OSHA 1910.146, the standard covering permit-required confined spaces, is a great starting point to learn more about creating a confined space program. The standard is a quick read, covering the terminology you'll need to know, general requirements, the duties of each person involved in the program, training and rescue and emergency services.
There are several important components to confined space programs, including pre-entry measures, atmospheric monitoring and entry and exit procedures, among others. This article will cover the fall protection components of a confined space program, including general requirements as spelled out in OSHA 1910.146 and appropriate equipment selection.
THE BASICS
Before we jump into the details, it's important to first determine whether your site has a permit-required confined space. OSHA maintains that confined spaces exist in virtually every industry and many workers may come into contact with one during the course of their work. Confined spaces include storage bins, sewers, tanks, silos, stacks, vaults, pits and many more locations that have cramped spaces and narrow openings. OSHA defines a confined space as a location that is large enough and so configured 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.
Not all confined spaces require a formal program; only permit-required confined spaces are regulated by OSHA 1910.146. To be defined as a permit-required confined space, a space must have one or more of the following characteristics:
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Contains or has a potential to contain a hazardous atmosphere;
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Contains a material that has the potential for engulfing an entrant;
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Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section; or
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Contains any other recognized serious safety or health hazard (such as a fall hazard).
If a space is identified as a permit-required confined space and an employee will need access to the space, then the employer must develop a written program that complies with OSHA 1910.146.
Permit-required confined spaces pose serious hazards. Along with difficult access, confined spaces often present problems such as inadequate ventilation or noxious air. It is these conditions, according to OSHA, that result in fatalities, making efficient and immediate exit or rescue from the space imperative. Unfortunately, two-thirds of deaths in confined space rescue situations occur to people trying to rescue someone else. The critical nature of these rescues sometimes leads to poorly planned attempts. Recognition of a permit-required confined space is only the first step in preventing fatalities. Adequate planning, preparation and practice, along with proper equipment, are necessary to keep employees safe while working in and around confined spaces.
GENERAL REQUIREMENTS
The first fall protection consideration when working near or preparing to enter a confined space relates to the access area itself. When a hatch or cover is removed to provide access to a confined space, as is the case with manhole covers, the opening immediately must be guarded with a railing, temporary cover or some sort of barrier to prevent an accidental fall into the space. All workers, not just those entering the confined space, need to be outfitted with fall protection. An employee preparing to conduct atmospheric monitoring inadvertently may become overwhelmed by fumes when the cover is removed, which could result in loss of consciousness. Therefore, it is important for those working near the opening to wear either a restraint lanyard, preventing them from reaching the edge of the opening, or an arrest lanyard or lifeline, to stop a fall in progress, before the cover is even removed.
OSHA 1910.146 only indirectly addresses the need for fall protection equipment in the permit-required confined space standard when, in reference to non-entry rescues, it states in part (k)(3)(i):
“Each authorized entrant shall use a chest or full body harness, with a retrieval line attached at the center of the entrant's back near shoulder level, above the entrant's head or at another point which the employer can establish presents a profile small enough for the successful removal of the entrant. Wristlets may be used in lieu of the chest or full body harness if the employer can demonstrate that the use of a chest or full body harness is infeasible or creates a greater hazard and that the use of wristlets is the safest and most effective alternative.”
Although not elaborated upon directly in 1910.146, fall protection is covered in depth throughout other portions of the 1910 and 1926 (construction industry-specific) standards and thus, is required in confined spaces.
If a vertical entrance into a confined space is required, equipment must be provided to ensure safe access. This usually is accomplished with a ladder or davit arm/tripod along with a winching mechanism. Additional fall protection is required by the regulations and all U.S. manufacturers require the use of fall protection equipment when using davit arms and tripods. If a worker is using a fixed ladder to descend into a confined space, the ladder becomes the primary means of fall protection and a self-retracting lifeline along with a winching mechanism becomes the back-up or secondary means of fall protection.
The same full-body harness required in the event a non-entry rescue becomes necessary also can be used with a personal fall arrest system — it's as simple as attaching the harness to a self retracting lifeline attached to the davit arm or tripod already in use to lower the entrant into the space.
If the concept of fall protection or the use of this equipment is new to an employee involved in the confined space program, or if no training documentation is on file for the employee, the employee must be trained in inspection and use of fall protection equipment as well as general fall protection issues.
EQUIPMENT SELECTION
When selecting fall protection equipment for confined space entry, exit and rescue, there are three main components you'll need: an anchorage, body support and a connector.
If the confined space requires vertical entry, and there is not a fixed ladder, you'll need either a davit arm or a tripod. For task-specific work such as manhole entry, a tripod is a great option. Tripods easily are set-up by one worker and can be transported from one location to another. One limitation of the tripod is the size of the opening it can accommodate.
If more versatility is needed, a davit arm or davit post may be a better option. Davits have a variety of base configurations that make use of the equipment ideal for work at varying job sites. Some have adjustable bases to hoist the worker over larger openings; others are fixed in a “V” shape and placed adjacent to the opening. Both portable and fixed position bases are available for davit systems.
A counterweight system may be needed when access to a confined space does not allow the legs of a tripod or davit arm to be positioned over or adjacent to the entry point. This type of system uses counterweights on one side of the system to balance the weight of a person being lowered on the other side.
If a horizontal entry with vertical positioning or retrieval is required — for example, an opening on the side of a tank — a side-entry system will be required. This type of system clamps or bolts to the access point to provide an anchorage and base for attaching a winching mechanism.
When it comes to selecting body support, comfort and durability are major factors. If your employee will be working in the confined space for an extended period of time or at multiple locations throughout the day, consider a high-quality, full-body harness with built-in shoulder, back and leg padding and soft edging. If durability is a bigger priority, consider a harness with protective coating designed to resist dirt, grease and grime, which wipes clean. Basic harnesses are an extremely economical option for employees who rarely need to access a space or who need access for short periods of time.
Specialized harnesses are available for confined space entry and retrieval. These harnesses have D-rings on the top of both shoulder straps. A device called a Y-lanyard connects these two D-rings to the winch line so the employee can be raised and lowered in a fully vertical position. If attaching the winch line to the dorsal D-ring, the employee will be raised and lowered on a slight diagonal, which can be difficult in very tight spaces.
Finally, for the connector, a winching mechanism will be used. A winch, including a steel or synthetic line and crank to release or recoil the line, connects to the tripod or davit system to lower and raise the employee. The key benefits of using a winch include mechanical advantage, allowing one employee to easily lower and lift another, and a braking system. Should the winch operator let go of the crank, the person being raised or lowered will not fall.
An optional feature on some winches, a power drive makes frequent raising and lowering procedures easier on workers. The winch still has manual capabilities, but offers the option of automatically powering the mechanism.
Proper equipment to perform quick, safe rescue is essential in any operation where confined spaces must be entered. Typically, the safest and most effective fall protection systems include self-retracting lifelines. These lifelines should be integrated with a retrieval system in all confined space entry situations; this allows the entry attendant to perform a non-entry rescue, should it become necessary.
PREVENTING TRAGEDY
Talking about safety in confined spaces is good, but there may be no better indication of the need for confined space safety equipment than an example. One year ago this month, workers at a landfill in Superior, Wisc., were trying to fix a faulty pump at the bottom of a manhole. One worker was at the bottom of the hole when he was overcome by hydrogen sulfide fumes. Another worker went down the hole to attempt to rescue him, but he was overcome as well. Another worker followed, then a fourth. All four men tragically died trying to rescue one another.
These types of deaths are preventable. Had the workers been using gas detection devices and wearing harnesses connected to a winch or self retracting lifeline with rescue capabilities, the early warning could have given the entry attendant and other workers enough time to engage the winch and perform a non-entry rescue.
Safety in permit-required confined spaces is not to be taken lightly. Identifying potentially hazardous spaces and putting together a written program is required by law. Furthermore, proper equipment selection and training along with practice entering, exiting and performing rescues is necessary to keep employees safe while working in and around confined spaces.
Charley Bryant is product manager for hardgoods, and Jim Hutter is senior training specialist for Capital Safety (http://www.capitalsafety.com).