N.Y. Comp. Codes R. & Regs. tit. 16, § 400.14 – Testing of pressure compensated counters.

(a) The counter shall be tested by applying pressure to the compensating mechanism and rotating the “following” magnet a fixed number of turns as shown in the following table with two readings being taken at each of the test pressures. Should the results of the two tests at any of the test pressures, one taken with the pressure being increased to the test point and the other with the pressure being decreased, vary by more than one percent, additional pairs of tests shall be taken until such agreement is reached. The average of the readings obtained shall be deemed to be the condition of the counter.
(b) If more than four additional pairs of tests are required, the test shall be considered “indeterminate.”
(c) The accuracy at each test point shall be determined by the following formula:
Percent Registration =^{Observed Revs. of Counter × 100}/₄
Pressure in Psig. No. of Magnet Turns Correct No. of Counter Turns
87½ 29 4
125 25 4
186 21 4