The Equipment You Need for a Confined Space Rescue
In many cases, having the right equipment can allow you to rescue a worker without entering the confined space.
A confined space is a space that has not been designed for continuous human occupancy but is still large enough for your employees to enter. It has limited or difficult means of entry and exit, making a rescue operation difficult in the event of an emergency.
If these spaces present various physical and atmospheric hazards, such as materials that can engulf the employee or tapered walls that could lead to asphyxiation, then OSHA defines the space as a permit-required confined space. Permit required confined spaces are regulated by OSHA standard 1910.146 and are immediately dangerous to life or health.
Given the atmospheric hazards, the difficulty of access and egress, working in confined spaces is heavily regulated. Workers performing the work in them must wear specialized equipment and monitor the atmosphere. The employer also needs to have a rescue plan, rescue materials, and a rescue team in place.
Confined space rescues are rarely easy. That's why it's so important that rescuers have quick and easy access to all the equipment they'll need to perform a speedy and safe rescue.
The Equipment You'll Need for a Confined Space Rescue
The most common and known devices and equipment used in confined space rescue are the ones used for non-entry, high angle rescue where the victim is already connected to the retrieval system.
- Winches or self retractable lanyards with a retrieval mechanism
- Rescue harnesses
These are the ones we'll focus on in this article. However, I should note that not all confined spaces are vertical or suitable for non-entry rescue. Tanks, vessels, tunnels, equipment housing, and others will place the victim on a horizontal plane with the entry point and at considerable distances from it.
In those cases, the only option is for rescuers to enter the confined space and bring the victim to safety.
For these rescues, additional rescue equipment is required, such as:
- Self Contained Breathing Apparatus (SCBA)
- Stretcher or backboard
- Static ropes
- Pulleys and swivels
Tripods and Davit Arms
Tripods are the backbone of the non-entry rescue system.
The three legs of the tripod provide a stable platform but limit the access around the entry point of the confined space. To mitigate this inconvenience, tripods are fairly tall, generally nine feet or greater. Often, the three legs are connected to each other at the base, through a chain or bar.
Davit arms serve the same purpose but only block the entrance to the confined space on one side. They are designed like a crane and reach over the entry point of the space. Their adjustable base allows them to be configured around a diversity of entrances. Some also have a swivel arm that allows rescuers to effortlessly turn and move the victim on the solid ground, which is another advantage over tripods.
Tripods and Davit Arm systems used for confined space rescue should meet the specifications of ANSI/AASP Z359.1, as well as comply with OSHA confined space (1910.146) and fall protection (1910.132) standards.
Self Retracting Lanyards with Rescue Capability
The most common retrieval device by far is the self retractable lanyard with rescue capabilities (SRL-Rs).
Although they are included in the same standard with the other SRL devices (ANSI Z359.14), these devices should not be confused with regular self-retracting lanyards (SRL-P) or leading-edge models (SRL-LE), since SRL-Rs are not designed only to arrest a fall, but also to retrieve an injured employee by raising or lowering them.
These devices have a large mechanical advantage when in retrieval mode, usually in the range of 30:1, ensuring the rescuer has the physical ability to retrieve the victim.
The switch from arresting an employee to retrieving varies from model to model, but it is generally very quick and simple, allowing the rescue to start almost immediately after the incident.
It should be noted that the SRL-Rs capabilities are generally only used when an incident happens. The employee will typically enter or exit the confined space under their own power, generally by climbing a ladder.
Rescue winches are devices that have raising and lowering capabilities but don't arrest a fall.
Winches are practical when there are no access ladders. The employee is lowered into the confined space with the winch and raised to the surface when the work ends or if a rescue is required.
To protect the employee in case the winch fails, they should also be attached to a fall protection system, usually an SRL.
Other Considerations for Retrieval Devices
It is recommended that there should be a backup system in case the first system becomes unusable due to malfunction, entanglement, or the victim getting stuck. Many tripods and davit arms provide attachments for a secondary device, allowing them to immediately attach a rescuer and quickly switch from a non-entry rescue to an entry rescue.
Some fall protection harnesses are specifically designed for rescue operations. However, the rescue harnesses used in confined space entry and rescues are not usually different from those used in fall protection.
Typically, the employee is attached to the self-retractable lanyard through the dorsal D-ring (sometimes through the ventral D ring). This is acceptable in many scenarios, but if you need to raise a victim who has lost consciousness, attaching them at this point will result in their head deviating from the vertical. This could cause their head to hit the walls in the rescue process. It would also complicate extraction through a small opening, such as a manhole.
When using an SRL-Rs, it can be attached directly to the spreader bar.
When using a combination winch and SRL, the winch line used for the rescue should be attached to the spreader bar. The SRL, which will be used exclusively for fall protection, should be attached to the ventral or dorsal D-ring.
Time is of the essence when rescuing a worker from a confined space. All employees who might perform a confined space rescue should be trained on how to choose, set up, and use the rescue equipment.
Performing drills is great practice. It also allows you to test the functionality of your equipment and the capability of your personnel. Make sure to run through them ahead of time so you can fix any potential issues before you have to deal with a real-life rescue scenario.