- Buyer's guide
Dealing With Confined Space A Complicated Challenge
With the answers to these questions, it is possible to move on to further evaluation which would involve the correct use of gas monitors to determine atmospheric conditions before and during the conduct of the work. Employees must know to trust the monitors and exit the space if alarms sound.
Having evaluated the site, the employees should then undertake the appropriate measures to eliminate the hazards...the “Eliminate” step.
Some sites may be so hazardous or contaminated that specialty companies used to dealing with permit-required confined spaces and the use of advanced equipment such as air line supply respirators or self-contained breathing apparatus (SCBA) equipment may be required.
However, most sites, unless they contain contaminated soils, may be well within the capabilities of a typical construction crew, particularly when they involve excavations.
Once all potential sources of engulfment have been identified and locked out or found to be secure and free of leaks, the focus can shift to preventing the buildup of harmful gases. Carbon monoxide generation by equipment used in the excavation might occur, as may the infiltration of CO2 from passing traffic. An employee trained about the hazards of CO2 usually is receptive to wearing the appropriate respirator or helping ensure adequate ventilation occurs.
A knowledge of OSHA standards previously cited is helpful in a scenario such as this.
In the preamble to the General Industry Confined Space Standard, the telecommunications industry could demonstrate a record of more than 50,000 safe entries into manholes and vaults without one fatal incident. Most phone technicians say they seldom use gas monitors in ordinary circumstances, but a blower or ventilator is one piece of equipment they use with religious fervor.
“Simply stated,” Pettyjohn says “it’s tough to beat taking a safe atmosphere in with you. Understanding how to correctly position and use blowers to provide sufficient fresh air in a potential confined space could easily eliminate most confined space concerns, as well as provide cooling on hot summer days. Implementation of a blower on other construction sites easily could be as effective as it has proven to be for the telecommunications industry.”
The OSHA Excavation Standard requires attention to rescue procedures be addressed. Therefore serious consideration must be given to effective means of performing rescue operations, and especially those that can be performed without entry to the danger zone by additional personnel.