confined space

Definition

Dangerous or potentially dangerous work area, with only restricted openings for entry and exit that would make an emergency escape difficult. Contributory factors that make a confined space more dangerous include (1) lack of ventilation, (2) contents that are known or potential hazards, (3) underground location, (4) location inside a tank or container, and (5) location in a space not intended for prolonged human occupancy. Typical safety hazards of confined spaces are insufficient oxygen, chemical fumes or vapors, and the possibility of being trapped due to insufficient means of exit.