Fire monitor

Monitors are fixed water hydrants with an attached discharge gun. They are also installed in process areas and storage tank areas. Fire hydrants and monitors are spaced 150 -250 ft apart around process units, located so that all areas of the plant can be covered by 2 streams. The monitor is usually located 50 ft from the equipment being protected.14 Fire monitors discharge water at a rate of 500-2000 gpm. 

Processes susceptible to a runaway reaction during fire exposure shall be protected by water spray systems and fire monitors. 

Materials or containers stacked or placed so that they block the effective discharge of sprinkler or deluge fire protection systems or fire monitor nozzles. 

Access to manual fire monitors and personnel availability. 

Fire monitors should be provided and positioned so that at least two monitor streams can reach each process area, preferably from opposite sides. Often, fire monitors are mounted directly on hydrants. Care should be taken to select and position fire monitors to ensure that their streams can reach elevated equipment. The local fire main s residual pressure under flowing conditions should be determined to ensure it is adequate to deliver effective water streams capable of reaching all elevated equipment. While monitors need to be close enough such that their stream reaches elevated equipment, if they are too close it may not be possible to physically access the monitor to direct its stream due to radiant heat. In these cases, some form of personnel shielding or remote operation is required. 

Use of manual fire monitors or area coverage water spray or deluge systems are typically sufficient for the fire protection of heat exchangers. However, where exchanger support saddles exceed 12 in (30 cm) in height, the supports should be protected by either water spray at a density of 0.3 gpm/ft (12 Ipm/m ) or application of fire resistive material. 

Despite the limitations, there are sufficient advantages in the use of portable foam monitors to justify consideration for tank fire extinguishment. Some foam trucks are equipped with a 1,000 gpm (3,800 Ipm) foam monitor or snorkel articulated boom with a 500 gpm (1,900 Ipm) monitor. In addition, a 1,000 gpm (3,800 Ipm) portable monitor is recommended and can be towed behind the foam truck for use on tank or spill fires. Monitors have the advantage of fire extinguishment without close approach, resulting in less personnel hazard than the use of foam hose lines. 

Outdoor storage areas are seldom provided active fire protection by fixed systems to protect them from exposure by events in adjacent areas. However, on a case-by-case basis, specific fixed fire protection systems, often fire monitors, may be added where the outdoor stored material ... 

If trained to do so and confident that you are capable, activate any fire monitors and/or fixed fire water systems in the immediate area and attempt to cool the tank and surrounding equipment. If the tank is receiving material or product, close a valve on the inlet line at a safe location. Stand by to direct the Emergency Response Team (ERT) to scene Use appropriate Personal Protective Equipment (PPE) First Responder... 

After 11 30 a.m. Automatic deluge sprinkler system found to be severely damaged by fire/explosions and is now valved into OFF position. Three fixed fire monitors directed on fire at full flow. Two hose streams from hydrants directed on fire also. 

At 4 30 A.M. on July 21, 1988, a plant protection officer making rounds saw and heard vapors emitting from the relief valve on tank car UTLX 647014. This report indicated that the contents of the car, technical methacrylic acid (TMAA) were reacting, and that we had a serious situation. The car was in a marshalling yard awaiting transfer to a terminal. Cars filled with hazardous materials, which were near the reacting car, were removed, and empty cars were moved into position on its south side and west end. Remote fire monitors were placed into position on the north side and directed at the relief valve and the dome in an effort to control vapor emissions during the remainder of the reaction. The east end of the car could not be reached. Fortunately, the car at that end was empty. Personnel were kept away from the car as much as possible from the time vapor emissions were noticed. At about 12 25 A.M. on July 22 (about 20 hours after the problem became known), the car ruptured. 

Rouse, Hunter, Howe, J. W., and Metzler, D. E., Experimental Investigations of Fire Monitors and Nozzles, Trans. ASCE 117 1147-1188, 1952. 

Schatz and Koopman (1990) reported on the Hawk series, 87 tests conducted at the DOE Nevada test site. These experiments were large-scale chamber releases of HF, as well as laboratory experiments. The objective of these tests was to study the effect of the water-to-HF ratio, water spray geometry, water application via a fire monitor, acid type (anhydrous HF and alkylation unit acid (AUA)), acid temperature and pressure, water additives, relative humidity, wind speed, and steam as an acid jet dispersant on HF removal efficiency. Figure 4.2 shows removal efficiencies ranging from 25 to 90% for water-to-HF volumetric flow ratios ranging from 6 1 to 40 1. Fire monitors provided removal efficiencies comparable to those of water sprays. Some of the conclusions reached by the authors were ... 

Petersen, R. L., and D. N. Blewitt. 1992. Evaluation of Water Sprays/Fire Monitor Mitigation for Two Refineries. New York American Institute of Chemical Engineers. 

The emergency response teams first concern was cooling the tank to reduce the possibility of rupture. Cooling water from fire monitors was sprayed on the shell of the vertical, cylindrical vessel and was sufficient to prevent a rupture. Later the acids were slowly mixed and scheduled to be neutralized with caustic. 

Responsibilities for performing specific actions during the emergency Appropriate personal protective equipment (PPE) or other protective devices (showers, eye wash stations, first aid supplies, extinguishers, fire monitors, deluge cannons, emergency carts)... 

Dispersants must always be applied with a system designed specifically for the purpose. If pesticide spray equipment is used, small droplets form that may blow away and not enough dispersant is deposited onto the oil slick. Unless suitably modified, fire monitors or regular hoses from ships may not result in correct droplet sizes or quantities of dispersant per unit area. Furthermore, the high velocity of the water/dispersant mixture can herd the oil away, resulting in the loss of dispersant to the water column, where it has little effect on oil floating on top of the water. 

Maps are also handy for operations involving vehicle movement. If, e.g., a truck of hazardous chemicals arrives at the gate of the facility, the security guard can provide the driver with a map of the roads to the location where he is to unload. Maps can also show the layout of safety equipment such as fire monitors and extinguishers. 

Fire monitors and turret nozzles (grade and elevated)... 

Explain how fire monitors are used to fight fires. 

Go to www.YouTube.com and find a video about fire monitors, foam used in fire fighting, or the toxicity of smoke. Write a one page report about wbat you discovered. 

Fire sprinklers, fire monitors and deluge system design details... 

If you have welders and welders helpers (fire monitors, etc.) extended classroom and hands-on training is required to meet OSHA requirements. This toolbox talk is intended as an overview of welding safety rules. 

EXHIBIT 13-31 Typical Grade-Mounted Fire Monitor... 

Fire monitors are used to direa streams of water to burning pieces of equipment in a plant. Before monitors are selected and located, several faaors must be considered. Fire monitors are lever operated, have a full 360° range, and may be locked in any desired position. They may be located at grade, approximately 4 ft (1,200 mm) above the ground, elevated to heights of 100 ft (30 m) or more, or mounted on a hydrant. The spray pattern of fire monitors depends on water pressure and flow rate. If vendor data is not available when preliminary fire water layouts are made, the chart in Exhibit 13-30 can be used to determine the effective fire water monitor range. This chart is based on a water pressure of 150 psi and a flow rate at the nozzle of 500 gpm. 

Study effectiveness of water sprays and fire monitors in mitigating HF releases with varying wind speeds and directions in two different refinery unit configurations. 

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