Definition(s)
Back up
Refers to the act of “backing up” or preventing rotation of one section of pipe or rods while another is screwed out of or into it. Also applied to screwing nuts on or off bolts. A backup wrench refers to any wrench being used to hold the pipe, rods, or bolt. Backup tongs refers to the pipe tongs suspended in the derrick and used to hold a section of pipe while another section is screwed out of or into it by use of other tongs. The backup man is the crew member who operates the backup tongs. The backup position refers to the workstation of the backup man.
Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global Standards