GAW Report No. 264
Report of the Sixth Methane Reference Gas Inter-comparison Experiment for Asia from 2018 to 2019
Teruo Kawasaki, Atsuya Kinoshita, Yousuke Sawa, Shuangxi Fang, Haeyoung Lee, Yogesh K. Tiwari
The WCC-JMA organized six rounds of the CH4 reference gas inter-comparison experiments from 2001 to 2019 to quantify differences among CH4 standard scales implemented at each participating laboratory as well as to monitor the long-term stability of standard gases in Asia and the South-West Pacific. In the 6th round robin inter-comparison for Asia, two reference gas cylinders were circulated in turn to JMA, CMA, KMA/NIMS, IITM, and JMA from January 2018 to September 2019. The inter-comparison results confirmed that the differences between each laboratory and WCC-JMA were within the GAW network extended compatibility goal of ±5 ppb.