(a) Test method for leak detection:

1. (1) Within four (4) hours prior to monitoring, the organic vapor analyzer or combustible gas detector shall be suitably calibrated in a manner and with the gas specified by the manufacturer for twenty percent (20%) of the lower explosive limit response, or calibrated with methane for a ten thousand parts per million (10,000 ppm) response;
2. (2) The probe inlet shall be two and one-half centimeters (2.5 cm) or less from the potential leak source when searching for leaks; and

3. (3)

   1. (A) The highest detector reading and location for each incident of detected leakage shall be recorded, along with the date, time, and name of the person performing the testing.
   2. (B) If no gasoline vapor is detected, that fact shall be recorded.

(b)

1. (1) Control efficiency of vapor recovery systems and vapor collection/processing systems shall be determined according to EPA Method 2A and either EPA Method 25A or 25B.
2. (2) EPA Method 2B shall be used for vapor incineration devices.

(c)

1. (1) Vapor pressure of gasoline shall be determined using American Society for Testing and Materials (ASTM) Method D323-94 or ASTM Method D4953-93.
2. (2) Method D323-94 shall be used for gasoline either containing no oxygenates or MTBE (methyl ethyl butyl ether) as the sole oxygenate.
3. (3) Method D4953-93 shall be used for oxygenated gasoline.