The term "confined space" is intimidating in itself. It brings up thoughts such as closets and elevators and small, tight areas. We have all had those times in our lives when we felt uncomfortable because we were in a small space.
When we look at the term "confined space" as it applies to safety and industry it takes on an even more serious tone. When I think of confined spaces in an industrial setting, I think of entering storage tanks and underground pits, places a person wouldn't normally enter.