Five Common Confined Space Myths

August, 2014

Nearly every industry contains tight spaces that are considered “confined” because their configurations hinder the activities of any worker who must enter, work in, and exit them. For rulemaking purposes, the Occupational Safety and Health Administration uses the term “confined space” to describe such areas. Not only do confined spaces vary in size, shape and location, but often they present challenging conditions, from limited movement or hazardous air to the risk of engulfment. For example, workers who work in process vessels generally must squeeze in and out through narrow openings and perform their tasks while cramped or contorted.

OSHA identifies more than 20 major sectors of industry and labor with various types of confined spaces, including: Tanks, Hoppers, Vaults, Pits, Vessels, Silos, Storage bins, Manholes, Tunnels, Equipment housings, Ductwork, and Pipelines. Even though confined spaces aren’t necessarily designed for human access, workers are required to go in and perform their jobs day after day. Creating and maintaining a safe job site in and around confined spaces depends on having correct, current equipment and information.

Recognizing real threats verses five common misconceptions.

Test your confined space knowledge:

#1: Falls aren’t an issue in confined spaces?

Confined spaces warrant the same level of fall protection consideration as above-ground work at height. Workers at height require fall protection for obvious reasons, but accidental falls can—and do—occur in confined spaces. To determine whether a confined space warrants the use of fall protection equipment, it’s crucial to evaluate the access point as well as the actual confined space. A manhole is one example of a confined space that doubles as a fall hazard. Lack of proper safety equipment places all workers at an increased risk of falling through the unguarded opening as soon as the cover or hatch is removed. Once inside the confined space, the risk of falling deeper often exists. Falls while entering and exiting confined spaces are common, often caused by old and outdated climbing structures, poor lighting, and challenging space restrictions. In some situations, fumes can trigger loss of consciousness, affecting workers who enter the space or work near the area.

#2: All confined spaces require a permit.

While cramped, tight spaces are found on almost every job site, only spaces that meet OSHA’s definition of a confined space and contain health or safety hazards require a permit. A thorough evaluation of the confined space, including atmospheric monitoring, should be conducted prior to any entry. To require a permit, OSHA specifies that a confined space must meet one or more of the following conditions:

Contains or has the potential to contain a hazardous atmosphere, Contains a material that has the potential to engulf an entrant, Has walls that converge inward or floors that slope downward and taper into a smaller area that could trap or asphyxiate an entrant, Contains any other recognized serious safety or health hazards such as unguarded machinery, exposed live wires, or heat stress. If a worker will be accessing a confined space with any of these circumstances, the employer is responsible for developing a written safety program to comply with OSHA standards (1910.146) prior to starting any work. The written program needs to discuss the means, procedures, and practices used to eliminate or control hazards and to ensure safe operations. In addition to preventative measures, the program should address air quality monitoring, exit and entry methods, and fall protection/rescue systems.

#3: Permit-required confined spaces only require adequate identification and marking?

While clearly marking permit-required confined spaces is an essential step, appropriate signage isn’t the only action you’ll need to take. OSHA’s standard for an acceptable permit spaces program (29 CFR 1910.146(d)), further dictates that entry must be controlled and limited to authorized persons, regulated by a written entry permit system (entry permits must be recorded and issued for each entry into a permit space), and be monitored by an attendant outside the space. The standard also specifies strict procedures for evaluation and atmospheric testing of a space; rigorous training requirements; specific duties for authorized entrants, attendants, and supervisors; and rescue service provisions. It’s crucial to identify physical hazards prior to entry and to test and monitor for oxygen content, flammability, toxicity, or explosive hazards as necessary both before and during entry. Maintaining contact with a trained attendant at all times, either visually, via phone, or by two-way radio, is vital to staying alert and evacuating as quickly as possible in case of emergency.

#4: Non-entry rescue is always the best solution for a confined space rescue?

Hazards of confined spaces, including oxygen-deficient air, toxic and/or flammable gases, difficult entry and escape, and potential engulfment, non-entry rescue can be the safest solution for all parties involved. Although non-entry rescue is usually preferred, determining the smartest and safest rescue approach largely depends on the situation. In many cases, confined space rescue situations can be too complex and dangerous for a non-entry rescue performed by an entry attendant with minimal training. Emergency service or industrial entry teams have more in-depth training and use specialized equipment necessary to save a worker trapped in a confined space. Keep in mind the only time an entry rescue should be performed is when non-entry rescue poses a greater hazard to the worker.

On some job sites, there is already an in-house team trained to provide confined space rescue and emergency services. Many employers think that if they have a competent rescue team on site, they won’t ever need to use non-entry rescue. Actual confined space rescues are stressful, physically demanding, incredibly dangerous, and, depending on the severity of the situation, may warrant non-entry rescue.

#5: Confinement is the most dangerous threat of confined space work?

OSHA has documented confined space incidents in which victims were burned, dismembered by auger type conveyors, or crushed by rotating or moving parts inside mixers. Failure to disconnect power from equipment inside the space prior to employee entry was a factor in many of those accidents.

In some cases, confinement alone poses the most danger, namely the risk of entrapment. In other cases, confined space applications place workers closer to additional hazards, including asphyxiating atmospheres or the moving parts of a machine. Asphyxiation is the leading cause of death in confined spaces. The asphyxiations that occur in permit spaces generally result from oxygen deficiency or from exposure to toxic atmospheres. There have also been cases where employees who were working in water towers and bulk material hoppers slipped or fell into narrow, tapering discharge pipes and died of asphyxiation due to compression of the torso. During silo work, employees have been asphyxiated as the result of ingesting finely divided particulate matter (such as sawdust) that blocks the breathing passages.

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