Air quality is important for everyone, but it is of special concern for those who must work in confined spaces.

A total of four farmer deaths in hog manure pits in July in the Midwest show how even a routine job in a confined space can turn tragic. In the first in incident, in Wisconsin, a father and son were killed from exposure to toxic gases while trying to retrieve something dropped into a manure pit. In the more recent case, in Iowa, another father and son died from exposure to toxic gases when one attempted to rescue the other. Although the incidents occurred in agricultural operations, they illustrate the potential for the rescuers of the initial victim overcome by toxic gases in a confined space to become victims also.

Such pits can release methane, ammonia, and carbon dioxide as well as hydrogen sulfide when disturbed, risking exposure that can lead to unconsciousness and death. Farm safety experts commonly recommend the use of some form of breathing apparatus when working in that environment for those reasons.

Some other examples of confined spaces include storage tanks, sewers, manholes, tunnels, ship voids, pipelines, silos, wells, and trenches. A permit-required confined space has to have one or more specific characteristics, one being that it contains a hazardous atmosphere. These are classified into three categories: toxic; asphyxiating; and flammable or explosive atmospheres. Depending on the chemicals present and their concentration, such environments can present multiple atmospheric hazards.

For those reasons, it is recommended that employers in a number of industries test and monitor their confined spaces at multiple levels with instruments that will detect aspects of hazardous atmospheres encountered by anyone who plans to enter. The ability to perform non-entry rescue is also critical to prevent the loss of would-be rescuers. This involves the entrant wearing a full body harness connected to a confined space-applicable retrieval device mounted outside the space, so that the attendant can remove an unconscious entrant without having to enter the confined space.

The practice of atmospheric testing in confined spaces to determine potential hazards is not new – bringing a caged canary into a coalmine is perhaps the best known example from history. Today’s testing equipment and procedures skip the canary, but they serve a similar purpose. Modern sensor and battery technology has improved the reliability of these instruments and has made them easier to use at a lower price point. For the occasional user, they can be rented from a number of safety equipment rental companies. This approach is sound since the rental companies will maintain and calibrate the instruments as recommended by the manufacturer. Using an unreliable and out-of-calibration toxic and combustible gas meter can almost be worse than using none at all since a faulty meter may provide a false sense of security.

Workplace Safety & Health Co. is equipped to identify and assess the hazards of suspected confined spaces in your facility, determine whether each meets the OSHA criteria for a confined space, and if so, whether it should be permit-required. Workplace Safety & Health Co. can also pre-test the atmosphere in accessible spaces to provide advanced warning that additional precautions may be needed prior to entering a confined space.

With our experience in assessing thousands of confined spaces in a wide range of industries, Workplace Safety & Health Co. can help your organization attain a “best practice” level of compliance. Give us a call or visit our website today to learn more.