Confined Space EntryReference Guide (OSHA)

What are confined spaces?Confined spaces are spaces that:

Are large enough and so configured that an employee can bodily enter and perform assigned tasks in the space.

Have limited or restricted means for entry and exit. Are not designed for continuous occupancy by

employees.

What are some examples of confined spaces? Silos. Storage bins. Hoppers, rock boxes and chutework. Tanks. Manholes, pits and vaults.

What are some hazards that would prohibit employees from entering a confined space?

Hazardous atmospheres which may be flammable, toxic or asphyxiating.

Materials that have the potential to engulf. Internal configuration such as inwardly converging

walls, sloping floors and tapering cross-sections that could cause entrapment and/or asphyxiation.

What procedures must be followed when attempting to eliminate a hazardous atmosphere?

Calibrate testing equipment. Without entering the confined space, test the

atmosphere for the following with respect to the acceptable limits listed below: Oxygen Content 19.5% - 23.0% Lower Explosive Limit <10% Carbon monoxide <25ppm Hydrogen Sulfide <10ppm Heat (if applicable)

If atmosphere is not within acceptable limits, but the hazards can be eliminated through ventilation, use forced air ventilation.

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During ventilation process, test the atmosphere without entering the confined space.

Successful elimination of hazardous atmosphere results when all acceptable limits are met.

Document all test results during process. Upon entry, test the atmosphere with continuous-

monitoring equipment or with conventional testing equipment every 15-30 minutes.

What precautions must be followed when entering a confined space such as bins, hoppers, rock boxes, chutework, silos, tanks, etc.?Before entering one of these confined spaces –

The supply and discharge of material to and from the space must be stopped.

All materials in the space that have the potential to engulf an entrant must either be removed or stabilized in such a manner as to eliminate the engulfment hazard.

All equipment (belt conveyors, screw conveyors, feeders, pneumatic pumps, crushers, screens, etc.) that supply and/or control the supply and discharge of material to and from the confined space must be locked and tagged in accordance with established lockout/tagout policies and procedures.

All required personal protective equipment must be donned by persons before entering the confined space.

A safety harness and lifeline must be worn by each person(s) entering the confined space and a person(s) outside of the confined space must be designated to tend the lifelines.

A means of communication between the person(s) entering the confined space and the person(s) tending the lifelines must be maintained at all times while the entrants are in the confined space.

All equipment such as tripods, winches, first aid equipment, etc. that is necessary to ensure the safe and expedient rescue of an incapacitated entrant must be maintained and ready for use in the event of an emergency.

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PERMIT-REQUIRED CONFINED SPACE DECISION FLOW CHART

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