Deadly Sin No. 3 – Use of the Wrong Equipment
Using the wrong equipment is the third sin in Crowcon’s series on the seven deadly sins of gas detection. The best intentions in gas detection can be thwarted if you use the wrong gas detector. There are many ways in which accuracy and safety are compromised, but could have been avoided. Below you will find some examples.
What you need to know about using gas detection equipment
Incorrect choice of sensor technology
To choose the right sensor type, it is necessary to know which gases need to be measured. The local environment can have a critical impact on the sensor’s performance. Consider the choice of sensors for flammable gases:
- Can the sensor be contaminated? Pellistors are generally suitable for detecting flammable gases, such as hydrogen and hydrocarbons. However, the sensor can be poisoned or lose performance if exposed to various chemicals, such as silicone and sulfur-based compounds. In environments where these substances are present, an IR sensor would be a better choice.
- Are there cross-sensitive gases present? An IR-based sensor can be a good choice for detecting hydrocarbons. However, it will not be able to measure hydrogen. For this, an electrochemical sensor is the right choice. But carbon monoxide can cross-react with electrochemical hydrogen sensors, resulting in an inaccurate reading. If both carbon monoxide and hydrogen are present, a pellistor should be considered for detecting hydrogen.
But beyond choosing the best sensor technology, there are many other ways in which the wrong choice of equipment can endanger lives.
Equipment not suitable for the conditions
A good example of this is equipment for offshore environments. Extreme temperatures, strong winds, seawater, ice, and high salt levels make it necessary to use detectors made of suitable materials. Detector heads should be in 316 stainless steel. Other grades of metal will corrode due to the high salt levels from the seawater, and thus the sensors need to be replaced frequently.
Access to confined spaces without a device with a pump
Access to confined spaces, Confined Space Entry (CSE) requires special equipment. A detector without a pump (or aspirator) only measures gases in the immediate vicinity. A pump can take a sample from the confined space before entering. This ensures that people entering the area do not step directly into hazardous conditions.
