Acceptance tolerance: The tolerance values used when the vehicle scale is first placed in service or returned to service after being repaired or calibrated or after 30 days of being placed in service. Normally acceptance tolerances are half of maintenance tolerances.

Aggrading: Depositing (as opposed to eroding) of material, such as caused by a stream.

ANFO: An explosive material consisting of ammonium nitrate and fuel oil.

Angle of repose: The angle a normal pile of material makes to the horizontal. Used as an indicator of flowability; the steeper the slope, the more sluggish the flow.

Angle of surcharge: The angle to the horizontal a material assumes at rest on a moving conveyor belt. An indicator of flowability.

Approach: The pavement at each end of a vehicle scale leading to the scale platform. There are specific requirements for the size and slope of approaches to vehicle scales.

Arm: Section of an excavator attachment between the boom and the bucket.

Articulated haul truck: Truck with a bed that moves independently from the cab, for use in conditions that are characterized by bumpy, uneven terrain, or ground that is exceedingly soft, slippery or twisty.

Audit trail: An electronic count and/or information record of the changes to the values of the calibration or configuration parameters of a scale.

Automated haul truck: A driverless truck that utilizes automation technology to guide it along a prescribed route at a quarry operation.

Backbreak: Large fragments or blocks of unblasted material dislodged into the muck pile requiring secondary sizing or breaking.

Banana screens: Decks that feature multiple slopes with the deck angles progressively declining from feed to discharge.

Belt conveyor: A mechanical device that uses belts, rollers, pulleys and other hardware to move multiple tons of virtually any material. Perhaps the most easily recognizable of all conveyor types.

Blinding: The clogging or plugging of screen openings by fines material during the production process.

Breakout force: Maximum vertical upward force created by the curling action of a bucket attached to an excavator, loader or backhoe, measured 4 in. behind the tip of the bucket cutting edge.

Bucket: Fitting or attachment to an item of mechanical equipment, such as an excavator, backhoe or dragline that digs, lifts, loads and carries material.

Bucket capacity: Actual volume of material that can be carried in an equipment bucket.

Bumper bolt system: A restraint system employing adjustable bolts located at either end of the weighbridge. These bolts strike adjacent plates mounted to the pit wall or foundation structure preventing excessive horizontal movement of the weighbridge.

Certificate of conformance: See NTEP CC.

Check rod system: A restraint system using multiple rods attached between the weighbridge structure and foundation structure to rigidly check the movement of the scale platform.

Class IIIL tolerances: The tolerance class for vehicle scales used in the United States. The tolerance is shown in Handbook 44 and is a step tolerance allowing one half division of error for each 500 divisions or multiple thereof load applied to the scale platform.

Classifying tank: A rectangular settling tank into which is fed a slurry consisting of sand and water for the purposes of separating out the sand.

Concentrated Load Capacity (CLC): May also be referred to as Dual Tandem Axle Capacity, a capacity rating of a vehicle or axle-load scale, specified by the manufacturer, defining the maximum load applied by a group of two axles with a centerline spaced 4 ft. apart and an axle width of 8 ft. for which the weighbridge is designed.

Control trailer: The nerve center of the crushing spread — the trailer usually contains the control tower, the electrical switchgear and the generator.