Environmental Risk Assessment

Hazard-Based and Risk-Based ERA Studies

Arthian delivers both hazard-based and risk-based Environmental Risk Assessments (ERA) to help COMAH-regulated sites evaluate and manage environmental risks from major accident hazards.

 
Our approach supports regulatory compliance and environmental protection by:

 
• Identifying credible hazard scenarios and potential release pathways
• Assessing environmental consequences using both qualitative and quantitative methods
• Applying risk ranking to prioritise mitigation efforts
• Aligning with the CDOIF Guideline and COMAH safety report requirements

 
Whether for new developments or existing operations, our ERA studies provide clear, defensible evidence to demonstrate that environmental risks are reduced to ALARP.

Consequence Modelling (Overpressure, Thermal, Toxic Gas)

We use advanced consequence modelling tools to simulate environmental impacts from major accident hazards, supporting COMAH compliance and risk-based decision-making.

 
Our modelling covers:

 
• Overpressure effects from explosions and vessel ruptures
• Thermal radiation from fires and jet flames
• Toxic gas dispersion and receptor exposure

Risk Ranking and Mitigation Strategy

We assess and rank environmental risks from major accident hazards, helping COMAH sites prioritise threats and implement proportionate mitigation.

 
Our approach supports:

 
• Structured risk ranking using CDOIF tolerability criteria
• Development of targeted mitigation strategies to reduce environmental impact
• Improved regulatory defensibility for COMAH safety reports and permitting submissions

 
This ensures risks to environmental receptors are reduced to ALARP and managed consistently across high-hazard facilities.

Building Vulnerability Assessment

We assess the vulnerability of site infrastructure and occupied buildings to environmental hazards, helping COMAH sites strengthen resilience and reduce risk.

 
Our evaluations support:

 
• Identification of structural weaknesses and exposure to overpressure, thermal, or toxic hazards
• Assessment of building siting, occupancy, and protective features
• Integration with Environmental Risk Assessments and consequence modelling
• Alignment with COMAH safety reports and ALARP principles

 
This ensures buildings are appropriately protected and risks to environmental receptors are effectively managed.

Site-Wide Occupied Building Strategy

Our Environmental Risk Assessment (ERA) services support integrated, site-wide strategies for managing environmental risks to occupied buildings and sensitive receptors.
 
We help COMAH sites:

 
• Map environmental hazards relative to building locations and receptor zones
• Evaluate cumulative risks across multiple structures and operational areas
• Develop coordinated mitigation measures to reduce exposure and improve resilience
• Align with CDOIF guidance and COMAH safety report requirements

 
This holistic approach ensures consistent protection and regulatory defensibility across complex, high-hazard facilities.

Integration with COMAH, DSEAR and Permitting

Our Environmental Risk Assessment (ERA) outputs are designed to align with COMAH safety reports, DSEAR assessments, and environmental permitting requirements—ensuring consistent, defensible compliance across regulatory frameworks.
 
We support:

 
• Integration of ERA findings into COMAH safety documentation
• Alignment with DSEAR hazardous area classification and ignition risk controls
• Inclusion of environmental risk evidence in permitting submissions and impact assessments

 
This joined-up approach streamlines regulatory engagement and strengthens site-wide risk management.