What Factors Determine a Confined Space

To define a Confined Space doesn’t have to be difficult. When asked, just remember these 5 rules.

A confined space has any one of the following characteristics:

  1. Spaces that are large enough, and configured in a way that person has no problem when they enter the space to perform work, it’s a confined space. An example of this is an underground tunnel.
  2. If the space isn’t designed for continuous worker occupancy it’s a confined space. In other words, if the space wasn’t developed or designed for people to work inside if it for a long period of time, it might not have the safety features in place to support life.
  1. If the space has limited or impeded openings for people to enter and exit, it’s a confined space.
  2. If the space wasn’t designed for continuous human occupancy, it would be considered a confined space.
  3. Spaces that contain a hazard which may pose an illness or injury, are it’s a confined space. These hazards can be caused by materials or substances present in the space before entry, or by materials brought into the space by a worker completing a task.

So basically, to define a confined space, ask this question: Can you live in it? If not, it’s a confined space.

Planning for Confined Spaces

Identify the hazards in the confined space, which could include:
Atmospheric hazards (lack of sufficient oxygen or breathing air)
Energy source controls (electrical, thermal, pressure, gravitational)
Tools/equipment (within the space or brought in by entrants)
Chemical hazards (within the space or brought in by entrants)
Rescue or protective equipment that restricts movement, or a shaped or configured space where employees could be trapped (tapered end) or engulfed by materials (a grain silo).

All Site Safety and Health Officers should take a Confined Space course and have a certificate to confirm the course has been taken. This course should be retaken anytime there is an update to the EM 385-1-1 or OSHA Standard. Luckily, the updates don’t happen too often!