The potential danger of gas is that it can be present without any indication (by sight or smell). We take a look at some of the most innovative gas-detection offerings available on the market
Canaries were used in mines from the late 1800s to detect gases, such as carbon monoxide. In large quantities, “the gas is deadly to humans and canaries alike, but canaries are much more sensitive to small amounts of the gas, and so will react more quickly than humans,” writes Lewis Pollard, assistant curator of the Science and Industry Museum in Manchester.
In a blog post, “Exploring our Collection: The Canary Resuscitator”, he tells the story of Scottish scientist John Haldane, who was asked to help determine the cause of an explosion at Tylorstown Colliery in 1896. “He concluded the explosion was caused by a build-up of carbon monoxide and set out to find a way of detecting the odourless gas before it could harm humans.”
The result was a canary-resuscitator cage. This apparatus had a circular door, which would be kept open, with a grill to prevent the captive canary from escaping. “Once the canary showed signs of carbon monoxide poisoning the door would be closed and a valve opened, allowing oxygen from the tank above to be released and revive the canary. The miners would then be expected to evacuate the danger area,” writes Pollard.
From canaries to high-tech devices
Gas-detection equipment has come a long way since then, but the industry is still facing a number of challenges as users require reliable detection, long-term stability of sensors and, most importantly, a system ensuring less risk vulnerability.
Luckily a number of companies have stepped up to the challenge. Dräger, an international manufacturer and supplier of safety and medical equipment, has had a South African division since the early 1990s (and was represented by a local distributor before then). “Dräger supports the digitalisation of safety technology at a customer’s site with innovative products and services,” says Sagaran Chetty, marketing manager of its gas detection division. “We also optimise system availability, for example, through flexible, condition-based and predictive maintenance of gas sensor heads.”
The company offers both portable as well as flame and gas detection products. “Portable detection offers personal air monitoring, area monitoring, and confined-space entry solutions,” Chetty explains.
“Flame and gas detection offer various detection-principle transmitter sensors to system controllers; namely catalytic bead, infrared and electrochemical sensors. This technology ranges across a broad portfolio, depending on your specific requirements. We offer rental options for gas detection as well as post-sales service and maintenance for all our instruments.”
For portable gas detection Dräger tubes are available in more than 250 variants for spot measurements. “Our Pac series is for personal gas monitoring,” notes Chetty. “We have multi-gas detectors available that can measure up to seven various gases at once in our X-am range. These units can be used as confined-space entry devices as well – when paired with our X-am pump devices.”
He adds that the X-am 5000 and X-am 5600 devices can be used as area monitoring devices when paired with Dräger’s X-zone devices. “We also have a device for calibration and bump testing in our X-dock that has the facility to run reports and record test information.
“Our fixed gas detection solutions can vary from a single device station to our completely customisable solution that has the ability to monitor in excess of 1 500 inputs in the Dräger REGARD 7000 controllers.”
He explains that the company’s transmitters work on various sensor technologies across the Dräger Polytron series. “Based on system requirements these solutions are built and specified in conjunction with the different transmitters available and the various specifications and standards these devices meet.”
For flame detection the company offers its Flame 3000 and 5000 models. “We have wireless solutions available as well for hydrocarbon detection in our Dräger GS01 model and we will be introducing wireless electrochemical sensor detection,” he says. “Another addition will be our Acoustic detector that measures gas leaks based on sound level.”
He notes that the path to a smart plant is via the digitalisation of all industrial sectors, from production to logistics. “The focus here is on networking systems, sensors and controls as well as the use of artificial intelligence,” he explains. “This also has an impact on safety technology: The digital networking of measurement technology and the linking of data creates completely new possibilities.
“The digital networking of production facilities in industry is a global trend. Safety technology is also benefiting from digitalisation and the Industrial Internet of Things (IIoT). Networked gas detection technology, for example, increases the level of occupational safety through faster, more efficient and more robust processes.”
A bird’s eye view
Gas and flame equipment specialist Trigas Agencies is offering a stellar example of networked gas-detection units. “We have in Blackline Safety innovative portables that connect via the cellular as well as the GPS network to a cloud portal which, on a platform, allows the control-room operator not only to monitor an employee’s whereabouts, but also see the unit’s gas readings,” says Alan Lewis, managing member of Trigas.
“Should any units go above the limits as prescribed by the Occupational Safety and Health Act, the operator and control personnel will receive an alarm. Emergency personnel can then be despatched.”
The unit is also equipped with an emergency pull-alarm latch, a fall alarm, a no-movement alarm and a check-in function. “Should an alarm of any sort be detected the control room can call the user on their gas detector to determine if the individual is okay,” he points out.
“The control can also text the device to communicate with the person. The user can also text back. There is also an option to enable push-to-talk, which turns the connected safety gas detector into a communication device.”
With 99 available channels, different plants within the facility can be autonomous. “However, master units can be set to text and/or talk to all – for example, in the event of a fire,” he says. “This will enable the fire chief to direct the traffic to safe muster points. There are units available in a satellite configuration as well for areas where there is no cellular coverage.”
Apart from the popular portable solutions from Blackline Safety, Trigas offers fixed gas detectors and gas detection by laser. The fixed offering is made by Uniphos and Laser is done by Boreal.
Blackline Safety has also launched a new flammable sensor, called the MPS – which stands for Molecular Property Spectrometer.
“This sensor cannot be poisoned by silicon deposits, detects all flammables including hydrogen, has a low power consumption, can be calibrated with any standard test gas and can accurately measure other gasses,” says Lewis.
“It has a high and an extremely low temperature operational range. And, as we have a cloud-based portal, the gas detected can be seen in the Blackline analytics and a report produced of what flammable gases were seen and in which area.”
The cloud-based portal will show gases in different colours – say, methane in red, propane at another point in blue and hydrogen at another in green. “It will also show 11 other common gases on a Google maps format over a plant layout,” he says. “A second innovation from Blackline is the G7 EXO, which is an area monitor that can be added to any portal configuration. This unit has a 100-hour battery life, and can be charged by a solar panel.”
Fly into the future
Chetty adds this safety connectivity will continue to rise. “In the future, information will be available in real time from a variety of sources – such as single-gas detection devices, for personal protective equipment, devices for area monitoring, and stationary gas measuring sensors permanently installed in the plant.”
Lewis agrees: “The future is bright with advanced products that are safety orientated for the protection of all. Innovation has come a long way from a canary in a cage.”