FIRE AND EXPLOSION RISK ASSESSMENT (FERA)
The primary purposes of a FERA study are as follows:
- Identify fire and explosion hazards on the facility that may pose a risk to personnel, affect the facility equipment and may escalate to other parts of the facility;
- Quantification of fire and explosion risks arising from loss of containment;
- To determine the acceptability of the calculated fire and explosion risk at the facilities and identification of the key fire and explosion risk contributors. Risk contributors need to be identified by source and location;
- Assess the benefit of existing and possible, inherently safe, prevention, detection, control and mitigation measures for identified fire and explosion scenarios;
- Comparing fire and explosion risks of the design options being considered. This helps identifying design options with low risk, and selecting the option which is best from a risk
- For a Brownfield project the purpose of the FERA is to assess the new fire and explosion risks due to plant modification and to arrive at the cumulative risk of the new and existing facilities. In such a project the risk from the new facilities will not be assessed separately, it will be assessed in relation to the existing risk at the facility, and in particular the process facilities adjoining to the new facilities;
- To provide clear and unambiguous recommendations for risk reduction where necessary, to ensure that the facilities fire and explosion risks are controlled within acceptable limits.
The FERA Process flowchart is used as a framework for this guideline and to serve as a basis for the minimum requirement for a FERA study undertaken by a FERA specialist.
The FERA process essentially consists of;
- Identification of events which could cause fires or explosions;
- Analysis of frequencies of these events based on generic failure data;
- Modelling of event consequences, in terms of fire size, explosion damage and subsequent escalation;
- Recommending suitable means of preventing, detecting, controlling and mitigating fire and explosion events.
The FERA considers accidental releases from equipment’s carrying flammable & hazardous inventory. Normal design operation of the isolation system is assumed when determining the duration and characteristics of releases. Dust release rates and durations shall calculate based on normal operating pressures and process conditions.
The consequence analysis determines the size and duration of releases and predicts hazard zones for releases in terms of radiant heat. FERA evaluates the adequacy of fire protection system and recommends risk reduction measures based on the consequence results.