Workers entering confined spaces have many health and safety risks to consider. That’s why it’s critical to recognize and plan appropriately for working in confined spaces.
The general definition of a confined space is an area that:
- is large enough for an employee to physically enter and perform work
- has limited or restricted means of entry or exit
- is not designed for continuous human occupancy, or
- has the potential for significant hazards to be present.
Before starting work in confined spaces, employers must carefully identify and assess the hazards to determine which precautions to take. For full compliance with any applicable Federal and/or Provincial Regulations, it’s necessary to rely upon the expertise of safety and health professionals such as industrial hygienists.
Any worker entering a confined space must follow the appropriate procedures. It’s especially important if there is a reasonably foreseeable risk of serious injury in entering or working in the confined space.
Fall protection is one element of a confined space program.
What fall protection equipment is necessary for confined space?
Confined space entry and retrieval equipment may be necessary to facilitate both entry into and exit from confined spaces. Proper retrieval systems for both workers and equipment consist of:
- full-body harness
- tripod or davit systems, and
- appropriate connecting devices.
Retrieval equipment helps lower workers into confined spaces as it controls descent rate and prevents accidental falls into the work area.
Workers can use additional work hoists to raise and lower tools and equipment.
Entrants should always wear a full-body harness and have some kind of lifeline attached to the harness – even in horizontal entry applications. If an entrant becomes non-responsive, non-entrants can use the lifeline to haul the worker out. This is called a non-entry rescue.
Should a non-entry rescue be necessary, lifting equipment uses physics concepts to raise entrants out of work areas. Hoists typically have a mechanical advantage of 25:1. It is complicated for an average person to pull someone out of a deep manhole without some mechanical advantage.
Tripods and davit arms:
Tripods and davit arms should be equipped with two mechanical devices for confined space entry:
- A hoist for raising and lowering materials and personnel, and
- A self-retracting lanyard (SRL) with emergency rescue capability for backup fall protection and emergency retrieval.
The confined space entrant should be connected to an SRL with an emergency rescuer feature. The SRL gives the entrant freedom to move within the confined space and without a topside attendant constantly paying out/retracting the cable line on a hoist as the entrant moves around. If the attendant must rescue the entrant, the topside attendant will activate the emergency rescue feature of the SRL and retrieve the entrant without entering the confined space.
A wide variety of approved harnesses are available for use with retrieval equipment. Shoulder, back, or chest D-rings/loops may be used as retrieval line attachment points. For confined space emergencies with extremely tight openings, a spreader bar is an ideal solution providing both comfort and security when lowering and lifting workers.
Proper inspection and training:
Before each entry into confined space work areas, a qualified person should inspect all equipment.
Workers should not use any equipment that shows signs of wear, damage or doesn’t pass the inspection.
Due to various risks and the variety of equipment in use, all personnel involved in confined space entry, including supervisors, entrants, attendants and rescue personnel, should be well trained.
Individuals authorizing confined space entry must have complete knowledge of the space’s contents and hazards. All confined space workers must fully understand their duties before entry or if there are changes in assigned duties or confined space applications.