J_3-Error_Table.pdf

J.3 ERROR TABLE

CHECK CRUISE TOLERANCES AND PASSING SCORES

The following check cruise tolerances and passing scores will be used for all forms of check cruising in Region 6. These replace tolerances and scores in FSH 2409.12, Chap. 60, and

Section 62.1 – Exhibit 01.

For the purpose of the Presale Contract, the Cruiser = The Contractor and the Check Cruiser is the Forest Service employee checking Contractors work for payment of work.

SPECIES IDENTIFICATION: No tolerance. Passing score 95%.

POINT/PLOT TALLY: No tolerance. Passing score 95%.

MEASUREMENTS:

DBH: 3% variance from the Check Cruiser’s DBH. Passing score 90%.

i.e., Check Cruiser’s DBH = 37.9, variance = 1.1”.

HEIGHTS: 8% variance from the Check Cruiser’s height. Passing score 90%.

i.e., Check Cruiser’s Total Height = 90 ft. x 8%, variance = 7.2 ft. or 7 ft.

i.e., Check Cruiser’s Merch. Height = 76 ft. x 8%, variance = 6.1 ft. or 6 ft.

The program can also compare Total Height to Merch. Height or Merch. Height to Total Height. Cruiser’s measurement is converted to the Check Cruiser’s height method, and compared to the acceptable range.

TOTAL HEIGHT – VS – MERCH. HEIGHT

Check Cruiser’s Total Height = 100’: Cruiser’s Merch. Height = 82’

DBH=16”, FC=80, Top DIB=5”

Cruiser’s Merch. Height is converted to Total Height.

Converted Total Ht. = Merch. Ht. + Check Cruiser’s Crown Height, which is determined by Check Cruise program, using the NATCRS formula.

Converted Total Ht. = (82’) + 16.4’ = 98.4’

Cruiser’s converted height is compared to the acceptable range.

Acceptable Range = Check Cruiser’s Total Height x 8% Tolerance.

Acceptable Range = 100’ x 8% = 92’-108’.

Cruiser’s converted height of 98’ is within tolerance.

MERCH. HEIGHT – VS – TOTAL HEIGHT

Check Cruiser’s Merch. Height = 82’: Cruiser’s Total Height = 100’

DBH=20”, FC=80, Top DIB=8”

Cruiser’s Total Height is converted to Merch. Height.

Converted Merch. Ht. = Total Ht. – Original Cruiser’s Crown Height, which is determined by Check Cruise program, using the NATCRS formula.

Converted Total Ht. = (100’) – 12.3’ = 87.7’

Cruiser’s converted height is compared to the acceptable range.

Acceptable Range = Check Cruiser’s Total Height x 8% Tolerance.

Acceptable Range = 82’ x 8% = 75’-89’.

Cruiser’s converted height of 88’ is within tolerance but the Top.

TOP DIB: 25% variance from the Check Cruiser’s DIB. Passing score 90%.

i.e., Check Cruiser’s Top DIB = 12” x 25%, variance = 3.0”.

DIB @ 16.5’: 6% variance from the Check Cruiser’s DIB @ 16.5’. Passing score 90%.

i.e., Check Cruiser’s DIB @ 16.5’ = 15” x 6%, variance = 0.9”.

PRODUCT DESIGNATION:

(Grade) Grade 8 (non-saw log) considered a log with defect i.e., Cruiser has grade 1 without defect, Check Cruiser has grade 8 without defect.

Cruiser is out of tolerance

Logs having different product designations will be considered correct, providing the defect deductions are within tolerances, (see defect deductions).

DEFECT:

W/O (without) Defect: A maximum variance of 8% defect deduction is applied when a defect deduction is recorded by one individual (Cruiser or Check

Cruiser), but not both.

i.e., Cruiser has grade 1 without defect, Check Cruiser has grade 1 with 8% defect. Cruiser is within tolerance.

i.e., Cruiser has grade 1 with 9% defect, Check Cruiser has grade 1 without defect. Cruiser is out of tolerance.

i.e., Cruiser has grade 1 without defect, Check Cruiser has grade 8 or 9. Cruiser is out of tolerance.

W/ (with) Defect: A maximum variance of a 15% defect deduction is applied when both Cruiser and Check Cruiser record a defect deduction.

i.e., Cruiser has grade 1 with 25% defect, Check Cruiser has grade 1 with 10% i.e., Cruiser has grade 1 with 10% defect, Check Cruiser has grade 1 with 26% i.e., Cruiser has grade 1 with 46% defect, Check Cruiser has grade 8 without i.e., Cruiser has grade 8 without defect, Check Cruiser has grade 1 with 45% i.e., Cruiser has grade 1 or 8 with 46% defect, Check Cruiser has grade 9. Cruiser is within tolerance.

i.e., Cruiser has grade 9, Check Cruiser has grade 1 or 8 with 45% defect. Cruiser is out of tolerance.