Fire risk controls/control systems

Hot feed Provide and maintain an automated inerting (increases system—oxygen concentration or pressure fire/explosion risk controlled with flammable. Eliminate leakage sources (ftimes/air) solvents). Use alternative solvents (nonflammable or less flammable) Reduce feed temperature and/or monitor temperature of feed and interlock with feed shutdown NFPA 69... 

Risk Reduction Factors Coutrol/ rator responses. Alarms, Control system response. Manual anti automatic ESD, Fire/gas detection system Sa/ety System Responses Relief valves. Depressurization system. Isolation systems, High reliability trips. Back-up systems... 

These systems must be inherently reliable and safe, particularly from the point of view of fire protection, and fire-resistant fluids can be used for control systems in order to reduce this risk. Fire-detection and fire-fighting systems should always be provided for any turbogenerator installation. 

The latest designs for onshore installations cater for a centralized control room, well distanced from the operating facility with sub control areas as part of a distributed control system (DCS). The sub-control areas are closer to the processes but contain fewer personnel and process control systems for the overall plant, so the overall risk level for the facility from a major incident is lowered. The outlying control buildings (sometimes referred to as PIBs or SIHs) still need to be sited against impacts from explosions and fires. 

A fire risk assessment should be documented to provide a clear overall picture of the possible fire hazards and the role safety systems play in hazard control and mitigation. Also, a fire risk assessment should be maintained evergreen during the lifecycle of the facility to ensure ongoing management of fire hazards. 

Increasingly, newer fired process heater installations are adding more fuel-air combustion controls and safety instrumentation systems. However, the decision on the extent of fired heater combustion controls, instrumentation, and safety systems to employ is fundamentally a loss prevention and risk tolerance issue, rather than a fire protection one. The following recommended practices, codes and standards apply to fired heater and dryer controls and instrumentation ... 

Adheres to health system and departmental policies and procedures. Complies with all requirements related to risk management, safety, security, fire, and infection control. 

All wiring and electrical components used in any control system must be rated for the current and voltage carried. If they are not, there is a risk of overheating components and/or starting a fire on wire insulation, etc. All electrical connections whether mechanical or soldered need to be done well so that shorts do not occur between wires, terminals or soldered joints. 

Topics Include methods lor calculating damage resulting from the physical effects of accidental releases, using risk assessment Information to specify safety control systems, fault tree analysis, hazards of trace substances, warehouse fires, human exposure to process systems, and solutions to human factor problems. 

The apphcation of additive injection involves the installation of an additive silo, an injection system and, in the case of carbon injection control measures to prevent additive build-up. In order to prevent fire risks, activated carbon may be mixed with lime and may be injected, after the first filtration but before a dedicated secondary filter unit. 

The What-if method is the simplest method to assess chemical process safety risks and is based on questions such as What if the mechanical or electrical integrity of the process, the control systems and work procedures all fail,. .. what consequences could arise in the worst case While the potential consequences are largely determined by the inherent hazard of the material and the quantity involved, the reviewer is focused on safety concerns, e.g. those arising from fire, explosion, toxic gas release, and environmental protection. 

To support the safety culture within the organisation > To ensure the success of any safety programmes and support the safety management system > To ensure compliance with risk control strategies, e.g. fire wardens training to assist in the safe evacuation of a building. 

Key risk control measures, e.g. security, user checks, permit to work system > The emergency procedure for the workplace, e.g. the sound of the fire alarm, the location of the assembly point... 

The controlling valves for drencher systems are located in accessible positions on or near ground level but away from the adjacent fire risk. The valves are secured against unauthorised interference, protected from frost and clearly indicated. 

An effective auditing programme will be able to provide a comprehensive picture of exactly how effectively and efficiently the fire safety management system is controlling fire risks. The programme should also identify when and how each of the component parts of the system will be audited. Due to the technical nature of some of the workplace precautions (e.g. detection and alarm systems, sprinklers, etc.) these may be required to be audited on a more frequent basis than other elements of the system and the auditing process should reflect this. 

Engineering controls should be used to isolate or insulate heat sources from any combustible material or flammable atmospheres >- Hot work should be reduced to a minimum >- Maintain good levels of housekeeping >- Provide safe systems of work that minimise fire risk >- Provide adequate training, instruction and information relating to fire safety... 

However, where local containment is not provided, or the fire risk assessment indicates that additional control measures are required, for example to contain firewater run-off, which may amount to thousands of cubic metres, remote containment systems may be appropriate. Remote containment systems may be used by themselves, or in combination with on-site containment arrangements. They may be required to protect both surface and foul water drainage systems. 

It is often the case that a fire safety inspection will not identify issues such as the control of contractors as being a risk, unless contractors and maintenance operations are being undertaken at the time of inspection. This issue must be included in a risk assessment as it is reasonably foreseeable that contractors may either compromise the safety of those on site while undertaking their operations, or compromise fire safety compartments or other control systems. 

The prioritisation of any recommendations contained within the action plan will also need to reflect, not only the level of risk, but also the feasibility (practicality) of implementing the prescribed workplace precautions and risk control systems. Risk assessments that merely list long-term recommendations, such as review. .. policy are unlikely to address the immediate requirements for managing fire risks, waiting for a formal policy or procedure, for example a review and revision of contractor selection and management due to poor management of hot work operations, may well take some time to be produced, approved and implemented. 

Where intermediate control measures are introduced such as the provision of additional fire wardens/security teams to cover for a lack of fire warning/detection systems, the fire risk assessment should be reviewed regularly to ensure that any such intermediate control measures remain effective. 

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