Construction workers regularly perform tasks in confined spaces. The physical and atmospheric hazards can cause serious injuries - however, they can be stopped if addressed prior to entering the space to perform work, per OSHA. Confined spaces are any space by design that has very limited natural ventilation, which could produce dangerous air contaminants, and has a small opening for entry and exit. Both employees and workers need to be trained and a written program must be established for employees and other workers to view. All confined spaces must be considered dangerous and marked as such. The terms "permit-required confined space" and "permit space" refer to spaces that meet OSHA's definition of a "confined space" and contain health or safety hazards. For this reason, OSHA
requires workers to have a permit to enter these spaces. The manhole, crawl space, and tank could be very unsafe and must be identified with a sign, guard, cover, or barrier.