The key to reducing risk – spend less time exposed to hazards! Technological advances, driven by increasing safety awareness, are providing opportunities to reduce detector maintenance and therefore also reduce the amount of time operators must spend handling detectors and transmitters in hazardous areas.
Andy, Crowcon’s Senior Product Manager, has reviewed the benefits that these developments bring.
Gas detection has evolved significantly since its earliest days of testing gas levels in hazardous environments with a caged canary! Fatalities have drastically reduced since then with the introduction of more ‘sophisticated’ methods of protection. There is however still an element of risk involved with maintenance, but gas detection technology is evolving to reduce this need and thus operator exposure.
Gas detector maintenance
Conventional fixed detectors require routine calibration to ensure reliable, long term use. A new generation of ‘intelligent’ gas detectors offer ‘bump test’ functions as an alternative to full calibration. On higher-risk sites a full calibration could be performed once every six months, with only a simple bump test in-between. A bump test produces a definitive ‘pass/fail’ that not only enables the engineer to leave the area quickly, but also produces an auditable record that the test was conducted and the sensor was fully operational. Detectors that have non-intrusive calibration eliminate the need to remove the lid, or any other part of the transmitter, making this a much quicker procedure than in the past.
Some widely used sensor types have to be replaced routinely every 2 to 5 years; or more frequently if exposed to extremes of temperature, humidity, gas etc. This often means taking apart the transmitter or sensor housing. If done in a hazardous area this can take a lot of time – especially if PPE (gloves, goggles etc) has to be worn! New ‘Hot-swap’ sensors mean faster replacement, with the most intuitive designs enabling the sensor module to be removed without even having to open the housing. On some units this can also be done using only one-hand – a much simpler job – especially if you need to hold onto a ladder at the same time.
Remote access to data
Gas detectors equipped with Modbus or HART communication protocols can be tested remotely for operating status or fault diagnosis. Whereas the 4-20mA analogue signal may still be used to perform the safety function (i.e. activate sounder and beacons, control gas valves etc), workers can communicate with detectors remotely to get detailed information on the current ‘health’ of the detector. If any faults or issues are found, corrective actions can be properly planned before sending the engineer into the area.
Intelligent gas detectors now offer local displays with a range of diagnostic messages and improved information which greatly reduces the amount of time required to identify faults on site, on the rare occasions they occur. All parameters within the gas sensor and transmitter are constantly monitored and, where an issue that may affect operation or safety is identified, the transmitter will display an appropriate message. This alerts the engineer to the issue and may even prescribe the solution, speeding up the resolution.
The best way to keep people safe is by reducing risk. Now that gas detectors can be monitored remotely, and maintenance planned to significantly reduce the time engineers’ must spend in potentially hazardous areas, we can radically reduce the risks workers are exposed to.
See Andy’s full article on this in Hydrocarbon Engineering Magazine.