Overview

Air Dispersion Modelling (ADM) is a critical component of environmental and regulatory studies, used to predict the spread and concentration of airborne pollutants from industrial activities.

PNA Risk Management provides DOE-compliant air dispersion modelling services to support Environmental Impact Assessments (EIA), Detailed EIA (DEIA), and regulatory submissions. Our studies ensure emissions are properly assessed against Malaysian air quality standards and regulatory expectations.

Our Approach

We apply scientifically validated modelling techniques to simulate pollutant dispersion under site-specific conditions, including:

• Emission source characteristics (stack, fugitive, and area sources)
• Local meteorological conditions (wind speed, direction, stability class)
• Terrain and land use effects
• Building downwash and site layout

Modelling Capabilities

• Industrial stack emission modelling
• Fugitive and area source dispersion
• Flare and vent release assessment
• Odour dispersion studies
• Toxic gas dispersion (integration with QRA studies)

We utilise internationally recognised models such as:

• AERMOD – for regulatory compliance and near-field impact
• CALPUFF – for complex terrain and long-range transport

Regulatory Compliance

Our studies are conducted in accordance with:
– Environmental Quality Act 1974
– DOE Air Quality Modelling Guidelines
– Malaysian Ambient Air Quality Standards (MAAQS)

This ensures that all modelling outputs are defensible, auditable, and aligned with regulatory approval requirements.

Key Deliverables

• Ground-level concentration contour plots
• Identification of sensitive receptors
• Compliance assessment against air quality limits
• Cumulative impact assessment (existing + proposed sources)
• Technical reports suitable for DOE submission

Applications

• Environmental Impact Assessment (EIA / DEIA)
• Industrial plant siting and expansion
• Petrochemical and chemical facilities
• Power generation and utilities
• Support for CIMAH and QRA studies

Why PNA Risk Management

• Strong integration with QRA, consequence modelling, and CIMAH studies
• Deep understanding of DOE regulatory expectations in Malaysia
• Proven ability to deliver approval-ready technical reports
• Practical, solution-oriented recommendations for clients