To work safely in a confined space, the person entering the area must have a monitor and a lifeline, according to the Mine Safety and Health Administration. In addition, workers must test air quality for adequate oxygen, as well as the presence of flammable gases.
A monitor for the person entering a confined space should be in position to remain unaffected by possible adverse atmospheric conditions of the space, while the lifeline is in place to pull the worker to safety if the need arises, explains the Mine Safety and Health Administration. Neither the worker entering the space nor the monitor should enter the space without proper safety and personal protective equipment, such as the lifeline. Workers should ensure positive airflow through the use of a fan or other equipment, especially when welding or performing other duties that may deplete oxygen or generate harmful gases.
The Occupational Safety & Health Administration defines confined spaces as those spaces not designed for people but large enough for workers to enter to perform certain jobs. These spaces have limited or restricted entry and exit access. Confined spaces include tanks, silos and storage bins, as well as tunnels, pits and pipelines. Some confined spaces put workers at risk of exposure to hazardous atmospheres or conditions that may lead to asphyxiation. OSHA classifies these spaces as "permit-required confined spaces."