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(a) Each sampling connection system shall be equipped with a closed-purge, closed-loop, or closed-vent system. This system shall collect the sample purge for return to the process or for routing to the appropriate treatment system. Gases displaced during filling of the sample container are not required to be collected or captured.
(b) Each closed-purge, closed-loop, or closed-vent system as required in paragraph (a) of this section shall:
(1) Return the purged process fluid directly to the process line; or
(2) Collect and recycle the purged process fluid; or
(3) Be designed and operated to capture and transport all the purged process fluid to a waste management unit that complies with the applicable requirements of §265.1085 through §265.1087 of this subpart or a control device that complies with the requirements of §265.1060 of this subpart.
(c) In-situ sampling systems and sampling systems without purges are exempt from the requirements of paragraphs (a) and (b) of this section.