Definition(s)
Blow-down
The rapid controlled or accidental depressurization of a vessel or piping network.
Source: API RP 2FB, Recommended Practice for the Design of Offshore Facilities Against Fire and Blast Loading, First Edition, April 2006. Global Standards
Blow Down
To vent off gas in a well.
Source: IADC UBO / MPD Glossary, December 2011. Global Standards