OSHA Confined Spaces Advisor

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Many workplaces contain spaces which are considered "confined" because their configurations hinder the activities of any employees who must enter, work in, and exit them. For example, employees who work in process vessels generally must squeeze in and out through narrow openings and perform their tasks while cramped or contorted. For the purposes of this rulemaking, OSHA is using the term "confined space" to describe such spaces.

In addition, there are many instances where employees who work in confined spaces face increased risk of exposure to serious hazards. In some cases, confinement itself poses entrapment hazards. In other cases, confined space work keeps employees closer to hazards, such as asphyxiating atmospheres, engulfment or the moving parts of a mixer, than they would be otherwise.

OSHA uses the term "permit-required confined space" (permit space) to describe those spaces which both meet the definition of "confined space" and pose health or safety hazards.

Asphyxiation is the leading cause of death in confined spaces. The asphyxiation that have occurred in permit spaces have generally resulted from oxygen deficiency or from exposure to toxic atmospheres.

In addition, there have 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. Also, employees working in silos have been asphyxiated as the result of engulfment in finely divided particulate matter (such as sawdust) that blocks the breathing passages.

OSHA has, in addition, documented confined space incidents in which victims were burned, ground-up by auger type conveyors, or crushed or battered by rotating or moving parts inside mixers. Failure to deenergize equipment inside the space prior to employee entry was a factor in many of those accidents.

Many employers have not appreciated the degree to which the conditions of permit space work can compound the risks of exposure to atmospheric or other serious hazards. Further, the elements of confinement, limited access, and restricted air flow, can result in hazardous conditions which would not arise in an open workplace.

For example, vapors which might otherwise be released into the open air can generate a highly toxic or otherwise harmful atmosphere within a confined space. Unfortunately, in many cases, employees have died because employers improvised or followed "traditional methods" rather than following existing OSHA standards, recognized safe industry practice, or common sense.

The failure to take proper precautions for permit space entry operations has resulted in fatalities, as opposed to injuries, more frequently than would be predicted using the applicable Bureau of Labor Statistics models.

OSHA notes that, by their very nature and configuration, many permit spaces contain atmospheres which, unless adequate precautions are taken, are immediately dangerous to life and health (IDLH). For example, many confined spaces are poorly ventilated - a condition that is favorable to the creation of an oxygen deficient atmosphere and to the accumulation of toxic gases.

Furthermore, by definition, a confined space is not designed for continuous employee occupancy; hence little consideration has been given to the preservation of human life within the confined space when employees need to enter it.

It is your obligation as an employer to evaluate your workplace to determine if any spaces are permit-required confined spaces.

The system will next ask questions to determine whether the space constitutes a hazard covered by the permit-required confined spaces rule.