Explosion management, principles

Due to the destruction nature of hydrocarbon and chemical forces when handled incorrectly, fire and explosion protection principles should be the prime feature in the risk philosophy mandated by management for a facility. Disregarding the importance of protection features or systems will eventually prove to be costly in both human and economic terms should a catastrophic incident occur without adequate safeguards. 

The principles of explosion management can be broken down into two discrete areas those of control and mitigation, each will be dealt with separately. The Dangerous Substances and Explosive Atmospheres Regulations (DSEAR) require the application of a hierarchy of control measures to manage the risk of accidental explosion. 

Designs should prevent and manage combustible and explosive mixtures in air. Particularly important are processes and operations where flammable mixtures of gases, vapors, and dusts with air can occur. This principle includes reducing oxidizers that add to the explosive energy of a combustible material. Fuel and oxidizers require separated storage. That is because of the increased risk when fuels and oxidizers are located adjacent to or near each other. 

Recent disasters in Australia in different industries have prompted different regulatory responses. In the state of Victoria, a gas plant accident which disrupted supplies to the state for two weeks (Hopkins, 2000) has led to the introduction of a safety case regime, while in the state of Queensland, a coal mine explosion which killed eleven men (Hopkins, 1999) led to a requirement that mines develop principle hazard management plans. This paper looks at the characteristics of the two different styles of regulation, explores reasons for these different responses, and draws some tentative policy conclusions. 

Examination of this list reveals that it is not simply a list of six hazards for which plans must be developed. It refers to both specific hazards (e.g. spontaneous combustion) and general control systems (e.g. ventilation management), which may be applicable to more than one hazard. The principle hazards are to some extent implicit in this list. They include methane gas explosions (which may or may not trigger coal dust explosions), carbon monoxide poisoning, roof or wall collapse, and the long latency period dust disease, pneumoconiosis, which has probably killed more miners in the long run than anything else. 

Fixed heaters are extensively used in the oil and gas industry to process raw materials into unstable product in a variety of processes. Fuel gas is normally used to fire the units that heat process fluids. Control of the burner system is critical in order to avoid firebox explosions and uncontrolled heater fires due to malfunctions and deterioration of the heat transfer tubes. Microprocessor computers are used to manage and control the burner systems. Principle functions of the burner management system are provided with programmed ignition of niters and burners at lightoff, flame monitoring during boiler operation, and proper furnace shutdown. 

The contractor updates the REPA to include the results of concept optimisation. Norskoil s project SHE manager supervises this work. It is shown that the concept meets all appUcable acceptance criteria, provided that a number of assumptions are met. These define the accidental loads from fire, explosion, dropped objects and ship collisions that the semi mnst be able to withstand. Another set of assumptions defines the safety and communication systems that have to be operable during an accident. There are also assumptions regarding the collision warning system and the withdrawal of the platform from the snbsea wells in case of blow-out. The REPA also results in a number of recommendations based on the ALARP principle. The assumptions and recommendations serve as input to design development and to specifications and need to be followed up in later project phases. 

---