Confined space safety ( Part One)

 

 What entrants need to know: testing and monitoring, protection, and rescue

 A confined space is defined as a space that is large enough for a worker to enter, is not designed for continuous worker occupancy, and has limited open­ings for entry and exit. Types of confined spaces include storage tanks, process vessels, boilers, sewers, tunnels, underground utility vaults, pipelines, storm drains and ship void spaces. Some confined spaces can be open-topped, including pits, degreasers, water tanks, ship holds and trenches.

Prior to introducing its standards on confined spaces, OSHA reviewed industry incidents and statistics to deter­mine what was needed to develop standards. What the agency found when studying confined space fatalities was that:

• 89% of fatalities occurred with jobs authorized by supervisors.

• 80% of fatalities happened in locations that had been previously entered by the same person who later died.

• In 40% of fatal atmospheric accidents, the hazard was not present at the time of initial entry.

• 35% of those who died were supervisors.

• Only 7% of locations had warning signs indicating that they were confined spaces.

Sixty-five percent of confined space fatalities are due to atmospheric hazards. The remaining 35% are due to factors such as electrical shock or electrocution, being caught in or crushed by machinery, engulfment,

 falls inside the confined space, and ingress or egress accidents.

Confined space entry poses a number of safety chal­lenges for employers and workers. One is the fact that most confined spaces are unique, having distinct charac­teristics and potential hazards. As such, employers must conduct a thorough assessment of each confined space in order to ensure worker safety.

“Some people aren’t even aware that they need to be testing before they enter confined spaces,” notes Shaun Endsley, industrial/military regional manager for Scott Safety. “As a result, one of the things we like to do is increase awareness among customers by educat­ing them on confined-space rules and regulations. We want them to understand what the hazards and proper procedures are.”

Hazards can vary by industry, according to Endsley. “For example, petrochemical companies have to deal with many tank-cleaning jobs, which involve toxic chemi­cals. On the other hand, municipal wastewater facilities are must deal with problems associated with H2S (hydro­gen sulfide).” 

Testing & Monitoring: Gas Detection 

According to Mel Gerst, product line manager, portable gas detection, for Scott Safety, it is important to test the entry to a confined space before you enter it. “You want to test for oxygen depletion, explosive gasses and toxic gasses, in that order,” he states.

In many cases, entrants do not know they need to monitor the environment of the confined space they are entering. Also, they may not have the proper equipment on hand or in proper working order to properly monitor. Gas monitors must be designed to be easily carried with the entrant, either in their hand or with a robust clip that can attach to a work belt or clothing. If calibrating the gas monitor is complicated, it rarely will be completed, which contributes to improperly functioning equipment.

Best practices in using gas detection equipment include “zeroing” your monitor every day before use, “bump testing” it before use and making sure it remains calibrated. (Scott Safety recommends calibrating every 30 days.) 

 

Scott Safety’s Protege Multi-Gas Monitor is well-suited for confined spaces. Featuring a small, compact design, it fits ergonomically in your hand, so you can operate it with one hand while holding a sampling probe in the other. It allows you to hold the monitor in one hand while recording readings on the confined space permit. For hands free operation the Protégé has a robust “alliga­tor” clip so the unit can be attached to a belt or work clothing for use as a personal monitor.