What Kind of Confined Space Gas Detector Do I Need?
Before entering a confined space, workers need to check the environment to make sure it is safe. Confined spaces often harbor toxic or explosive gasses. They may also be lacking in oxygen. Gas detectors serve as a first line of defense in determining the safety of an environment.
The most important feature to look for in a confined space gas detector is 4 gas detection. This means it can detect and measure CO2, O2, H2S and combustible gasses. CO2 and H2S are highly toxic to humans. O2 (Oxygen) is required for human life; and no one wants to be working in a combustible environment with a high danger of explosion.
The second characteristic to look for is whether it is a diffusion or pump model. This describes how the gas monitor samples the air that it is testing. A diffusion model is passive and only samples air that comes in contact with the sensors. This means if you want to sample a confined space before you enter it, you need to find a way to get the air to the gas monitor. Some folks tie a string to the monitor and drop the monitor into the confined space. This is a terrible idea because confined spaces are often filled with water other hazards that can quickly destroy the monitor. A much better alternative is to sample the air with a separate, manual aspirator pump (squeeze bulb) and a sampling hose. (Try our Confined Space Kit.)
Pump versions of 4 gas monitors do not have this issue. They contain an internal pump that can pull remote gasses out of the confined space and over the sensors for monitoring. When hooked to a sampling hose, most decent ones can pull air from over 70 feet away. This means the sampling hose can be dropped into the confined space without danger to the worker or the monitor. Because of this convenience, pumped 4 gas monitors are used in roughly 80% of confined space entries. If you’re in the market for a 4 gas pump monitor, try the Honeywell Gas Alert Max XT