SECTION 154
SCALES
154.01 SCALES
A. General.
PSC is defined as the Weights and Measures Division of the Public Service Commission or
a certified scale service.
Have the scale tested and certified by PSC within 6 months before use on the Project.
Before beginning the weighing operation, the Engineer will test the scale. Have the scale
retested by PSC if it is not within the required tolerance.
Do not alter the scale from the manufacturer’s original design unless approved by PSC. Do
not use a scale altered to weigh loads that exceed its rated capacity.
Have testing, certifying, retesting, and weight comparisons of scales performed at no cost to
the Department.
Maintain scales within 1.0 percent of true weight.
Adjust the balance to read zero before weighing each load.
When a pay item has an estimated quantity of 50,000 tons or more, use a Full Length
Electronic Platform Scale (FLEPS) as specified in Section!@# 151.05.B.5 or a Hopper Scale
as specified in Section!@# 151.05.D.
B. Truck Scales.
1. General.
Provide a weather tight building that encloses the recording beams of the scale.
2. Installation and Maintenance.
Install the scale on a firm, level foundation. Maintain sharp, straight knife-edge pivots
and smooth pivot-bearing surfaces. Keep the platform and scale clean to maintain
proper function and accuracy.
3. Platform and Approaches.
If scale platform does not have adequate length to weigh the longest truck or truck-trailer
combination used on the project in one operation, use:
 separate scales whose platforms are at the same elevation and arranged to
permit simultaneous weighing of the entire unit
 single scale that can separate operations provided any wheels not resting on the
scale platform are supported on a concrete or asphalt paved level approach or
on an independent level platform rigidly constructed of wood or steel.
Do not split weigh when a FLEPS is required.
4. Electronic Truck Scales.
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Use an electronic scale with a load cell or cells. Ensure the scales conform to the current
edition of the National Institute of Standards and Technology (NIST) Handbook 44.
5. Full Length Electronic Platform Scales.
Equip the FLEPS with a platform of sufficient length to weigh the longest truck or trucktrailer combination used on the project, in one operation.
C. Hopper Scales.
Use a hopper scale that conforms to the current edition of the NIST Handbook 44. Equip the
Hopper Scale with an electronic digital readout that displays the tonnage being weighed and
will operate continually during weighing operations.
D. Belt Scales.
Use a belt conveyor scale that conforms to the current edition of the NIST Handbook 44.
E. Loader Bucket Scales.
1. General.
Use loader bucket scales with a load cell or cells that conforms to the current edition of
the NIST Handbook 44.
2. Calibration.
At the beginning of the first day of production, perform a calibration test by one of the
following methods:
a. Platform Scale.
Weigh the full and tare weights of three or more sequential trucks on a certified
platform scale. Determine the net weight and compare with the loader bucket
scale weight.
b. Certified Weight.
Use a weighted object:
 at least 60 percent of the maximum weight that will be applied to the loader
bucket scale for the Project
 clean of foreign material
 equipped with a welded-on plate that displays the certified weight
Recertify the object after making changes that affect the certified weight.
G. Scale Tests.
Perform scale tests under the observation of the Engineer. Discontinue use of the scale until
completing adequate repairs when not meeting any one of the following Specifications.
1. Comparison Test.
Recheck weight comparisons not meeting the Specifications after making adjustments.
If the scale has been under-weighing, the Department will compensate for losses.
If the scale has been over-weighing, the Engineer will determine the weight of all
material weighed after the last comparison test meeting the specified requirements. The
Engineer will reduce pay quantity by the percentage of scale error that exceeds one
percent.
a. Truck Scales.
Conduct one of the following comparison tests every 5,000 tons of material weighed
or one day’s production, whichever is greater.
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b. Random Truck Selection.
The Engineer will randomly select a loaded truck weighed on the Project scale.
Weigh the randomly selected truck on another certified scale.
c. Certified Equipment Weight.
Certify the equipment weight at the time the scale is certified. The certified
equipment must be:
 at least 60 percent of the maximum weight that will be applied to the scale for
the Project
 clean and full of fuel
 equipped with a welded-on plate that displays the certified weight
Clean and refuel the equipment each time it used for the weight comparison.
Recheck the weight of the equipment each time the scale is recertified.
Recertify the equipment after making changes that affect the certified weight.
Make weight comparisons on the piece of equipment using another certified scale for
the first two days of operation and once per month thereafter.
d. Hopper Scales.
Conduct one of the following comparison tests every 5,000 tons of material weighed
or one day’s production, whichever is greater. Compare the weight of the material in
the hopper and the weight of the material after it is weighed on another certified
scale.
e. Belt Scales.
The Engineer will randomly select a minimum of one loaded truck for every 1,000
tons of material weighed with a minimum of one test per day. Weigh the randomly
selected truck on another certified scale
f.
Loader Bucket Scales.
Perform daily weight check by one of the following methods:
 The Engineer will randomly select a minimum of one loaded truck. Test as
specified in Section!@# 151.05.F.2.a.
 Using a certified weighted object as specified in Section!@# 151.05.F.2.b
2. Sensitivity Test.
Provide two metal 50 pound test weights certified by PSC. Ensure each weight is
stamped or permanently marked with its certified weight.
a. Truck Scales.
Conduct a weekly sensitivity test by adding the certified test weights to the scale
while weighing a loaded truck. Discontinue use of the scales not sensitive to the
added weight.
b. Hopper Scales.
Conduct a weekly sensitivity test by adding the certified test weights to the hopper
scale after the material is loaded and weighed. Discontinue use of the scales not
sensitive to the added weight.
c. Belt Scales.
Not required.
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d. Loader Bucket Scales.
Not required.
3. Shift Test.
a. Truck Scales.
Conduct a shift test at the beginning of the Project and at least one other time during
the Project.
Check the performance of the scale with off-center loading by comparing the results
obtained by weighing a loaded truck in the following positions:
 centered on the scale platform
 rear wheels at the extreme end of the scale platform
 rear wheels at the extreme opposite end of the platform
Recertify the scale if the results differ by more than 0.2 percent from one another.
c. Hopper Scales.
Not required.
d. Belt Scales.
Not required.
e. Loader Bucket Scales.
Not required.
H. Documentation
1. Weigh Tickets.
Use an automatic printer to print two weigh tickets with a maximum size of 5½ X 8½
inches. Submit weigh tickets when material is delivered to Project.
Program the automated scale system to not print a weigh ticket if a load is 1,000
pounds over the Legal Gross Vehicle Weight. Display an overload message with the
gross vehicle weight.
Program the automated scale system to print a word or symbol identifying manually
entered weight information.
Print the following information on each weigh ticket:
FLEPS
Truck Scale
Belt Scale
Loader
Bucket
Scale
Hopper
Scale
Project
Number
PCN
Date
Time
Project
Number
PCN
Date
Time
Project
Number
PCN
Date
Time
Project
Number
PCN
Date
Time
Project
Number
PCN
Date
Time
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FLEPS
Truck Scale
Belt Scale
Loader
Bucket
Scale
Hopper
Scale
Ticket
Ticket
Ticket
Ticket
Ticket
Number
Number
Number
Number
Number
(consecutive) (consecutive) (consecutive) (consecutive) (consecutive)
Haul Unit
Number
Net Tons in
the Load
Type of
material
Gross
Weight
Tare Weight
Pit Location
Haul Unit
Number
Net Tons in
the Load
Type of
material
Gross
Weight
Tare Weight
Haul Unit
Number
Net Tons in
the Load
Type of
material
Haul Unit
Number
Net Tons in
the Load
Type of
material
Pit Location
Pit Location
Haul Unit
Number
Net Tons in
the Load
Type of
material
Material
Spread
Distance
The Department will allow manual weighing and recording as specified in Section
!@#151.08 B for up to 2 consecutive work days if the printer or control malfunctions.
2. Daily Haul Sheets.
Provide a daily haul sheet for each type of material that lists truck numbers and the net
tons for each load hauled and total tons hauled for each unit.
Print the following information on the daily haul sheet:
FLEPS
Project Number
Subcontractor
Running Total
PCN
Type of Project
Haul Sheet Number
Date
County
Pit Location
Contractor
Material Hauled
Pit Owner
Sign each daily haul sheet certifying that it is true and accurate quantity of material
supplied to the Project and submitted to the Engineer at the end of each day. Provide a
blank line for the Engineer’s signature.
3. Daily Tare Weight Reports.
Determine the tare weights of each hauling unit every day when using a FLEPS. Provide
a daily tare weight report that lists each hauling unit number and its daily tare weight.
Include scale checks documentation with the daily tare weight report.
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