Canadian Occupational Safety

20 www.cos-mag.com Canadian Occupational Safety refinery has a large explosion, and the site must be evacuated. In addition to the company's own employees, there are hundreds of contractors on site. Everyone is required to report to a muster area. Since the workers are all wearing hydrogen sulphide (H2S) gas monitors that are connected through wireless technology, the safety team will quickly be able to assess whether everyone has arrived at the muster point safely. "A lot of things on the administrative side are not immediately available in an emergency response," says Nick Randall, technical sales specialist at Calgary-based Concept Controls. "When all these devices are interconnected, it's a matter of just log- ging into the software and seeing where everyone is." In recent years gas detectors have become much more than devices to detect the presence of haz- ardous gases. Wireless, "connected" technology has transformed them into platforms for a vari- ety of functions. Many of these features are useful to safety managers, but it is also important to be aware of the limitations of these new devices. Gas detectors are designed to measure and iden- tify the concentration of certain gases in certain work areas. Typically, they protect workers from exposure to flammable gases, toxic gases and low oxygen concentrations. Detectors are equipped with one or more sensors, which each have a cer- tain life expectancy. Use of gas detectors is highest in industrial facili- ties and is most common in industries such as oil and gas (offshore platforms, onshore refineries and chemical plants), natural gas facilities, steel mills, printing plants, construction, mining and utilities. Cable and phone companies equip their workers with hydrogen sulphide and carbon monoxide (CO) detectors before going into manholes. Gas detectors are also used in commercial build- ings and public facilities, such as retail centres, schools and swimming pools. Flammable detec- tors are used in restaurants. In office buildings, gas detectors measure oxygen and carbon monoxide content, and in parking garages, there are detectors monitoring carbon monoxide levels. Gas detectors have advanced in recent years through the introduction of new sensor technolo- gies, says Michael Douglas, national manager, market segments, at Oakville, Ont.-based Levitt- Safety. For example, infrared gas detection is used today to detect combustible hydrocarbon gases. Photo-ionization detectors (PIDs) use ultraviolet rays to detect volatile organic compounds (VOCs) such as solvents, fuels, degreasers and lubricants, which are used in manufacturing processes and waste handling. Moreover, a single gas monitor today can detect many different hazardous gases. "Back in the coal days of Pennsylvania, LEL (lower explosive limit) monitors were basically looking for methane. They graduated into adding more sensors. You had to buy an oxygen detector and flammable detector separately, and then they combined them into one unit. Then they started adding toxics like carbon monoxide, hydrogen sulphide and chlorine. They evolved into three-gas, four-gas units. Now, with some gas detectors, you can detect up to seven different things with one unit," Douglas says. The biggest change in gas detection today, how- ever, has been the trend among manufacturers to move their products into cloud-based systems, he says. This technology allows a company to manage its gas detection program remotely. Cloud-based systems centre on what is called a docking station. Gas detectors need to be calibrated, a procedure in which a person presents an amount of the hazard to the detector to make sure it is work- ing correctly. Typically, this task is performed by the company that owns the detector. Through the dock- ing station, manufacturers remove this function from the user company. At the end of every shift, each detector is placed into a station, which is con- nected both to the cloud and to the manufacturer, which can then monitor the detector. "What the manufacturer can do through predic- tive technology is to understand, for example, that this particular gas detector has a sensor that is about 25 per cent of the way through its life, and this other one is 75 per cent of the way through its life. So, they will send a replacement sensor for the one that's at 75 per cent directly to the end user (the employer). It will arrive at the end user, and the end user will do the change and send back the old sensor. The manufacturer may even send a brand-new instru- ment," Douglas says. Manufacturers are also incorporating different types of communication protocols into the devices themselves. With this added technology, which may be proprietary, cell or Bluetooth, they can track the unit as it moves through a work site. "Manufacturers are using that type of technol- ogy for various reasons, including the collection of data: how their instruments are being used, what the gas monitor is 'seeing' in the way of blips on the various sensors. They want data about each alarm: Connected technology provides advanced data to maintain gas detectors, reduce worker exposure By Linda Johnson

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