning inquiries and litigation.  She provided evidence on the government‘s lack of adequate policies to improve air quality at the inquest into the death of Ella Kissi-Debrah, on behalf of her family, and worked for ClientEarth on their successful challenges to the government’s Air Quality Plans. She also led the development of a number of IAQM guidance documents.

Chris Rush
Chris Rush MIAQM


Chris is a Consultant and Air Quality Group Lead at Hoare Lea. His diverse portfolio of experience includes air quality assessments on a range of projects from initial site feasibility, through planning and development to construction and operation. Along with work at the planning stage, including Environmental Impact Assessments, he has recently been involved in the testing and assessment of indoor air quality (IAQ) and furthering understanding of how building design contributes to IAQ in the detailed design stages and operation. He has previously been closely involved with the IAQM Early Career Group Committee and organising a number of well-attended discussion meetings in Manchester. He is a Chartered Environmentalist and has an MSc in Air Pollution Management and Control.

Kieran Laxen
Kieran Laxen MIAQM

Vice Chair

Kieran is the Vice-Chair of IAQM and is a Director at Air Pollution Services. Kieran has over eleven years’ experience in the field of air quality. He has extensive experience of air quality assessments for residential and commercial developments, road schemes, waste management processes, industrial processes, power generation facilities, air quality monitoring and is a leading UK expert in the assessment of power generating facilities for both permitting and planning applications.

Xiangyu (Sian) Sheng MIAQM

Vice Chair

Dr Xiangyu (Sian) Sheng is a leading expert in Air Quality and Climate Change with over 25 years’ experience. She has wide range of expertise in air quality modelling, odour, climate change, whole life cycle carbon assessment for large infrastructure schemes and urban development. She is a Director at Temple Group. Previously she worked at Capita/GL Hearn, Scott Wilson and CERC etc. She has been a technical lead for numerous high profile projects e.g. HS2, TfL, London 2012 Olympic Legacy, Brent Cross, Crossrail, 2008 Beijing Olympic, EU LIEP, EU-EMCP and EU EGP. Dr Sheng is a Fellow of the Royal Meteorological Society (FRMets), a Chartered Engineer (CEng), a Chartered Physicist (CPhys), and a Chartered Environmentalist (CEnv). She is a member of IAQM. Dr Sheng holds a BSc, BEng, MSc, MPhil and PhD. She has over 40 journal and conference publications. She published a book ‘Air Dispersion Modelling in Regulatory Applications’ in 2005.

Honor Puciato
Honor Puciato MIAQM

Chair of the Early Careers Network Subcommittee

Honor is a Senior Consultant with over nine years of experience in public and private sectors, with a key focus on the Local Air Quality Management, the Environmental Impact Assessment (EIA) and Planning Process. Her work has covered a broad range of projects, including monitoring, evaluation of impacts from various local sources such as road traffic, on-site energy generation, odour and demolition and construction activities, as well as emission assessments and due diligence reviews of air quality reports and post-application advice. Outside work Honor is STEM Ambassador and a member of the Toastmaster International – Public Speaking Group, what shows her passion for effective communication and people engagement.

Ethny Childs


Ethny is Communities & Partnership Lead at the Institution of Environmental Sciences (IES). She is responsible for supporting the IES Communities and building relationships with partners and stakeholders in the sector. She is an ex officio member of the IAQM Committee and is the first point of call between the IES and IAQM. Ethny is a Trustee for Charityworks, sits on the SiLC Board and holds positions on the Steering Groups for the Professional Bodies Climate Action Charter, the Equator Programme and the Weston Communicating Climate Programme. Ethny has a BSc in Biological Sciences with Management from Imperial College London and has a keen interest in wildlife and environmental conservation. She completed the Charityworks Graduate Scheme with Commendations in 2018 and prior to this role worked for a medical research funding charity.

Other committee members

Jamie Clayton MIAQM

Jamie is an air quality consultant with approximately 15 years’ experience in the consultancy sector. Jamie has a wealth of expertise relating to air quality assessment for both public and private sector clients, linked to both road traffic, and industrial sources. He has assumed the role of lead developer of Defra’s Emissions Factors Toolkit since 2016, additionally he has project managed the UK Urban NO2 Network (UUNN) since network inception in 2020. Jamie has an MRes in Physics of the Earth and Atmosphere from the University of Leeds and is a Chartered Scientist (CSci). He has previously been involved in the IAQM Air Quality and Climate Change working group providing authorship to comment pieces as well as chairing group webinars.

Carl Hawkings
Carl Hawkings MIAQM

Carl started his working life at ERM in 1986 as an Ecologist. Sharing one of the few PCs in the London office with an air modeller he soon started helping out with modelling and air studies. He transferred to the air team between 1988-2000 when Carl joined ADM Ltd. Carl currently works with 3 main clients (Arup in the air quality team; Shell, in their major projects team and the World Bank in their Washington-based ombudsman team, as an air and EIA technical advisor). His air and EIA work involves him in many different sectors including transport, infrastructure, power, oil & gas, cement and incineration. He has worked in over 40 countries worldwide, most recently providing air quality management training in Iraq and managing EIAs in Nigeria, Qatar, UK offshore and Bangladesh. He managed the AQ team in Arup for a year during a staff leave of absence and has recent operational experience, covering for 4 months as the Environmental Manager on an oil seed rape plant in the UK. He has contributed to IAQM guidance and been a member since its formation.

Annie Danskin MIAQM

Annie Danskin has 24 years of experience in the field of air quality consultancy, project management, training and research and was awarded Chartered Environmentalist status in 2021. She has prepared expert witness reports and frequently presented at public consultation events, planning hearings and conferences/user group meetings. She has substantially contributed to the development of young graduates and professionals into Senior and Principal Consultants in small and large consultancies having previously worked at CERC, BMT Cordah, TSI Scotland and URS/AECOM. She is currently Head of Air Quality at ITPEnergised, based in Edinburgh.

Having started her career when air quality consultancy was in its infancy, she has applied the science, guidance and ever-advancing software tools to a wide range of increasingly complex and challenging air quality problems, developing innovative solutions and assessment methodologies for air quality assessments approved by local authorities and regulatory agencies including SEPA, the Environment Agency and most recently, the Civil Aviation Authority (CAA).

Sarah Horrocks MIAQM

After graduating from the University of Bristol with a degree in Chemistry, Sarah spent a year at NPL in the air quality standards team. After that she completed a Masters in Environmental Technology at Imperial College and subsequently found a job with Atkins. She is now the Practice Manager for Air Quality and recently celebrated 20 years at the company. As well as looking after and winning work for our 16 specialists, she is responsible for managing and delivering technical input to a wide range of markets: transportation, energy, water and land developments, in the UK and overseas. She is passionate about delivering high quality environmental work, and equally so about creating a working environment that is truly inclusive.

Christine McHugh photo
Christine McHugh MIAQM

Christine is an independent air quality consultant with over 25 years’ experience, working for Keane & Gray. She previously worked for Arup where she led the UK air quality team, Amec Foster Wheeler and CERC. She has particular expertise in air quality modelling, emissions, forecasting, and airport air quality, having led air quality studies for several major UK airports. She has provided planning and other technical support to the Greater London Authority leading a comparison of London’s air quality with cities around the world. Christine provided training and expertise internationally, as the EU expert on air quality in the EU/China Liaoning Integrated Environment Programme, on projects for the European Space Agency, EU 7th Framework, and the European Commission. She was elected Chair in 2019.

Daniel Marsh MIAQM

Daniel is part of the aerosol science team at the Environmental Research Group, Imperial College London, specialising in the control of dust and emissions from construction and demolition.

He is the programme manager for the Centre for Low Emission Construction, which aims to raise awareness of the air quality impacts from the construction industry, promote ‘best in class’ mitigation and emission reduction practices, and measure real-world emissions from construction machinery to enhance understanding, test the efficacy of reduction efforts and improve emission inventories. Daniel was the recipient of the 2016 Ian McCrae award for ‘Outstanding Work in Air Quality’.

Davide Pascarella MIAQM

Vice Chair of Early Career Network

Davide is leading the Air Quality team at the RSP (Regulatory Services Partnership) serving the London Boroughs of Merton, Richmond upon Thames, Wandsworth and has over 15 years of experience in public sector. He has expertise on the Local Air Quality Management, Policies and Regulations. His work has covered a broad range of projects, managing monitoring networks, demolition and construction activities, writing bidding proposals as well as experience on reviewing air quality assessment reports submitted as part of the planning process. He is a full member of the IAQM and has an MSc in Environmental Analysis and Assessment.

Philbert Chan MIAQM

Philbert is the Air Quality Lead at the Rail Safety and Standards Board (RSSB). He has over 15 years of experience working in the air quality industry. His current role is the key air quality expert within the rail industry, working with the Department for Transport (DfT) to provide support and advice on policies and strategies development, specifying research and implementation projects to improve understanding on GB Rail’s internal air quality issues, and assessment projects to investigate rail’s air quality impact on the ambient environment. Some key current projects include the development and operation of UK’s first Stations Air Quality Monitoring Network (AQMN) covering over 100 stations, establishment of rail specific Air Quality Targets, and further research into onboard trains air quality. Prior to his role at RSSB, Philbert worked as senior and principal consultants at different firms, and his last appointment being a senior consultant at Arup. He has expertise in carrying out dispersion modelling, setting up monitoring programme and developing emissions inventory. He worked on a range of projects including developemnts, highways, ports and power plants. He is a full member of the IAQM (MIAQM) and a Chartered Environmentalist (CEnv).

Bernard Fisher
Bernard Fisher MIAQM


Bernard Fisher is an environmental modeller with nearly 40 years research experience of air quality modelling. His career started in the power industry where he worked on acid rain. Between 1994 and 2000 he was Professor of Environmental Modelling at the University of Greenwich working on air quality management. Since joining the Environment Agency in 2000 he has been involved with the evaluation and use of environmental models with emphasis on air quality. He is a visiting professor at the University of Hertfordshire and a former Chair of the IAQM. He was elected the Institute’s first President in 2019.