A "confined space" as defined by OSHA, is a space that is large enough so that an employee can bodily enter and perform assigned work, has limited or restricted means for entry or exit, and is not designed for continuous employee occupancy. Examples include (but are not limited to) boilers, tanks, vessels, stills, silos, mixers, storage bins, hoppers, vaults, vats, and pits.

A permit required confined space is a confined space that requires a special permit to enter. These usually contain (or have the potential to contain) a hazardous atmosphere, an engulfment or entrapment hazard, or physical hazards. If any other serious safety or health hazard are present, it may also be classified as permit-required. Some companies even take a step further than the OSHA requirements and choose to treat every confined space onsite as a permit required confined space and follow all processes and procedures pertaining to those types of entries. 

Confined spaces are considered one of the deadliest places in the workplace because of the potential for danger. Many different types of hazards are found in confined spaces. Atmospheric issues can arise, which aren't always apparent. Oxygen is a basic necessity for life, but if there is too much or too little in a confined space, atmospheres can become deadly. Flammable or toxic gases/vapors are sometimes invisible to smell or see, and without proper equipment you would not be able to tell otherwise. Residue of previous chemicals can be left behind, the configuration of the space, the nature of the work, external hazards, and even outside hazards (animals, insects, noise, etc.) are examples of potential dangers surrounding confined spaces and why they are considered dangerous. Confined spaces are also prone to changes in the level of safety at any given time. Perfectly normal, common work conditions can quickly turn into an IDLH (Immediately Dangerous to Life or Health) atmosphere with some help from the hazards listed.

Confined Space Hazard Types

• Oxygen Rich

• Example: Oxygen is greater than 23.5%

• Oxygen Deficient

• Example: Oxygen is lesser than 19.5%

• Flammable Vapors/Gases

• Examples: Possible chemical reactions, combustible dust

• Toxic Atmospheres

• Examples: Carbon monoxide, hydrogen sulfide

• Corrosive Atmospheres

• Examples: Hydrochloric acid, ammonia

• Physical Hazards

• Examples: Ladders, scaffolding, wet surface, poor lighting

• Mechanical Hazards

• Examples: Mixing vessels, falling objects

• Surface Hazards

• Examples: Slips and falls

• Noise Hazards

• Example: Grinding work and loud environments may interfere with communication and delay rescue or emergency services if needed

• Vibration Hazards

• Example: Woodworking tools

• Engulfment Hazards

• Example: Entrapped by contents of a confined space

• Temperature Hazards

• Examples: Heat stroke or heat stress, burns from hot surfaces, and freezing from extremely cold surfaces

• Electrical Hazards

• Example: Hazards from equipment taken into the space

ALWAYS REMEMBER TO LOCK AND TAG OUT EVERYTHING THAT COULD MOVE AND INJURE WORKERS!

Confined Space Rescue

Where a system of entry permits is in place, a rescue plan is required. It will list the personnel and equipment required to be at the worksite before entry is allowed. Special equipment such as tripod hoists, harnesses, and others may be required to extricate a worker from a toxic environment, without unduly endangering rescue personnel.

Whether you are looking for confined space training or rescue, Safety Training Services is here to assist you! Find more information on our confined space training class via our Training Services Page or if you are interested in our Stand-by Rescue Teams, check out our Rescue Services Page for more information!