When you consider the potential for workplace fatalities, wastewater treatment doesn’t spring immediately to mind, but in fact, the possibility of such tragedies is very real due to exposure to lethal amounts of hydrogen sulfide gas. A recent article from Emerson published in Water Online cites two high profile cases.
Last year, two workers died at a wastewater treatment plant in Wichita Falls, Texas, after being exposed to H₂S. Daniel Nix, the manager of utility operations, told the Times Record News “that the workers were conducting routine maintenance on a pump when they were exposed to hydrogen sulfide gas.” He said, “the other personnel at the plants found them and called police and fire emergency responders.”
“In his report, the Freese and Nichols engineering consultant wrote that the most likely cause of hydrogen sulfide buildup in the plant is a combination of a reduction of water use by city residents, a higher concentration of gas-producing bacteria and hot summer temperatures,” per the Times Record News.
In Key Largo, Fla., three utility workers died last year as a result of gas fumes in a drainage trench. The fumes were a combination of H₂S and methane. A firefighter who went in after them was carried away from the site in critical condition. Local sheriff Rick Ramsay described the incident to the Miami Herald as a “stack of dominoes cascading downward.”
The article points out that any number of factors could have changed the outcome of these tragic incidents. But one way to maintain a better understanding of H₂S and manage potential exposure to wastewater employees is to monitor for the gas.
While the article points out a number of possible detection systems, of particular significance is the new wireless detection capability – the Rosemount 928 Wireless Gas Monitor. In some plants, it can be cost prohibitive to install and operate conventional gas detection systems at these sites due to geography and infrastructure. The installation, wiring, and commissioning costs for each additional wired device can add tens of thousands of dollars to the instrument’s total installed cost. Operators have been forced to rely on portable gas detection devices or, even worse, carry on with no gas detection at all. The 928 has a fully integrated, battery-powered wireless monitor. These combined features improve toxic gas leak coverage that keep personnel safe and protect critical assets. Wireless delivers reliable readings, enabling remote collection of field data as frequently as once per minute. With quick and easy installation, the system is up and running in a matter of minutes. Accurate wireless readings keep operators updated on changing conditions remotely – reducing manual operator rounds and improving safety by keeping personnel out of hazardous areas and safeguarding against catastrophic events.
Wireless toxic gas monitoring is making a big difference in safety and efficiency in a wide range of applications.
Have you monitored for toxic gas at your sites? What technology do you use?