What does a derrickhand do?

A derrickhand works up on the rig's derrick (the tall structure above the rig floor), guiding pipe into and out of the mast during tripping operations, and is also often responsible for maintaining the rig's mud (drilling fluid) system — monitoring fluid properties and additives that keep the well under control while drilling. It's typically a step up from floorhand/roughneck in a drilling crew's progression, requiring more specific technical knowledge of the mud system and more comfort working at height than an entry-level rig-floor role. Most derrickhands moved into the role after time spent as a floorhand learning rig operations from the ground up, rather than being hired directly into it. Exact responsibilities and how the role is structured vary by drilling contractor, so what one company calls a derrickhand's duties may differ somewhat from another's.