Michael K. Napier Sr. - Napier Diversified Services, LLC.

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AAR: Abbreviation for Association of American Railroads.
Ad Valorem Tax: A charge levied on persons or organizations based on the value of transaction. It is normally a given percentage of the price of the retail or manufacturing stage and is a common form of sales tax; e.g. Federal excise tax on new trucks and trailers
Adapter, Cam & Groove: The male portion of a quick coupling device for pipe or hose ends.
Adapter, APR: A spring loaded shut-off valve mounted on the tank trailer designed to mate with the terminal loading device. API RP 1004 specifies dimensions for these adapters.
Adapter, Openable Bottom Loading: A bottom loading adapter that is capable of being used to unload a product.
Aerator: A device for adding diffused air into the tank for the purpose of aiding the flow of dry product during unloading.
API: Abbreviation for American Petroleum Institute.
Appurtenance, Cargo Tank: See 49 CFR 178.345-1 (c).
ASME: Abbreviation for American Society of Mechanical Engineers.

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Backhaul: Refers to a load of freight which permits a trucker to return to his home with a loaded truck, rather than an empty one.
Baffle: See 49 CFR 178.345-1 (c).
Baffle, Dished: A baffle with a concave/convex surface.
Barrel, Tank: Vessel weldment - shell and heads.
Bill of Lading: An itemized list of goods contained in a shipment
Billing: Preparation of the freight bill, the primary document for a common carrier shipment including a description of the freight, number of pieces and charges
Bogie: An auxiliary axle assembly having a fifth wheel used for purpose of converting a semitrailer to a full trailer. Dollies can be used to haul multiple trailers behind a single power unit. (Also referred to as dolly)
Blower: A device to deliver a volume of air at a certain pressure for use in unloading pneumatic tanks.
Break Bulk: To separate a composite load into individual shipments and route to different destinations
Break Bulk Terminal: A terminal designed to act as an intermediate sorting point for interregional freight. Freight from various end-of-line terminals is sent to a regional break bulk terminal to be combined into full trailers that the carrier then routes to a subsequent end-of-line terminals. Example: freight destined for Texas from a Binghamton, NY terminal might go to Stroudsburg, PA to be combined with other freight destined for Texas from other Eastern cities.
Brake Interlock, Parking: A system that applies the parking brakes upon actuation of an air interlock valve. This valve is typically actuated during the loading or unloading operation.
Bulkhead, Dished: A bulkhead with a concave/convex surface.
Bulkhead, Double: Two adjacent bulkheads forming a void space. Typically found when the bulkhead of one tank is next to the bulkhead of another tank. The area between the bulkheads typically forms a void.
Bulkhead, Flangeless Tank: An internal bulkhead that is formed with neither a knuckle radius or straight flange.
Bulkhead, Tank: See 49 CFR 178.345-1 (c) and 49 CFR 393.86.
Burner: Gas or liquid fueled burner for heating product in the tank.

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Cap, Dust: Cover which mates with a male adapter.
Cap, Pipe: A cap which mates with the male threads of a pipe and which forms a liquidtight seal.
Capacity, Commodity: Total internal volume that does not include planned outage.
Capacity, Nominal: That compartmental volume to which a vessel is designed that does not include the planned stage.
Capacity, Shell: The absolute full capacity of a tank shell.
Carload: Single shipment of freight required to fill a rail car
Certification, Design: See 49 CFR 178.320 (a).
Certificate Holder: See Holder, Certificate
CFR: Acronym for Code of Federal Regulations.
Christmas Tree: See Vent.
Claim: (a) A demand made upon a transportation company for payment, due to loss or damage of freight alleged to have occurred while shipment was in possession of carrier.; (b) A demand upon a transportation company for refund of an overcharges from the erroneous application of rates, weights, and assessment of freight charges
Class I Motor Carriers *: Common or contract motor carriers of property that have average gross operating revenues of $5,000,000 or more annually from motor carrier operations
Class II Motor Carriers *: Common or contract motor carriers of property that have average gross operating revenues of $1,000,000 or more , but under $5,000,000 annually from motor carrier operations
Class III Motor Carriers *: Common or contract motor carriers of property that have average gross operating revenues of less than $1,000,000 annually from motor carrier operations
Class I Truck: Truck with gross vehicle weight (GVW) of 6,000 lbs or less
Class II Truck: Truck with gross vehicle weight (GVW) of 6,001-10,000 lbs
Class III Truck: Truck with gross vehicle weight (GVW) of 10,001-14,000 lbs
Class IV Truck: Truck with gross vehicle weight (GVW) of 14,001-16,000 lbs
Class V Truck: Truck with gross vehicle weight (GVW) of 16,001-19,500 lbs
Class VI Truck: Truck with gross vehicle weight (GVW) of 19,501-26,000 lbs
Class VII Truck: Truck with gross vehicle weight (GVW) of 26,001-33,000 lbs
Class VIII Truck: Truck with gross vehicle weight (GVW) of 33,001-10,000 or more lbs
COFC: Container on (rail) flat car. A form of intermodal movement of freight using a box suitable for use on rail cars, trailer frames, and container ships Containers come in many sizes. International containers which are used on ships usually have height and width of eight feet. Length can vary, but 20 and 40 foot lengths are the most common. US domestic containers are generally taller than international containers and may not always be suitable for ocean transportation.
Combination Vehicle: An equipment configuration which includes separate power unit (tractor) and at least one trailer
Commercial Trailer: A trailer used to handle freight in the transportation of goods for others; excludes house trailers, light farm trailers and car trailers
Commodity: Any article of commerce. Goods shipped
Common Carrier *: A transportation business that offers service to the general public. Interstate common carriers must hold a franchise issued by the ICC which limits service to a specific geographical area. Recent changes in regulation have blurred the distinction between common, private, and contract carriers. Term may be meaningless in the near future.
Competitive Rate *

A charge established to meet the competition of another transportation line

Connecting Carrier

A carrier which interchanges trailers with another for completion of shipments.

Contract Carrier *

For hire carriers which proved transportation under specific contracts or agreements that do not fall within the legal boundaries of common carriage. Recent changes in regulation have blurred the distinction between common, private, and contract carriers. Term may be meaningless in the near future.

Cock, Shut-Off
A device used to restrict or stop flow of air or liquid.
Compartment, Tank
The product carrying space of a tank motor vehicle. A cargo tank motor vehicle may have one or more such spaces. (See Tank, Cargo)
Compartment, Void
See Void Compartment.
Connection, Air
Fitting used to apply air pressure from source to vessel.
Connection, Loading/Unloading
See 49 CFR 178.345-1 (c).
Coupling, Pipe
See 49 CFR 178.345-1 (c).
Coupler, Cam & Groove
The female portion of a quick coupling device for pipe or hose ends.

CWT
Hundred weight, or one hundred pounds

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Dam, Manhole: See Manhole, Dam
Deflector: A device placed inside a tank to change the flow direction during loading or unloading.
Degas: To purge compartments, voids, piping and components of dangerous vapors rendering the cargo tank safe for both hot and cold work.
Dip Stick: A separate measuring device used to determine the level of product in a tank.
Dip Tube: (1) A piping arrangement installed in a tank which will be pressure unloaded out of the top. (2) May also be a tube installed in a pressurized containers to gage the level of liquid.
DOT: Abbreviation for Department of Transportation.
DOT Specification: See Specification, MC/DOT.
Doubler Plate: A reinforcing pad, ring, collar or strap used to reinforce the shell or head.
Drain: A hole, pipe of hose used to gravity discharge liquid from an enclosed area such as a void, void compartment or manhole dam.
Drain, Flashing: See Flashing Drain

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Emergency Valve: See Valve, Emergency
Engineer, Design Certifying: See 49 CFR 171.8.

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Fill Cover, Spring Loaded: A fill cover designed to meet the requirements for the pressure-actuated vent in MC 306 cargo tanks, 49 Code of Federal Regulations, 178.341-4 (d) (2) and DOT 406 cargo tanks, 49 Code of Federal Regulations, 178.346-10 (d).
Fill Opening: An opening in top of a tank used for filling the tank. Usually incorporated in Manhole Cover. It may also be used for inspection.
Fire Tube: See Heating Tube.
Fitting, Clean Out: Fitting installed in the top of a tank to facilitate washing of the tank interior.
Fitting Guard: A structure to protect pipe fittings from damage.
Fitting, Terminal: The end fitting on a line.
Flange: See 49 CFR 178.345-1 (c).
Flange, Companion: See 49 CFR 178.345-1 (c).
Flange, Welded: See 49 CFR 178.345-1 (c).
Flash Point: Means the temperature at which the substance gives off flammable vapors which, in contact with a spark of flame, will ignite.
Flashing: Liquidtight rail on top of a tank which contains water and spillage and directs it to suitable drains, and may be combined with the overturn protection.
Flashing Drain: Metal or plastic tube which drains water and spillage from flashing to the ground.
Float Control: A switching device which opens a circuit when product being loaded into a tank reaches a pre-determined level.
FMCSA: Acronym that stands for Federal Motor Carrier Safetty Administration
FMCSR: Acronym that stands for Federal Motor Carrier Safetty Regualtions, one of the most referenced set of publicaitons in the transport industry

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Gas Free: See Degas.
Gauge, Liquid Level: A device used to measure liquid commodity levels inside a cargo tank.
Gauge, Rotary: A gauge for determining the liquid level in a pressurized tank.
Girth Seam (A Circumferential Joint): A welded joint around the entire circumference or partially around the circumference of the cargo tank joining two sections of the tank shell.

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Head: (1) See Bulkhead, Tank. (2) Also terminology for pressure of a liquid caused by its own weight.
Head, Hemispherical: A head which is half a sphere in shape. Often used on MC 331 compressed gas cargo tanks and MC 338 cryogenic liquid cargo tanks.
Header: A pipe, tube, etc., that connects two or more pipes or tubes permitting the transfer of vapors or liquids to a common outlet. (Also see Manifold).
Heat Panel: A panel attached to the cargo tank\0xD5s shell by welding, bonding or banding used to heat the contents. May also be called steam panel.
Heating Tube: A tube installed inside a tank which is used to heat the contents. May also be called "fire tube" when the direct heat source is a flame.
Holder, Certificate: A moisture proof container provided for storage and easy access to trailer related literature such as licenses, registration, defect and maintenance information. (Formerly called Registration Holder and Defect Card Holder)
Hood, Vapor Recovery: A collecting device installed over tank vents or vapor valves for transfer of vapors during tank loading or unloading.
Hopper: Sloping panels at bottom of tank which direct dry bulk solids to the outlet piping.
Hose, Air Jumper: Hose connecting the truck tractor air supply to a trailer air line or hose.
Hose Carrier: Hose tube, hose trough, hose tube ends and hooks, mandrel and bracket.
Hose, Discharge: Hose used to unload the tank.
Hose Hooks: Hooks which carry the hose.
Hose Trough: An open type structure used on tank and bulk commodity trailers for the storage of cargo handling hoses.
Hose Tube: A housing used on tank and bulk commodity trailers for the storage of cargo handling hoses.

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Indicator, Liquid Level: A device, usually a float or spew gauge, for determining the level of the product in a tank.
Indicators, Capacity: Device installed on tank to indicate capacity at a specific level. (Sometimes called markers).
Inspection Agency, Authorized: See 49 CFR 171.8.
Inspector, Authorized: See 49 CFR 171.8.
Inspector, Registered: See 49 CFR 171.8.
Interlock, Parking: See Brake Interlock, Parking

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Jacket: A metal cover which protects the tank insulation.

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Label, MC/DOT Tank Certification: See Plate, MC/DOT Tank Certification.
Lading, Hazardous: See 49 CFR 178.345-1 (c).
Line Aeration: Line supplying air to the Aerator.
Line, Blowdown: A line through which tank air pressure is released by means of the blowdown valve.
Line Charging: See 49 CFR 178.345-1 (c).
Line Crossover: Installed in tank piping system to allow unloading from either side of tank.
Line, Pipe: A product inlet or outlet line.
Line, Pump Off: A pipeline which usually runs from the tank discharge openings to the front of the trailer. Most pumps are mounted on the tractor.
Line, Vapor Recovery: A line which connects the vapor recovery hood to a convenient location for attachment to a vapor recovery hose.
Lining: The material applied to the inside of a tank shell surface to protect the tank shell from its contents.

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Manhole: An opening usually equipped with removable cover and large enough to admit a man into a cargo tank or dry bulk trailer; may incorporate vents, fill opening and other devices.
Manhole, Dam: Liquid tight box for the collection of spillage (also called spill box, flashing box or crows nest).
Manifold: Used to join a number of pipelines to a common inlet or outlet. (Also see Header).
Manufacturer, Cargo Tank: See 49 CFR 178.320 (a).
MAWP: See Pressure, Maximum Allowable Working.
MC Specification: See Specification, MC.
Modification: See 49 CFR 180.403.

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Nameplate: The NHTSA certification label containing the manufacturer\0xD5s name and vehicle identification number or for cargo tank vehicles manufactured prior to the NHTSA certification plate containing the manufacturer\0xD5s name and cargo tank serial number. (See Plate, MC/DOT)
Nozzle, Tank: See 49 CFR 178.345-1 (c). The pipe or tubular section of the nozzle is short and may be threaded instead of flanged.

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Outage: The space that remains unfilled in a cargo tank after being loaded with payload.
Outlet: See 49 CFR 178.345-1 (c).
Outlet, Loading/Unloading: See 49 CFR 178.345-1 (c).
Outlet, Vapor: The terminus of the vapor recovery line.
Outrigger: Structural load-carrying members attached to and extending outward from the main longitudinal frame members of a tank trailer, which cradle the tank shell or stiffeners. Sometimes called Cradle End.
Overturn Protection: Protection for fittings on top of a tank in case of rollover. May be combined with flashing rail or manhole dam. Also known as Rollover Damage Protection. See 178.345-8 (c) for DOT 400 Series cargo tanks.

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Pads: A piece of material attached to the tank shall to which various attachments are made.
Pipe: See Line, Pipe.
Plate, MC/DOT Tank Certification: (As required by the Research and Special Programs Administration) Metal plate permanently affixed to a cargo tank and located near the front left side of the cargo tank stating that the cargo tank conforms with all applicable Federal Hazardous Materials Regulations in effect on the date of the original manufacture or modification.
Platform: Area on top of the tank near the manhole designed for a person to stand upon.
Pressure, Inspection: See 49 CFR 178.345-1 (c).
Pressure, Maximum Allowable Working: See 49 CFR 171.8 and 178.345-1 (c).
Pressure, Test: See 49 CFR 178.345-1 (c).
Protection, Bottom Damage: Device which protects outlets and piping located in the lower one-third of the cross section perimeter from damage during an accident. See 178.345-8 (b) for DOT 400 series cargo tanks.
Protection Device, Rear-End Tank: See 49 CFR 178.345-1 (c). (Also see Bumper, Rear).
Protection Overturn: See Overturn Protection.
PSIA: Pressure expressed in pounds per square inch absolute. Add approximately 14.7 to gauge reading to give absolute reading.
PSIG: Pressure expressed in pounds per square inch gauge. Gauge pressure is the difference between atmospheric pressure and pressure being measured.
PTO: Abbreviation for Power Take Off.

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Rebarrelling: See 49 CFR 180.403.
Repair: See 49 CFR 180.403
Replacement Barrel: To completely replace the vessel weldment of an existing cargo tank with a newly manufactured vessel weldment using only new materials.
Ring Stiffener: Structure encircling the tank either inside or outside the tank shell to maintain the shape of the tank and its structural stiffness when under pressure/vacuum.
Rollover Protection: See Overturn Protection
RP: Abbreviation for Recommended Practice.
Rupture Disc (A frangible vent): A safety device which fails at a predetermined pressure and thus protects a pressure vessel from being over pressurized. (Also see Vent).

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Sacrificial Device: See 49 CFR 178.345-1 (c). (Also see Shear Section).
Seam, Girth: See Girth Seam.
Sensor, High Level: A liquid actuated sensor installed in a secondary shut-off system. Also, this sensor is sometimes used as a primary shut-off system. The signal from this sensor stops the loading pumps or closes the emergency valve upon overfill. (See Shutoff System, Secondary).
Sensor, Liquid Level: See Indicator, Liquid Level.
Sensor, Retained: A liquid actuated sensor installed in the bottom of a compartment to indicated the presence of liquid.
Shear Section, DOT 400 Series Cargo Tanks: See 49 CFR 178.345-1 (c). (Also see Sacrificial Device).
Shear Section, MC 300 Series Cargo Tanks: A machine groove located outboard of an emergency valve seat and within 4 inches of the vessel which should break under strain and leave the emergency valve seat and its attachment to the vessel and the valve head intact and capable of retaining product.
Shell, Tank: See 49 CFR 178.345-1 (c).
Shutoff System, Secondary: A system that provides overflow protection during bottom loading.
Slope: Difference in height between highest and lowest points of the tank bottom.
Slope Sheet: Panels located at each end or side of compartment which direct product by gravity to hoppers.
Specification, MC/DOT: The U.S. DOT Motor Carrier Specification for tank vehicles authorized to carry specified hazardous materials.
Splash Guard: A device which deflects road spray.
Stack: The exhaust pipe for tanks with burners.
Steam Panel: See Heat Panel.
Stick, Dip: See Dip Stick.
Stiffener, Ring: See Ring Stiffener.
Stretching: See 49 CFR 180.403.
Structure, Connecting: See 49 CFR 178.345-1 (c).
Subframe: The frame to which the undercarriage is attached.
Sump: See 49 CFR 178.345.1 (c).
Sump, Cleanout: The low point of a tank which may be opened for cleaning.
Swivel Joint: A movable metallic product transfer conductor usually used on discharge lines to eliminate the bending or twisting of hoses.

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Tank: See 9 CFR 178.345-1 (c).
Tank, Cargo: See 49 CFR 171.8 and 178.320 (a).
Tank Design Type: See 49 CFR 178.320 (a).
Tank, DOT 406: Tank built after October 1, 1990, meeting US DOT specifications DOT 406 as defined in 49 Code of Federal Regulations 178.346. This tank is typically used to carry gasoline, fuel oil, alcohol, or other liquid flammables. This tank is typically constructed of aluminum and designed with an elliptical cross section.
Tank, DOT 407: Tank built after October 1, 1990, meeting US DOT specifications DOT 407 as defined in 49 Code of Federal Regulations 178.347. This tank is typically used to carry solvents, plasticizers, casinghead, gas, etc. This tank is typically constructed of stainless steel or aluminum and designed for pressure of at least 25 psig.
Tank, DOT 412: Tank built after October 1, 1990, meeting US DOT specifications DOT 412 as defined in 49 Code of Federal Regulations 178.348. This tank is typically used to carry corrosives. This tank is typically constructed of stainless steel or carbon steel and designed for a pressure of 35 psig.
Tank, Dry Bulk: A tank typically constructed of aluminum or carbon steel to carry dry bulk commodities such as cement, fertilizer, sand, plastics, grain, etc. with typical densities ranging from 18 to 125 pounds per cubic feet. This tank is typically designed for an unloading pressure of 15 psig.
Tank, Frac: A portable storage tank used to hold flushing or fracing fluid at an oil well site. Characterized by a large, rectangular cross section, a single axle suspension, no landing gear, and a front winching bar.
Tank, Fuel: Tank used to hold fuel for the burners.
Tank, Hot Products: A tank typically insulated to handle asphalt and other products at a temperature over 300\0xA1 F. This tank is typically constructed of aluminum, steel, or stainless steel and designed for atmospheric pressure.
Tank, MC 304: Tank built prior to December 1, 1967 to old US DOT Specifications MC 304 for the transportation of flammable liquids or poisonous liquids. This tank was constructed of steel and aluminum with a design pressure of at least 25 psig. This tank is a predecessor of the MC 307 tank.
Tank, MC 305: Tank built prior to December 1, 1967 to old US DOT Specification MC 305 for the transportation of flammable liquids or poisonous liquids. This tank was constructed of aluminum and designed for atmospheric pressure. This tank is a predecessor of the MC 306 tank.
Tank, MC 306: Tank built after December 1, 1967 and prior to April 21, 1994, meeting US DOT Specification MC 306 as defined in 49 Code of Federal Regulations 178.341. This tank is typically used to carry gasoline, fuel oil, alcohol, or other liquid flammables. This tank is typically constructed of aluminum and designed for atmospheric pressure. This tank is a predecessor of the DOT 406 cargo tank.
Tank, MC 307: Tank built after December 1, 1967 and prior to April 21, 1994, meeting US DOT Specification MC 307 as defined in Code of Federal Regulations 178.342. This tank is typically used to carry solvents, plasticizers, casinghead gas, etc. This tank is typically constructed of stainless steel and designed for a pressure of at least 25 psig. This tank is a predecessor of the DOT 407 cargo tank.
Tank, MC 311: Tank built prior to December 1, 1967 to old US DOT Specification MC 311 for the transportation of corrosives. This tank was constructed of steel or aluminum. This tank is a predecessor of the MC 312 tank.
Tank, MC 312: Tank built after December 1, 1967 and prior to April 21, 1994, meeting US DOT Specification MC 312 as defined in 49 Code of Federal Regulations 178.343. This tank is typically used to carry corrosives. This tank is typically constructed of stainless steel of carbon steel and designed for a pressure of 35 psig. This tank is a predecessor of the DOT 412 cargo tank.
Tank, MC 330: Tank built prior to December 1, 1967 to old US DOT Specification MC 330 for the transportation of compressed gases. This tank was typically constructed of quenched and tempered or carbon steel for a pressure of 250 to 265 psig. This tank is a predecessor of the MC 331 tank.
Tanks, MC 331: Tank meeting US DOT Specification MC 331 as defined in 49 Code of Federal Regulations 178.337. This tank typically used to carry anhydrous ammonia, propane, or other liquefied or pressurized gases. This tank is typically constructed of quenched and tempered or carbon steel and designed for a pressure of 265 psig.
Tank, MC 338: Tank built after October 1, 1984, meeting US DOT Specification MC 338 as defined in 49 Code of Federal Regulations 178.338. This tank is insulated and designed to carry cryogenic liquids.
Tank, Non-Spec: A tank not meeting one of the US DOT Specifications.
Tank, Sanitary: A tank typically insulated to carry milk, vinegar, vegetable oils, syrups, and other food products. This tank is typically constructed of stainless steel and designed for atmospheric pressure.
Tank, Self Supporting: A tank trailer whose shell is the structural support member for the vehicle.
Tank, TOFC: A tank meeting Association of American Railroads Specification M-931, Appendix F. This tank is a MC 307, MC 312, DOT 407, DOT 412 or IMCO Type 4 tank constructed of steel with a minimum design pressure of 35 psig. This tank trailer is for trailers on railroad flat car service.
Tank, Vacuum: Tank equipped with a pump to reduce the pressure in the tank to much less than atmospheric pressure. This reduced pressure of \0xD2vacuum\0xD3 is used for loading the tank. (See Tank, Waste). Also see 49 CFR 178.345-1 (c).
Tank, Variable Specification: See 49 CFR 178.345-1 (c).
Tank, Washout: A tank holding solvent for cleaning pump and discharge hose.
Tank, Waste: Tank designed to transport waste consisting of liquid and/or solids. Tank may have a full opening rear head. Tank may be equipped for vacuum loading.
TB: Abbreviation for Technical Bulletin.
Toughness of Material: See 49 CFR 178.345-1 (c).
Transition: That section of a tank which joins two unequal cross sections.
Tube, Dip: See Dip Tube.

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Valve, Blow Down: A manually operated valve whose function is to quickly reduce tank pressure to atmospheric.
Valve Box: See Fitting Guard.
Valve Check: A valve built to provide free fluid flow in one direction only.
Valve, Crossover: A valve which allows the discharge to be directed to either side of the tank via the crossover line.
Valve, Emergency: A remote controllable valve installed in a tank outlet sump or its companion flange which is capable of self-closing in the event of an emergency. Also known as Valve, Internal Self-Closing Stop.
Valve, Emergency, Operator: A device used to open and close emergency valves.
Valve, Emergency, Remote Control: A secondary closing means, remote from tank discharge openings, for operation in event of fire or other accident.
Valve, Excess Flow: A valve which automatically closes at its rated flow of gas or liquid.
Valve, Internal: See Valve, Emergency.
Valve, Internal Self-Closing Stop: See 49 CFR 178.345-1 (c). Also known as Valve, Emergency.
Valve, Loading/Unloading Stop: See 49 CFR 178.345-1 (c).
Valve, Outlet: The valve which is farthest downstream in a tank piping system to which the discharge hose is attached.
Valve, Outlet Stop: See 49 CFR 178.345-1 (c).
Valve, Pressure Relief: Valve with predetermined start to discharge pressure to protect the tank from being over-pressurized. (Also see Vent, Pressure Actuated).
Valve, Product: Valve for holding or releasing product into or out of the tank.
Valve, Proportioning: A valve used to balance or divide the air supply between the aeration system and the discharge manifold.
Valve, Pump Off: Valve on pump-off line which when open allows the product to be pumped out of the tank.
Valve, Sampling: Valve which when open allows a sample of product to be collected.
Valve, Self-Closing Stop: See 49 CFR 178.345-1 (c).
Valve, Self Contained Shut Off: An emergency valve that closes upon receiving a signal from the high level sensor.
Valve, Shuttle: A connective valve which selects one of two circuits, whichever supplies the higher pressure.
Valve, Splitter: A valve installed to divide pipeline manifold.
Valve, Stop: See 49 CFR 178.345-1 (c).
Valve, Vapor Recovery (See Vent, Vapor Recovery): A valve typically found in a vapor recovery system to control the flow of vapors. Also a vent that opens and closes with the actuation of the emergency valve permitting the transfer of vapors when in the open position. (Typically opens inward into the tank compartment).
Valve, "Y": A valve which can be used for both bottom loading and off-loading. Incorporates American Petroleum Institute standard adapter.
Vapor Free: See Degas.
Vehicle, Cargo Tank Motor: See 49 CFR 171.8 and 49 CFR 178.320 (a).
Vehicle Assembly, Cargo Tank Motor: See 49 CFR 107.502.
Vehicle, Multi-Specification Cargo Tank Motor: See 49 CFR 178.345-1 (c).
Vent: Devices which control or limit tank pressure. Some type are: 1. Outbreathing (pressure relief) 2. Inbreathing (vacuum relief) 3. Fusible (opens at elevated temperature) 4. Christmas tree (slang for a combination vent) 5. Rupture disc ( See Rupture Disc)
Vent, Overflow: Vent on hot products tanks for overflow of product due to surge and/or expansion.
Vent, Pressure Actuated: A normally-closed, spring-loaded vent for pressure protection. Required on MC 306 cargo tanks, 49 Code of Federal Regulations, 178.341-4-(d); MC 307 cargo tanks, 178.342.4 (c); MC 312 cargo tanks, 178.343-4 (a); DOT 406 cargo tanks, 178.346-10 (d); DOT 407 cargo tanks, 178.347-10 (d); and DOT 412 cargo tanks, 178.348-10 (d).
Vent, Vacuum Breaker: A spring-loaded normally closed vent for vacuum protection.
Vent, Vapor Recovery: A vent that opens and closes with the actuation of the emergency valve permitting the transfer of vapors when in the open position. (Typically opens outward from the tank compartment).
Vents, Normal: A pressure-vacuum vent specified in 49 Code of Federal Regulations, 178.341-4 (b) and (c) and required in each MC 306 compartment and may be installed in each DOT 406 cargo tank.
Void: An enclosed space in a vessel which does not contain product and has no manhole. Also see 49 CFR 178.345-1 (c).
Void Compartment: A void equipped with access manhole.

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Walkway: That portion top of a tank designed for personnel to walk on.
Wall, Cargo Tank: See 49 CFR 178.320 (a).
Weight per Gallon, Allowable: The maximum density, as pounds per gallon, of products which be loaded into a given tank without exceeding the load limits of the tank container or tank trailer.
Weldment, Vessel: The entire tank vessel and welded appurtenances such as nozzles, manholes, flanged and threaded fittings, etc. Bolted-on appurtenances are not included.

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Macon, GA, USA
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