Reference
Definition
What the word means. This is not a work instruction.
Shaft work involves vertical openings, fall hazards, fire-rated assemblies, riser support, alignment, access, and coordination between floors. It can be dangerous and expensive when wrong.
Open shafts are not regular work areas. Fall protection, rigging, communication, and approved supports matter.
This term belongs to rated, life-safety, grease, or structural work. Knowing the word is fine. Doing the work is a red-lane call — get direction before you touch it.