WHAT IS QUANTITATIVE RISK ASSESSMENT?
A Quantitative Risk Assessment (QRA) is a formal and systematic risk analysis approach to quantifying the risks associated with the operations of an engineering process. A QRA is an essential tool to support the understanding of exposure of risk to employees, the environment, company assets and its reputation.
WHY IS QUANTITATIVE RISK ASSESSMENT IMPORTANT?
With the risks associated with the establishment quantified through QRA, it helps organisations to make cost-effective decisions and manages the risks for the entire asset lifecycle. In many countries, it has been deemed mandatory by regulators and authorities to perform QRA as part of legal requirement.
In Singapore, QRA is set as a requirement by the following authorities:
- Ministry of Manpower (MOM): Under the Workplace Safety and Health (MHI) Regulations, Major Hazard Installations (MHIs) must submit Safety Cases where the QRA forms part of it.
- National Environmental Agency (NEA): Under the Development Control & Licensing Department (DCLD), for NEA license-related matters covering different areas such as radiation protection, pollution control, waste management, public cleansing and vector control, QRA may be required if deemed necessary for license application.
- Singapore Civil Defence Force (SCDF): Under the Fire Safety (Petroleum and Flammable Materials) Regulations, SCDF may request any new or existing premises undergoing modifications / expansions and transporting / handing / storing large quantities of petroleum and flammable materials to carry out a QRA study.
TÜV SÜD HELPS TO PERFORM COMPREHENSIVE QRA FOR YOUR FACILITIES
Being one of the approved QRA consultants in Singapore, TÜV SÜD stands apart from mainstream environmental advisories where we work closely with facilities owners and authorities. This position allows us to deliver unrivalled specialist commercial and technical focus. Our experts have experience from a wide range of projects, enabling us to identify risks and appropriate mitigation measures early in the development process. We draw upon our long-standing relationships with regulators and proven processes in coordinating multi-stakeholder dialogue to avert emerging problems and find suitable solutions for existing issues.
WHAT DO OUR QUANTITATIVE RISK ASSESSMENT SERVICES INVOLVE?
A QRA study comprises of the following steps:
- Hazard Identification
- Relevant data is gathered using the hazard review technique.
- Suitable study such as HAZID/HAZOP can be conducted to identify all possible accident scenario for the QRA.
- Major keywords such as fire, explosion etc. can help in identifying major accident scenarios.
- Identify Scenarios
- Generate a list of scenarios from the hazards identified
- Apply suitable screening methods when considering scenarios to be included in QRA
- Event Tree and Frequency Analysis
- Event tree: The event trees determine the outcome frequencies that will be input into the risk summation process
- Frequency analysis: By utilising suitable data sources and modifiers, the likelihood of failure of each scenario is determined as part of the QRA.
- Consequence Modelling
- Consequence modelling evaluates the resulting effects if the accidents occur, and their impact on personnel, equipment and structures, the environment or business.
- TÜV SÜD utilises industry standard software that is approved by authorities in Singapore for the consequences modelling. The outcome of modelling will define the harm distances and harm footprints required.
- QRA Results
- Consequence modeling results are interpreted in the form of toxicity, thermal loading (fire) or blast overpressure (explosion).
- Risk results are assessed in the form of Individual risk and shall be accounted for injury / fatality to people (onsite & offsite) as well as escalation off-site.
- ALARP Demonstration
- Appropriate controls (preventive or mitigation) shall be taken into consideration to keep the risk As Low as Reasonably Practicable (ALARP).
- The purpose of this approach is to identify potential improvements and/or to demonstrate that the risks associated with scenarios classified as “ALARP” are reduced as low as reasonably achievable from a technical point of view and economic.