Active Standard: D1945 - 03(2010)
ASTM Headquarters is mandating a review of standards that use mercury and determine if its use is still appropriate, or if it should be removed, or replaced with a non-mercury alternative. D1945 includes a mercury manometer to monitor the pressure of the gas sample loop. Safer modern alternatives exist such as digital manometers and absolute pressure transducers. Section 5.11 has been rewritten to allow any type of vacuum gauge (including mercury manometers). Figure 1 has been replaced with a diagram containing a generic pressure indicator. References to pressure in mm Hg have been removed and replaced with the SI unit Pascal. The mercury changes were approved by main committee ballot in May, 2014. At that time it was discovered that section 1.2 contains faulty language and requires that the method is further revised to comply with current ASTM standards. Rather than publish a new revision which includes a known error, the committee agreed at the June 2014 meeting to halt publication until section 1.2 is corrected. A change to section 1.2 also requires changes to the units used throughout the method. To remain compliant with ASTM standards, only two options exist: 1) Remove all inch-pound units throughout the method and replace with SI units where applicable 2) Provide inch-pound equivalents for all SI units throughout the method. Due to the relatively few cases where inch-pound units are used, this ballot revision seeks to remove all inch-pound units and replace them with SI units. The changes necessary to remove mercury from the method that were approved but not published, are still present in this ballot for consideration.
Keywordsgas analysis; gas chromatography; natural gas composition