FIRE PREVENTION AND LOSS CONTROL

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF resistance to fire effects, and which are required to contain flammable liquids and gases and/or to control the disruption resulting from afire, will be "Fireproofed High Integrity Seals
This Section to be developed Ignition Sources
Ignition sources will be restricted to safe distances from potential fuel sources so as to reduce the probability of ignition of released flammable materials.
All areas where flammable gases or vapors are, or maybe, present in the air in quantities sufficient to produce ignitable mixtures are electrically classified as hazardous areas per the National Electrical Code, IEEE, and local code requirements. A plot plan of the facilities will be developed that indicates the degree and extent of the electrical area classifications for each area. Where it is not practical to locate ignition sources outside of classified areas, only explosion-proof electrical equipment, purged electrical enclosures, or intrinsically safe equipment will be used to prevent ignition).

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF 50 Loss Control Passive Fire Protection
Grading and Drainage Consideration will be given in the design of sewer systems and grading to preventing the ignition of fires should a release occur and to controlling fire effects by limiting its spread. Liquid fuel sources will slope away from potential ignition sources and a sump and/or a sealed sewer system will be used to prevent flammable vapors from reaching ignition sources. Where sumps and pumps are used in the drainage system to remove spilled materials from process areas, the pumps shall be provided with an emergency power supply to ensure they will be operable under power failure conditions. Catch basins will not be located directly beneath equipment in order to limit flame impingement on vessels or air fin coolers and to minimize fire spread among adjoining equipment items. The high point of paving will be the centerline of main pipe racks in process areas to drain spilled liquids out from under the pipe racks and minimize fire exposure to such equipment
Equipment Spacing See Reference 27 General Recommendations for Spacing. Also
NFPA 30 provides minimum standards for spacing.
Containment Containment maybe achieved by the use of curbing or dikes or by grading to drain spillage at an adequate rate to remote containment (a sump or pond. Containment around storage tanks should be designed to hold a minimum of 110% of the capacity of the largest tank within the berm (or in remote containment) in order to contain spills to protect the environment. The use of remote containment is preferred since it reduces the risk of having to contain multiple tank spills (while burning, plus firewater. Grading around an individual tank should carry spills away from the tank. Several tanks maybe located within the same berm as long as their contents are not incompatible where this is done, intermediate dikes are recommended along with grading to minimize the effect on the adjacent tanks.
In the event of unzip (failure of the vertical seams of the tank shell) of a tank or boil over, released materials may surge over the berm. Fireproofing Structural support materials will have a minimum fire resistance rating of three hours (per hydrocarbon high-rise time temperature

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF curve) and critical electrical circuits, instrument circuits and motor operated valves (and related power/activation systems will be protected fora minimum of 20 minutes to allow for safe unit shutdown. Fireproofing provided in areas subject to mechanical or physical damage shall be concrete type fireproofing. Where process vessels are located in fire hazardous areas of the facility and heat conservation insulation is required, these systems must be upgraded to fire rated type systems to provide the required fireproofing rating. (Reference 4; API-2218)
Where fireproofing of electrical and instrument control cables is required, inherently fire resistive cable systems shall be used. Motor operated valves and other enclosures shall utilize shop applied intumescent fireproofing. Where intumescent fireproofing is utilized, local environmental factors and proximity to local heat producing equipment shall betaken into consideration to ensure that the coating does not prematurely intumesce resulting in a reduction of the fireproof rating provided.
Fire Walls Where two or more transformers (containing 500 gpm or more of oil) are located together, a hour rated firewall in accordance with
NFPA Reference 21) shall be provided between each transformer. In accordance with NFPA 850, a hour rated firewall is also required between the transformer and buildings less than 25 ft from the transformer. The transformer pad will also be sloped away from the equipment with drainage to the appropriate sewer or a curbed area to retain spilled transformer oils. Fire Walls are used to separate areas, which require sprinkler systems (such as a labor kitchen) from areas where water spray is to be avoided (such as control or computer room Automatic Fire Protection
Large, complicated automatic fire protection systems often have a dedicated Fire and Gas Control Panel. Such a system monitors the Fire Water System (pressure, pump status, control valve status, water tank level, etc. Additionally, the Fire and Gas Control System would monitor any heat, smoke, gas detection systems, water flow to any sprinkler spray or deluge systems, and release of any fire suppression systems (CO, clean agent, or powder. The system would sound the audible alarm, identify the problem location, and call the fire department. From this system, shutdown and isolation systems and water and foam spray or deluge systems could be manually actuated.

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF Fire Detectors look for heat or combustion products. Heat detectors include fusible links (the simplest type, bimetallic fixed-temperature systems, rate of rise detectors, and rate- compensated heat detectors. Combustion product detectors include the various types of smoke detectors, and IR or UV flame detectors.
Flammable Gas Detectors detect process system leaks. Their purpose is to prevent fire. When designed to be highly reliable, they maybe used to shutdown and isolate equipment, or start water spray systems.
Alarms (Section to be developed)
Automatic Response (Manual vs. Automatic Activation) Facilities where significant amounts of liquid flammable chemicals are stored and which are not manned around the clock by personnel trained as first responders and occupied buildings except where there are significant electronic systems which could be damaged by water) are the most appropriate locations for firefighting systems which are activated and alarmed automatically.
Detection systems for automatic fire suppression systems must be selected and installed to have a high degree of reliability (work when it should – not when it shouldn’t). Otherwise, unnecessary activation of these systems can lead to water damage, or, worse, waste the firewater supply where it is not needed.
Automatically activated systems will be capable of manual activation locally from a safe location or remotely. Automatic Response (Shutdown, Isolation) Due to the consequences of nuisance trips, automatic shutdown and isolation systems should be designed to be very reliable and with a full consideration for followup response Fire Water System
Firewater is used in almost all major firefighting applications. Therefore, Fire Water Systems are required for almost all chemical process facilities. Firewater is used to extinguish fires, to cool surfaces so that they do not catch fire, or reignite fires, or begin to loose strength due to heat, to cool firefighting personnel as they approach fires, to wash away spilled materials.

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF Firewater is also used to mix with foams, which are used to cover the surfaces of flammable liquids. This reduces the production of vapors which feed the fire and separate oxygen from the fuel.
On the other hand, improper application of firewater can waste this potentially limited resource, spread flammable and flaming liquids to wider areas, or sink or cock floating roofs, increasing the liquid surface area which can become fire involved.
4.2.3.1
Supply and Storage
In most cases, firewater systems are wetted, i.e., the firewater distribution system is full of water and is maintained under pressure ready to deliver water instantly. Also, firewater delivery equipment normally incorporates spray nozzles, which can become plugged and ineffective if the water is not clean. Therefore, the water must be clean.
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Water maybe pumped from rivers or lakes. Suction must be below the lowest water level. Suction screens / skimmers and spares will be required and must be inspected and cleaned regularly to assure they aren’t too fouled for maximum flow rates. Filtration must be provided which is adequate to prevent plugging of the spray nozzles.
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Water treatment is required to prevent the growth of organisms in the system.
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Seawater maybe used. In addition to the suction straining and filtering and treatment to prevent the growth of organisms, saltwater would affect the metallurgical choice for the firewater system materials of construction and require additional inspection requirements for any process vessels or structural steel sprayed during firefighting efforts. Potable or non-potable water maybe obtained from municipal or industrial community water supplies or from onsite wells. It is usually desirable to have more than one water source for reliability.
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Unless the water supply is capable of a delivery rate and pressure sufficient for firefighting and has a high degree of reliability, a Fire Water Storage Tank will normally be required. Filtered, treated water will be made up into it as needed to keep it full.

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF The minimum usable storage capacity of the Fire Water Tank is for four hours of water deliver at 100 to 120% of the governing case. This would be increased if the replenishment rate is relatively slow or if the makeup water supply is less than completely reliable. (Sometimes alternate water supplies such as Utility Water storage tanks, Cooling Water storage tanks, Storm Water holding ponds, etc. are made available).
4.2.3.2
Fire Water Pumping
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Jockey Pumps are used to maintain a constant pressure on wetted firewater distribution systems. There is usually one
100% pump and a spare. Each pump is rated sufficiently to cover a small amount of system leakage plus some allowance for wash down at fire monitors or system flushing. 100 – 150 gpm is common with a discharge pressure of approximately
125 to 140 psig. The primary Jockey pump runs continuously circulating around the Fire Water Tank on discharge pressure control. The spare pump starts automatically if the primary Jockey pump fails.
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Fire Water Pumps are used to deliver large quantities of water to the firewater distribution piping. One or more of these pumps are provided with a combined design flow capacity of at least the required delivery rate (120% of the largest calculated governing case) and with a discharge pressure sufficient to deliver the required flows to any firefighting equipment around the firewater ring main (at a minimum of 100 psig) and subject to system hydraulics with any single section of the ring main isolated and out of service.
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Consideration will be given to assuring the reliability of the Fire Water Pumps (separate power supplies, emergency generator, diesel driven, etc) At least one spare Fire Water Pump is provided sized to match one of the primary Fire Water Pumps (i.e. there will be two 100% pumps or three 50% pumps or four 33% pumps etc.).
These pumps, including the spare, start automatically and sequentially at a set pressure a little below the Jockey Pump operating and startup pressures. See Appendix 4 for an example of a Fire Water pumping system.
4.2.3.3
Fire Water Ring Main
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The Fire Water Ring Main should be buried. It will require sufficient isolation valves such that, if one section is removed from service, no fire hazardous equipment will be completely

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF deprived of firewater supply. The ring main is usually laid out around the edges of the chemical plant and along roadsides branches are used to deliver water to firefighting equipment located within unit boundaries.
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Almost any kind of pressure-rated pipe can be used to carry the firewater.
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HDPE pipe has many advantages (corrosion resistance, flexibility, resistant to surge pressure, smooth surfaces which do not lose flow capacity overtime, however care should be exercised in sizing since the pipe size is based on OD. and the walls are thick. Also the pressure rating is based on a design temperature of 73 F and is reduced significantly as the temperature rises. (See Appendix Metallic lines are subject to corrosion internally as well as externally and their flow capacities will gradually deteriorate as the pipe ages. Where used, an external coating is usually required.
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Concrete lines are more susceptible to fracture and seal failure and they gradually lose their flow capacity with the growth of organisms, which adhere to the walls.
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Post Indicator Valves (UL or FM approved) are used to sectionalize the ring main such that if one section has to be isolated and removed from service, no area will be left completely unsupplied with firewater. Generally, no more than one hydrant will be connected to a single section no more than four fire monitors will be connected to a single section. Especially critical firefighting equipment will have connections to two sections of ring main. (See Appendix 3 fora typical Ring Main Layout Fire Fighting Equipment
See Appendix 5 for references to many of these types of equipment.
4.2.4.1
Fixed Fire Monitors
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Fire monitors are considered to be the primary firefighting tool. A single person may quickly start fire monitor flow, aim the stream, adjust the stream, lock the monitor in place and then proceed to use additional monitors, foam hose reels, or fire extinguishers, to communicate, or to temporarily evacuate the area.

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF For the purposes of layout of monitors, monitors shall have a maximum effective stream range of 120 feet with a maximum vertical height of 148 feet at a degree elevation. Fire Monitors are manufactured in for various flow rates (typically
250-500 gpm, and water supply conditions (typically 100 psig). They are also available with siphon connections for small foam containers. Longer-range monitors are available.
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Monitors are located to protect equipment normally there would beat least two monitors with coverage areas for any fire hazardous equipment or equipment in afire hazard envelope. Monitors maybe located within afire hazard envelopes, however, the monitors assigned to any particular equipment should be no closer than 40 feet from that equipment one of the two monitors should be within 85 feet of the equipment and the other should be within 120 feet of the equipment. The two monitors should be located (to the extent possible) such that if one is inaccessible (due to wind, smoke, fumes, etc) the other will be accessible. Ideally, the two monitors would be supplied separately such that if one section of ring main were out of service, at least one of the monitors would still be supplied. This may not always be feasible and some other backup plan would be in place. Monitors are available, which can be operated remotely (for locations inside a storage tank dike, for example) or which can be started manually and left oscillating (this feature could be particularly useful for cooling storage tank walls with more concentrated streams and at greater distances).
4.2.4.2
Water Spray Systems/Deluge Systems Sprinklers Fixed Foam Spray Systems
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These systems are used for the protection of equipment, structure, buildings, stored materials, etc. Whether actuated automatically or not there should always be provision for manual startup and shutoff from safe location.
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These systems are sometimes used when afire monitor is inappropriate (i.e. there is too much interference with the flow path or the monitor cannot be located close enough).
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A fixed foam spray system would include an appropriate amount of foam in a container ready to be educted with manual or automatic start of water flow.
Wherever sprinkler or spray nozzles are used, the system must include strainers in the water supply.

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF 50 Fire Water And Foam Hose Reels
These systems are usually rated for about 60 gpm and are used by an individual in a precise way to extinguish incipient fires similar to afire extinguisher (in fact, given that the hoses are about 60 feet long, they are somewhat portable. These are located for use at pumps where flammable materials may leak and ignite.
4.2.4.4
Fire Hydrants
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Fire hydrants are for use with mobile equipment. Typically wet barrel hydrants are provided with three small (2-2.5”) valved connections and one large (4-5”) valve connection. Hoses are used to connect the water supply from the hydrant to the mobile equipment or (when manned by several firefighters) maybe used to fight the fire directly.
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Hydrants are usually located along roadsides (close to the ring main) spaced no greater than about 150 ft (the length of one fire hose) apart.
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The 4-5” hose connections can handle on the order of 1000 gpm.
4.2.4.5
Semi-Fixed Systems
Semi-fixed systems are those where a distribution system for the fire suppressant (foam for example) is available upon arrival of mobile supplies. Firefighting foams can be expensive, so it maybe decided to install a limited amount or none, with the expectation that a portable supply would arrive quickly, be connected, and the system activated manually.
4.2.4.6
Portable Equipment
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Portable fire extinguishers should be located throughout all areas and within all buildings. The extinguisher agent selected in each case will be based upon the class of fire to be expected as follows:
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Class A (Wood, paper and similar) - water
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Class BC (Hydrocarbon and/or energized electrical equipment) - dry chemical or carbon dioxide gas
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Class ABC (All the above) - multipurpose dry chemical or carbon dioxide gas Wheeled portable dry chemical and wheeled premixed foam fire extinguishers maybe provided for each process area and other high hazard equipment

FIRE PROTECTION PHILOSOPHY AND DESIGN GUIDE
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Nov. 11, PAGE OF Foam Containers (small one to five gallon containers which can be hand carried or carted to afire monitors equipped for foam eduction).
4.2.4.7
Mobile Equipment
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Most mobile firefighting equipment is designed for use by or for dedicated firefighters. It is kept in a Fire House and used under the instructions of a Fire Chief or Incident Commander. It may not be available fora short period after afire alarm is sounded due to necessity for the fire department members to gather, don emergency PPE, and travel to the site of the fire.
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Not every facility will have a full compliment (or any) of this type of equipment and may rely on a municipal fire department or industrial community aid program. Some types of Mobile Emergency Equipment to consider:
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Monitor – A mobile fire monitor usually equipped with enough hose to connect to afire hydrant supply.
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Aerials – This apparatus can extend a remote controlled firewater nozzle 60 to 100 feet at angles of –5 to 75 to fight elevated fires or where afire cannot be safely approached. The truck generally includes a booster pump to supply the nozzle, a water tank for pump suction, and enough hose to connect to afire hydrant supply. (These trucks may include a platform for manual operation of the nozzle.)
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Hose Truck. This apparatus carries many types of firefighting equipment, primarily hose for connection to hydrants. The truck may tow trailerized fire monitors, foam guns, foam tanks, etc.
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Support Trucks – This apparatus may include an air conditioned space for cool-down of firefighters (in hot climates, drinking water, storage for SCBA and spare bottles, escape packs, bunker gear, first aid supplies, and PPE, aside mounted bank of lights for use at night, etc. They may tow a breathing air bottle rack, etc.
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In many cases, several of these capabilities are combined into a single vehicle.
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Additionally, a Fast Attack Truck maybe provided for use by trained operations personnel. This vehicle is essentially a large pickup truck with communications gear, PPE, SCBA, a small drum or two of foam for use with a fixed fire monitor, fire extinguishers, possibly a small foam gun with a 50 gallon supply of foam and some hose for connection at hydrants or fixed monitors, eyewash bottles.

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Nov. 11, PAGE OF 50 4.2.5 Other Fire Suppressants
The following are typically used when solids or very small liquid spills are on fire, burning insulation and building materials, grease, lubricants, etc.
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FM-200 (heptafluoropropane) (Kidde) is reported to be a replacement for Halon. No Ozone Layer depleting CFC’s, safe at firefighting concentrations. The fire is extinguished without getting sensitive electrical and control equipment wet or covered with dry powders.
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High Pressure Water Mist Systems (Marioff) produce a fog, which acts by inerting the atmosphere, by cooling, and by blocking radiant heat. These systems have been used instead of halon replacements or CO. Water use (and thus water damage) is minimal (in some cases 2% of conventional sprinkler system usage).
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Snuffing Steam is used as an aimed spray at flanges inside isolation limits of equipment containing easily ignited materials under high pressure. Dry Powder – Dry powder is sprayed from a portable extinguisher
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Wet Chemical – Liquid fire suppressant is activated automatically or manually to spray directly on afire primarily used on kitchen equipment.
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CO2- CO gas is sprayed from a portable extinguisher or fixed spray system to smother afire. CO is not used in confined space when people are present.

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