8th CCPS Global Summit on Process Safety, Mumbai, India
The intent of Fire & Gas Detection System (FGDS) is to provide timely detection of any fire scenario or gas release and to raise alarms and/or initiate appropriate control action. The main purpose is to minimize catastrophic damage associated with escalation events due to undetected and thereby unmitigated fire/gas release scenarios. To ensure that the above objectives of the FGDS are achieved, a fire and gas layout is developed with the target equipment to be protected. However, there could be gaps in the target equipment considered for detector provision, reliance on conventional approaches for development of preliminary detector layout or in ensuring all hazards have been accounted for properly even when 3D Fire & Gas Mapping tools are used for the coverage assessment. Using practical examples and case studies (using 3D mapping tools), some of the key questions regarding FGDS will be reviewed and insights will be provided on best practices or way forward in maximizing the performance of FGDS. Some of these questions are:
- Which equipment should be provided with Fire and/or Gas detection?
- Process stream handles both flammable and toxic material, which type of detection should be provided? What to do when process streams handle both hydrogen and hydrocarbons or multiple toxic components?
- Can the same detector layout handle a change in voting logic i.e. 1ooN vs 2ooN?
- What parameters to select to best match actual detector performance? How to identify the optimal grade/area for detector coverage?
- Can detector layout from one project be used for another project if the facility type is same?
- Are risk based and scenario based approaches the same?
- How to ensure the credit taken for successful detection for activation of isolation and/or blowdown in risk assessment is matching the FGDS performance?
- When can CFD based gas detection study help?