StacksVerified U.S. regulatory reference

40 CFR Part 205, Appendix I

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov
Batch sizeCode letter
4 to 8A.
9 to 15B.
16 to 25C.
26 and largerD.
Sample size code letterTest sample | Test sample size | Cumulative test sample size | Batch inspection criteria
Acceptance No.Rejection No.
A1st | 4 | 4 | 0 | 1
B1st | 3 | 3 | 0 | 1
C1st | 3 | 3 | 0 | 2
2d | 3 | 6 | 1 | 2
D1st | 2 | 2 | (1) | 2
2d | 2 | 4 | (1) | 2
3d | 2 | 6 | 0 | 2
4th | 2 | 8 | 0 | 3
5th | 2 | 10 | 1 | 3
6th | 2 | 12 | 1 | 3
7th | 2 | 14 | 2 | 3

1 Batch acceptance not permitted at this sample size.

Sample size code letterNumber of batchesCumulative number of batchesSequence inspection criteria
Acceptance No.Rejection No.
A221 | (2)
242 | 4
263 | 5
284 | 5
B220 | (2)
241 | 4
262 | 5
283 | 5
2104 | 6
2125 | 6
C22(1) | 2
240 | 2
260 | 3
281 | 3
2102 | 4
2123 | 4
D220 | 2
241 | 3
262 | 4
283 | 4

1 Batch sequence acceptance not permitted for this number of batches.

2 Batch sequence rejection not permitted for this number of batches.

Test Report Number:Manufacturer:
VEHICLE:
Trade Name:VIN:
Model Year:Other Reference No:
Configuration Identification:Category Identification:
Test Site Identification and Location:
INSTRUMENTATION:
Microphone Manufacturer:Model No:Serial No:
Sound Level Manufacturer:Model No:Serial No:
Calibrator Manufacturer:Model No:Serial No:
Other and Manufacturer:Model No:Serial No:
TEST DATA:
Approach Gear:Date of Test:
Approach RPM:Temp:Wind:

Acceleration Test: |

Deceleration Test: |

Run No.
123 | 4 | 5
dBALeft | | | |
Right | | | |
Highest RPM attained in End Zone | | |
Calculated Sound Pressure| dBA | | |

Deceleration Test with Exhaust Brake Applied

dBALeft
Right
Calculated Sound Pressure| dBA
TEST Personnel:
(Name)
Recorded By:Date:.........
(Signature)
Supervisor:Title:.........
(Signature)

[41 FR 15544, Apr. 13, 1976, as amended at 42 FR 61460, Dec. 5, 1977]