Fire-safe environment

The ultimate objective of the study of toxicity of fire-produced toxic agents is the design and construction of a fire-safe environment. There are many ways to accomplish this aim. We might develop materials which, when heated, produce no toxic gases. We might use materials which do not bum. 

The rotor design, its cooling system or the motor size itself may have to be changed substantially for motors to be installed in fire hazard environments to limit their temperature rise in adverse operating conditions within safe limits (Table 7,6). 

Valves. It is desirable and inherently safer to use fire-tested valves whenever it is necessary to isolate flammable or combustible fluids in a pipeline or tank or other type of equipment. Fire-tested valves were formerly called fire-safe valves. They were not really firesafe, and the name has been changed to fire-tested valves. Fire-tested valves should be considered for handling most fluids that are highly flammable, highly toxic, or highly corrosive and that cannot be permitted to escape into the environment. 

An internal disaster occurs when there is an event within the facility that poses a threat to disrupt the environment of care. Such events are commonly related to the physical plant (e.g., loss of utilities or fire), but can arise from availability of personnel (e.g., a labor strike). Regardless of the cause, the management goal is to maintain a safe environment for the patients, continue to provide essential services, ameliorate the problem, and restore normal services. 

The most logical starting point in tlie safety design approach is to select a site where tlie number of undesirable weather and topograpliic conditions is limited. Adequate utilities and support systems plus fire protection service arc also required for a safe environment. Chapter 5 presented a detailed account of phuit site selection and layout. These features will now be considered from a safety point of view. Tire following guidelines should be observed in determining a site tliat is favorable for tire efficient cuid economical operation of the process. 

Fire is a dangerous and potential threat to the btiilt environment and it may turn into a disaster if not well controlled. In any case, fire safety must be considered at the design stage of new buildings. The principles of fire-safe design are outlined in... 

Fire safety in building design is aimed at providing a safe environment for occupants while inside the building. Provision is also made for a safe means of escape for all occupants since a fire emergency usually involves evacuation to a place of safety. Obviously the effectiveness of the means of escape that is provided in any building is reliant upon how they are used at the time of an emergency by individual occupants. 

We would like our built environment to satisfy a performance code which states that "all occupants of this building will be able to safely exit or reach a safe refuge area no matter where or when a fire starts."... 

The mission instructions are repeated once again reconnoiter the area indicated on their maps, observe and report enemy activity and search for items useful to the intelligence unit. Move cautiously, as if in a combat environment. If a sniper is visible and is firing a weapon from a hiding place in the woods, return fire and resume the mission. When encountering gas, mask immediately. Check to see that the mask is cleared and properly adjusted. When safely across the road and in the clear, remove the mask and return it correctly to its carrying case. 

To protect against the explosion and fire hazard, a plant manager should (a) have qualified plant personnel field monitor for explosive atmospheres and flammable vapors, (b) keep all potential ignition sources away from an explosive or flammable environment, (c) use nonsparking, explosion-proof equipment, and (d) follow safe practices when performing any task that might result in the agitation or release of chemicals. 

In most practical combustion installations there are two separate parts of the equipment system (1) the burner itself and (2) all of the peripheral equipment necessary to control the burner operation efficiently and safely. The control equipment includes fuel and oxidant pressure and flow controls automatic shutoff controls flame supervision equipment furnace purge equipment and other related devices. The safety issues of the burner are significantly different in character as compared with the safety issues of the control equipment. In many ways, these two safety issues are diametrically opposed. Within the burner, fire is a desired condition, whereas within the control system and surrounding environment, fire is to be avoided entirely. 

Unlike burning fossil fuels, nuclear reactions do not produce pollutants such as carbon dioxide and acidic sulfur and nitrogen compounds. However, the nuclear reactions do form highly radioactive waste that is hard to dispose of safely. Other serious problems include the potential release of radioactive materials into the environment when fires or explosions take place, and also the limited supply of fissionable fuel and the higher cost of producing electricity using nuclear fuels rather than fossil fuels. Nuclear reactors that have experienced serious accidents are shown in Figure 21.13. 

Assurances that new and existing chemical processes are conducted safely have never been more needed. Public awareness of the effects of chemical exposure has increased since the early 1970s. Although the initial focus of the Occupational Safety and Health Act of 1970 was on safety, clearly the emphasis now is on health. People at all levels of society are concerned about exposure to chemicals and the possible short- and longterm effects of chemicals on human health. The effects of chemicals on the environment from past or present waste sites, accidental releases or spills, and fires and explosions are reported daily in the news media. Control of all chemical processes to avoid accidental discharges and/or upsets that lead to fires, explosions, and environmental release is essential in the laboratory, the pilot plant, and the manufacturing plant. Chemical process hazard reviews are necessary at each step in the development of a process to ensure that the process can be controlled and conducted so as to minimize the risks to personnel, property, and the environment. 

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