The latest range of Riken gas detectors is available in Australia from Control Products.
While people involved within the fumigation industry may be familiar with the likes of the Riken FI-21 and the Riken GH-202, when it comes to gas detection, few would be aware of the background of the company that manufacture these instruments.
Riken, a Japanese company, has been in the gas detection business since 1939 and was amongst the first inventors of the modern gas detector. Prior to this, the industry was reliant on the use of a live canary in a cage! While the canaries were more susceptible to low oxygen or methane gas, it was actually less sensitive to other gases and therefore gave humans a false sense of security. The best they could do to overcome this dilemma was to put two canaries in the cage, not an ideal fix for the problem at hand.
In 1927 Dr Ziro Tsuji, from the Institute of Physical & Chemical Research in Japan, was developing the first prototype of the interferometer. This came about because of a need to prevent explosions on oil tankers and in coal mines. The interferometer uses the principle of light diffraction in air to indicate the presence of methane or gasoline vapours. The light diffraction creates visible fringe lines that shift to indicate gas concentration. In 1935 some 40 units were sold to a coal mine in Hokkaido and it wasn’t until 3 years later that Dr Tsuji created a company called Riken and began full production.
In 1952 the Model 18 instrument was developed using the same interferometer technology. It used a manually operated sample pump to draw in the gas for evaluation. The operator then needed to look into the eyepiece which, with the presence of a specific gas, caused the light to refract thus giving an accurate gas reading.
Although there were some incremental improvements, there was no significant development for nearly 50 years.
Fast forward to 2001 and the development of the Riken FI-21, which featured an electronic sample pump, digital display, data logging and the ability to detect each of the common fumigation gases (phosphine, methyl bromide and sulfuryl fluoride) all in the one instrument. This was seen as a great advancement within the industry and one that was well received.
In 2015, we saw the arrival of the Riken FI-8000 (main picture, above) an improvement on the FI-21. The FI-8000 is a more compact instrument and is almost 1kg lighter that its older brother (FI-21). The larger display allows easy viewing of all readings as well as the push buttons being fully sealed to prevent dirt and grime getting underneath them.
Previously Riken did not have an instrument suitable for clearance work, but with the introduction of the GX-6000 this is now no longer the case. The GX-6000 provides detection of up to six gases in the one instrument including phosphine and methyl bromide down to ppb (parts per billion) levels.
The GX-6000 is a hand held instrument that has a photo-ionisation detector (PID) sensor as well as a separate electrochemical toxic sensor for phosphine. Weighing less than 500 grams the GX-6000 is the lightest and the most versatile six-gas detector in the market today.
The Riken range of instruments is available in Australia through Control Equipment.