Most know NFPA 30 and OSHA’s 1910.106 for managing flammable liquid hazards. I have often written about the International Fire Code and its value to those looking for additional measures to reduce risk. In this situation, it does not disappoint when it comes to “Bulk transfer and process transfer operations.”…
|
5706.5 Bulk transfer and process transfer operations Bulk transfer and process transfer operations shall be approved and be in accordance with Sections 5706.5.1 through 5706.5.4.5. Motor fuel-dispensing facilities shall comply with Chapter 23. |
This section gives the fire code official the authority to require approval of bulk transfer and process transfer operations.
|
5706.5.1 General The provisions of Sections 5706.5.1.1 through 5706.5.1.18 shall apply to bulk transfer and process transfer operations; Sections 5706.5.2 and 5706.5.2.1 shall apply to bulk transfer operations; Sections 5706.5.3 through 5706.5.3.3 shall apply to process transfer operations and Sections 5706.5.4 through 5706.5.4.5 shall apply to dispensing from tank vehicles and tank cars. |
These sections cover facilities used for bulk transferring, bulk processing, and bulk dispensing to tank vehicles and tank cars.
|
5706.5.1.1 Location Bulk transfer and process transfer operations shall be conducted in approved locations. Tank cars shall be unloaded only on private sidings or railroad-siding facilities equipped for transferring flammable or combustible liquids. Tank vehicles and tank cars engaged in bulk transfer or process transfer operations shall be separated from buildings, above-ground tanks, combustible materials, lot lines, public streets, public alleys or public ways by a distance of 25 feet (7620 mm) for Class I liquids and 15 feet (4572 mm) for Class II and IIIA liquids measured from the nearest loading or unloading valve on the tank vehicle or tank car. Exception: Buildings for pumps and shelters for personnel supporting transfer operations shall not be required to be separated from tank vehicles and tank cars engaged in bulk transfer or process transfer operations. |
The volume of flammable and combustible liquids being transferred and processed requires that the location be protected from ignition sources.
This is accomplished by maintaining minimum clearance between the transfer and process operations and buildings, lot lines, public streets, alleys, public ways, and above-ground tanks.
Note that the requirement only applies to Class II and IIIA liquids, which is consistent with Section 2305.1.1 addressing delivery vehicle locations at motor fuel-dispensing facilities.
The language also clarifies that any measurements are to the nearest loading or unloading valve on the tank vehicle or tank car.
The exception recognizes that a shelter or building used for weather protection or in support of transfer operations is not intended to be separated from such activities.
|
5706.5.1.2 Weather protection canopies Where weather protection canopies are provided, they shall be constructed in accordance with Section 5004.13. Weather protection canopies shall not be located within 15 feet (4572 mm) of a building or combustible material or within 25 feet (7620 mm) of building openings, lot lines, public streets, public alleys or public ways. |
This section clarifies that an open structure with only a noncombustible roof is considered outdoor storage.
A structure with no walls and only a noncombustible roof provides sufficient ventilation to treat the storage area as outdoor storage.
Separation from buildings and openings is needed to prevent the vapors from flammable and combustible liquids from being exposed to an ignition source.
These separation requirements also limit potential property and life losses.
|
5706.5.1.3 Ventilation Ventilation shall be provided to prevent accumulation of vapors in accordance with Section 5705.3.7.5.1. |
The requirements of this section for a mechanical ventilation system are identical to those in Section 5004.3.
The mechanical ventilation system must remove vapors to prevent accumulation in concentrations in the flammable range for the flammable and combustible liquids being used.
Natural ventilation complying with Section 5004.3, which can be demonstrated to be effective for the flammable and combustible liquids being used, is an acceptable alternative.
|
5706.5.1.4 Sources of ignition Sources of ignition shall be controlled or eliminated in accordance with Section 5003.7. |
Smoking and open flames are strictly limited around flammable and combustible liquids.
Section 5003.7 prohibits smoking or open flames within 25 feet (7620 mm) of outdoor storage of flammable and combustible liquids and anywhere indoors where there are flammable and combustible liquids or where vapors from flammable and combustible liquids may occur.
|
5706.5.1.5 Spill control and secondary containment Areas where transfer operations are located shall be provided with spill control and secondary containment in accordance with Section 5703.4. The spill control and secondary containment system shall have a design capacity capable of containing the capacity of the largest tank compartment located in the area where transfer operations are conducted. Containment of the rainfall volume specified in Section 5004.2.2.6 is not required. |
Where flammable or combustible liquids are present, spills must be controlled to prevent the spread of liquid and vapors.
Section 5004.2 discusses using liquid-tight floors, curbs, dikes, and drainage systems to divert the liquid to a location where it can be contained and safely handled.
Section 5004.3 discusses mechanical and natural exhaust systems for indoor facilities.
The exhaust system must remove the vapors to prevent them from accumulating in concentrations in the flammable range.
The diked area must have sufficient capacity to contain the largest spillage of flammable and combustible liquids that can be released from the largest tank.
This would be the volume of the largest tank that extends above the top of the dike.
|
5706.5.1.6 Fire protection Fire protection shall be in accordance with Section 5703.2. |
The requirements of Chapter 9 apply to flammable and combustible liquids.
Fire protection is a principal means of preventing and controlling the spread of a fire.
|
5706.5.1.7 Static protection Static protection shall be provided to prevent the accumulation of static charges during transfer operations. Bonding facilities shall be provided during the transfer through open domes where Class I liquids are transferred, or where Class II and III liquids are transferred into tank vehicles or tank cars that could contain vapors from previous cargoes of Class I liquids. Protection shall consist of a metallic bond wire permanently electrically connected to the fill stem. The fill pipe assembly shall form a continuous electrically conductive path downstream from the point of bonding. The free end of such bond wire shall be provided with a clamp or equivalent device for convenient attachment to a metallic part in electrical contact with the cargo tank of the tank vehicle or tank car. For tank vehicles, protection shall consist of a flexible bond wire of adequate strength for the intended service and the electrical resistance shall not exceed 1 megohm. For tank cars, bonding shall be provided where the resistance of a tank car to ground through the rails is 25 ohms or greater. Such bonding connection shall be fastened to the vehicle, car or tank before dome covers are raised and shall remain in place until filling is complete and all dome covers have been closed and secured.
Filling through open domes into the tanks of tank vehicles or tank cars that contain vapor-air mixtures within the flammable range, or where the liquid being filled can form such a mixture, shall be by means of a downspout that extends to near the bottom of the tank. |
Static electricity will spark between surfaces with different electrical potential.
Vehicles that are or may have been used to carry Class I liquids are to be bonded.
Vehicles with open domes are to be bonded before the dome is opened.
Bonding to control static electricity can be done using wires, ground cables, metal piping or other similar means that will carry current.
Open dome tanks must use a downspout that extends to near the bottom of the tank.
This downspout will reduce the mixing of the flammable or combustible liquid with air.
Bonding to control static electricity is not necessary where static electricity is not an issue or a static spark would not act as an ignition source.
Three exceptions are given to this section:
- Combustible liquids whose viscosity prevents the accumulation of static electricity.
- Facilities and vehicles that do not handle Class I liquids.
- Vehicles that use a closed system for loading and unloading flammable and combustible liquids.
These closed systems prevent the vapors of flammable and combustible liquids from mixing with air to form a vapor-air mixture that can reach the LFL.
|
5706.5.1.8 Stray current protection Tank car loading facilities where Class I, II, or IIIA liquids are transferred through open domes shall be protected against stray currents by permanently bonding the pipe to not less than one rail and to the transfer apparatus. Multiple pipes entering the transfer areas shall be permanently electrically bonded together. In areas where excessive stray currents are known to exist, all pipes entering the transfer area shall be provided with insulating sections to isolate electrically the transfer apparatus from the pipelines. |
Bonding of piping to the transfer apparatus and to a rail prevents any stray current from arcing.
Any electrical equipment can develop stray current.
Grounding of electrical equipment, dispensing piping, and vehicles will prevent the accumulation of electrical potential, which will prevent the stray current from arcing and forming an ignition source.
|
5706.5.1.9 Top loading When top loading a tank vehicle with Class I and II liquids without vapor control, valves used for the final control of flow shall be of the self-closing type and shall be manually held open except where automatic means are provided for shutting off the flow when the tank is full. Where used, automatic shutoff systems shall be provided with a manual shutoff valve located at a safe distance from the loading nozzle to stop the flow if the automatic system fails. When top loading a tank vehicle with vapor control, flow control shall be in accordance with Section 5706.5.1.10. Selfclosing valves shall not be tied or locked in the open position. |
A top-loading tank vehicle for use with Class I and II flammable and combustible liquids must have either a self-closing valve, a control valve that is manually held open, or an automatic shutoff control valve to prevent overfilling and spillage.
The automatic shutoff control valve is to have a manual backup control valve located a safe distance from the loading nozzle.
If the dispensing system includes vapor control, the top loading is to comply with Section 5706.5.1.10.
|
5706.5.1.10 Bottom loading When bottom loading a tank vehicle or tank car with or without vapor control, a positive means shall be provided for loading a predetermined quantity of liquid, together with an automatic secondary shutoff control to prevent overfill. The connecting components between the transfer equipment and the tank vehicle or tank car required to operate the secondary control shall be functionally compatible. |
Spillage is prevented when filling a bottom-loading tank vehicle by using a loading system that loads a predetermined quantity of flammable or combustible liquid.
An automatic secondary shutoff control valve is required for a bottom-loading tank vehicle.
|
5706.5.1.10.1 Dry disconnect coupling When bottom loading a tank vehicle, the coupling between the liquid loading hose or pipe and the truck piping shall be a dry disconnect coupling. |
To prevent spillage when disconnecting the dispensing system from the bottom-loading vehicle, the system is to use a dry connection.
|
5706.5.1.10.2 Venting When bottom loading a tank vehicle or tank car that is equipped for vapor control and vapor control is not used, the tank shall be vented to the atmosphere to prevent pressurization of the tank. Such venting shall be at a height equal to or greater than the top of the cargo tank. |
Pressure is relieved in a bottom-loading tank during the loading process by venting the tank to the atmosphere.
The tank vent is to be above the top of the upper limit to which flammable and combustible liquid can be loaded.
This prevents the vent from spilling flammable or combustible liquid.
|
5706.5.1.10.3 Vapor-tight connection Connections to the plant vapor control system shall be designed to prevent the escape of vapor to the atmosphere when not connected to a tank vehicle or tank car. |
Vapor recovery systems must be designed so that when they are not in use, vapors cannot escape the connection to the tank vehicle.
|
5706.5.1.10.4 Vapor-processing equipment Vapor-processing equipment shall be separated from above-ground tanks, warehouses, other plant buildings, transfer facilities or nearest lot line of adjoining property that can be built on by a distance of not less than 25 feet (7620 mm). Vapor-processing equipment shall be protected from physical damage by remote location, guard rails, curbs or fencing. |
Vapor recovery is the most dangerous component of flammable or combustible liquid transfer.
To protect property and life, the vapor recovery equipment is to be separated from other buildings, equipment and lot lines.
The vapor recovery equipment must be protected from physical damage either by separation or by physical barriers.
Any damage to the vapor recovery equipment could create a vapor-air mixture that is flammable.
The same damage could generate an ignition source.
|
5706.5.1.11 Switch loading Tank vehicles or tank cars that have previously contained Class I liquids shall not be loaded with Class II or III liquids until such vehicles and all piping, pumps, hoses and meters connected thereto have been completely drained and flushed. |
Class I liquids and their vapors must be cleaned from a tank vehicle before loading them with Class II or III combustible liquids.
The vapors from Class I liquids can affect the response to Class II or III liquids by being the source of ignition and the initial fuel source to start a Class II or III liquid fire.
|
5706.5.1.12 Loading racks Where provided, loading racks, stairways, or platforms shall be constructed of noncombustible materials. Buildings for pumps or for shelter of loading personnel are allowed to be part of the loading rack. Wiring and electrical equipment located within 25 feet (7620 mm) of any portion of the loading rack shall be in accordance with Section 5703.1.1. |
Loading racks and buildings that are part of the loading rack and used to shelter pumps and loading personnel are to be noncombustible.
This reduces the fuel sources in the vicinity of the flammable and combustible liquids.
Electrical equipment within 25 feet (7620 mm) of the loading racks is to be classified as a hazardous location.
This removes an ignition source from the immediate vicinity.
|
5706.5.1.13 Transfer apparatus Bulk and process transfer apparatus shall be of an approved type. |
This section gives the fire code official the authority to approve any transfer apparatus.
|
5706.5.1.14 Inside buildings Tank vehicles and tank cars shall not be located inside a building while transferring Class I, II, or IIIA liquids unless approved by the fire code official. Exception: Tank vehicles are allowed under weather protection canopies and canopies of automobile motor vehicle fuel-dispensing stations. |
Tank vehicles are to be loaded outside of a building unless approved by the fire code official.
The potential for the accumulation of vapors in a building where the bulk loading of tank vehicles takes place produces an unacceptable hazard.
The exception allows loading tank vehicles under a canopy because a canopy structure is considered to be outdoor usage.
|
5706.5.1.15 Tank vehicle and tank car certification Certification shall be maintained for tank vehicles and tank cars in accordance with DOTn 49 CFR Parts 100-185. |
Tank vehicles for use with flammable and combustible liquids are regulated under DOTn 49 CFR Parts 100-185.
Tank vehicles and tank cars not having a current certification are not to be used.
|
5706.5.1.16 Tank vehicle and tank car stability Tank vehicles and tank cars shall be stabilized against movement during loading and unloading in accordance with Sections 5706.5.1.16.1 through 5706.5.1.16.3. |
The stability of tank vehicles and tank cars is to be maintained during loading and unloading.
The movement of a tank vehicle or tank car during loading or unloading could cause a spill.
|
5706.5.1.16.1 Tank vehicles When the vehicle is parked for loading or unloading, the cargo trailer portion of the tank vehicle shall be secured in a manner that will prevent unintentional movement. |
Cargo trailers must be secured to prevent movement during loading and unloading.
|
5706.5.1.16.2 Chock blocks Not less than two chock blocks not less than 5 inches by 5 inches by 12 inches (127 mm by 127 mm by 305 mm) in size and dished to fit the contour of the tires shall be used during transfer operations of tank vehicles. |
Tank vehicles are to use chock blocks that conform to the wheels to prevent movement.
Movement of the tank vehicle could cause a spill.
|
5706.5.1.16.3 Tank cars Brakes shall be set and the wheels shall be blocked to prevent rolling. |
Tank cars are to use both the tank car brakes and blocks to prevent movement.
Movement of the tank car could cause a spill.
|
5706.5.1.17 Monitoring Transfer operations shall be monitored by an approved monitoring system or by an attendant. Where monitoring is by an attendant, the operator or other competent person shall be present at all times. |
To prevent spillage, the transfer operations are to be continually monitored by an individual at the site.
|
5706.5.1.18 Security Transfer operations shall be surrounded by a noncombustible fence not less than 5 feet (1524 mm) in height. Tank vehicles and tank cars shall not be loaded or unloaded unless such vehicles are entirely within the fenced area. Exceptions:
|
Transfer operations must occur in a fenced-in area to prevent access by unauthorized personnel and the possibility of introducing ignition sources around the transfer operation.
The three exceptions cover special sets of circumstances:
- Motor fuel-dispensing facilities that comply with Chapter 23.
- Installation is approved by the fire code official, who provides security that complies with the intent of the code.
- Facilities or properties that are entirely enclosed or protected from entry by unauthorized persons.
|
5706.5.2 Bulk transfer Bulk transfer shall be in accordance with Sections 5706.5.1 and 5706.5.2.1. |
The operation of a motor vehicle is prohibited during bulk transfer to prevent the presence of an ignition source.
|
5706.5.2.1 Vehicle motor Motors of tank vehicles or tank cars shall be shut off during the making and breaking of hose connections and during the unloading operation. Exception: Where unloading is performed with a pump deriving its power from the tank vehicle motor. |
The engine of a motor vehicle is a source of ignition.
This ignition source must be turned off when transferring flammable or combustible liquids.
The exception allows a motor vehicle’s engine to operate during the transfer of flammable or combustible liquids only if the pump to move the liquids is powered by the vehicle engine.
|
5706.5.3 Process transfer Process transfer shall be in accordance with Section 5706.5.1 and Sections 5706.5.3.1 through 5706.5.3.3. |
Safety features are installed in the processing system to protect the system from failure.
The failure may be caused by operational procedures or equipment.
The process transfer is to be designed and operated to prevent hazards such as leaks, spills, pressure buildup, siphonage, accumulation of vapors and exposure to ignition sources.
|
5706.5.3.1 Piping, valves, hoses and fittings Piping, valves, hoses, and fittings that are not a part of the tank vehicle or tank car shall be in accordance with Section 5703.6. Caps or plugs that prevent leakage or spillage shall be provided at all points of connection to transfer piping. |
Piping complying with Section 5703.6 protects against leaks and overpressures that may create leaks at joints or rupture of the pipes.
Caps or plugs are to be available for all openings to prevent residue from leaking or spilling from the piping system.
|
5706.5.3.1.1 Shutoff valves Approved automatically or manually activated shutoff valves shall be provided where the transfer hose connects to the process piping and on both sides of any exterior fire-resistance-rated wall through which the piping passes. Manual shutoff valves shall be arranged so that they are able to be accessed from grade. Valves shall not be locked in the open position. |
Shutoff valves must be installed to isolate portions of the piping system.
The valves must be located where the flammable or combustible liquids connect to the process equipment.
Valves are to be located on both sides of exterior fire-resistance-rated walls. Valves are not to be locked in the open position.
|
5706.5.3.1.2 Hydrostatic relief Hydrostatic pressure-limiting or relief devices shall be provided where pressure buildup in trapped sections of the system could exceed the design pressure of the components of the system. Devices shall relieve to other portions of the system or to another approved location. |
Pressure relief valves must be installed to prevent damage to the system by releasing the pressure into another portion of the system or to an approved location.
This prevents the vapors from the flammable and combustible liquids from being released into the building or facility’s atmosphere.
|
5706.5.3.1.3 Antisiphon valves Antisiphon valves shall be provided where the system design would allow siphonage. |
An approved antisiphon device must be installed to prevent leakage or spillage by siphoning flammable or combustible liquids from one portion of the process system to another.
|
5706.5.3.2 Vents Normal and emergency vents shall be maintained operable at all times. |
Vents are installed to help prevent overpressurization of tanks and transfer piping.
If these vents fail to operate as designed, serious damage to the system could result.
|
5706.5.3.3 Motive power Motors of tank vehicles or tank cars shall be shut off during the making and breaking of hose connections and during the unloading operation. Exception: When unloading is performed with a pump deriving its power from the tank vehicle motor. |
Because vapors or minor liquid spillage may always present a fire hazard, it is important to remove all possible sources of ignition from the vicinity.
Requiring internal combustion engines to be shut off before connections are made or broken removes an ignition source from the vicinity.
The exception acknowledges that some pumps are powered by the tank vehicle engine involved in the liquid transfer operation.
|
5706.5.4 Dispensing from tank vehicles and tank cars Dispensing from tank vehicles and tank cars into the fuel tanks of motor vehicles shall be prohibited unless allowed by and conducted in accordance with Sections 5706.5.4.1 through 5706.5.4.5. |
This section covers the dispensing of flammable or combustible liquids from a tank vehicle or tank car into the fuel tank of a motor vehicle.