Fire AND Gas Engineering

The Watchmen Fire & Gas Engineering services consulting team is focused on maximizing the effectiveness of Emergency Protection Systems used to prevent or mitigate the effects of major industrial accidents.  

Our team of experts apply their extensive expertise while leveraging advanced analytical software tools in our studies.  Our studies result in recommendations intended to maximize effectiveness of:

• ESD, Fire & Gas Protection Systems
• Emergency Annunciation / Notification Systems

Many serious industrial accidents have occurred in industry that may have been prevented or mitigated with an effective ESD, Fire & Gas detection and Annunciation system.  Early or incipient stage fires or gas releases without detection and mitigative action (such as emergency evacuation and automated process isolation) can escalate into large toxic gas releases or explosions with the potential for serious injuries/fatalities and economic loss.  So why have Emergency Protection Systems historically not been more effective in preventing or mitigating releases and/or fires from further escalation? The reason for this is that many of these systems are not properly designed, installed, commissioned, tested or maintained. These failures can be traced back to each phase of the safety lifecycle (design/specification, construction, commissioning, maintenance & operation, decommissioning). This understanding is ultimately what has led to the development of the Technical Report released by ISA (TR84.00.07) which provides a lifecycle management approach to performance based FGS implementation. With the largest percentage of failures identified as occurring in the design/specification phase, great emphasis should be placed on performing these activities well.  

Our team of highly trained specialists can inspect and evaluate existing installations against industry and corporate standards, best practices, and manufacturer recommended installation practices.  Drawing on our expertise with modelling many other detector applications, we are able to pick out potential impairments and misapplication of technology that could prevent the safe operation of fire and gas detection systems.

Ensuring proper Fire and Gas detector coverage can have the greatest overall effect on maximizing Fire and Gas System effectiveness.  Following ISA TR84.00.07 guidelines, our specialists perform a risk assessment to set application specific coverage targets.  This approach ensures a "fit for purpose" design by placing detectors where they are needed most.  Detector coverage is  optimized using a combination of qualitative and semi-quantitative approaches depending on complexity of the application.  For higher risk or complexity applications, we leverage 3D software to perform fire and gas detector coverage mapping.  We work with existing 3D files when available or develop new 3D files quickly and cost effectively.  The high level of accuracy that is possible with modelling enables the analyst to consider:

• Combining multiple technology options
• Brand specific detector field of view capabilities and limitations and sensitivity options
• Coverage impairments or obstructions 
• Effects of voting on coverage (i.e. 2ooN)
• Effects of changing detector elevations on coverage

The effectiveness of Fire and Gas Systems are affected by the reliability of the equipment used and by the voting configuration.  A reliability assessment can be performed to ensure the integrity of the system is maintained and is appropriate based on application specific risk.  This activity in the ISA TR84.00.07 standard is referred to as a Safety Availability assessment and is very similar to SIL verification calculations.  Watchmen can provide these reliability calculations as part of the FGS Effectiveness analysis particularly with reliability concerns from voting of fire and gas detection alarm actions.

•  Fire detectors cover open areas with no equipment, are installed too high to clean lenses without scaffolding or are obstructed by permanent or temporary equipment.  
• Gas detection placed without consideration of leak source locations or considering wind direction.  
• Excessive number of detectors compared to the risk.
• Improper technology or detectors in locations where fire or leak sources are not capable of activating the detector.  
• High risk areas with little to no detector coverage (i.e. 1-5% H2S process streams with no H2S detection in the area) or flame detectors monitoring the top of pipe racks with no view of the equipment below.
• Voting degrades coverage to the point that the fire or gas event must reach catastrophic levels before executive action is taken to mitigate the hazard.

 Annunciation equipment is a key component in evaluating the mitigative effectiveness of any fire and gas detection system.  The purpose of this equipment is to communicate the existence of an emergency situation to personnel that may be effected within the area.  Consequences can escalate quickly during an emergency if this safety critical equipment is not properly designed, installed, tested and maintained.  Our specialists can help with the initial placement and evaluation of existing installations to ensure proper coverage is in place.  We perform site surveys to map audible annunciation levels and compare to background sound levels to ensure proper audibility of annunciation equipment.   Our specialists can recommend audible and visual annunciation modifications in order to ensure emergencies can be communicated to those potentially affected by the hazard.

• Annunciation equipment is not operational, not tested regularly or not audible. 
• Horns cannot be heard above background noise.
• Emergency horns sound the same as non-emergency horns.
• The meaning of beacon colours or horn tones changes in different parts of the facility or in adjacent facilities causing confusion.
• Annunciation equipment is impaired by temporary equipment.