Application—This manual pipeline sampling procedure
is applicable to liquids of 101 kPa (14.7 psia) RVP or less
and semi-liquids in pipelines, filling lines, and transfer lines.
The continual sampling of pipeline streams by automatic
devices is covered in Practice D 4177 (API MPMS Chapter
8.2). When custody transfer is involved, continuous automatic
sampling is the preferred method as opposed to manual
pipeline samples. In the event of automatic sampler failure,
manual sampling may be needed. Such manual samples should
be taken as representatively as possible.