This method is intended for the semi-quantitative determination of ethyl mercaptan odorant (within the range of 5 to 48 mg/L) in liquid propane in order to confirm that recently stenched propane is odorized to the required level. Two procedures are given which are intended for field application and may be suitable for use by non-laboratory personnel after suitable training. A gas chromatographic method should be used for more precise, quantitative determination of ethyl mercaptan in propane.

Other low molecular weight mercaptans, such as methyl mercaptan, can interfere by giving a positive result.

The primary stain tube described in this method is suitable for Grade 1 propane but is not suitable for Grade 2 (commercial) propane, which normally contains more than 5% propylene by volume.

The testing and evaluation of a product against this method require the use of materials and/or equipment that could be hazardous. This document does not purport to address all the safety aspects associated with its use. Anyone using this method has the responsibility to consult the appropriate authorities and to establish appropriate health and safety practices in conjunction with any applicable regulatory requirements prior to its use.