Updated: January, 2008
Seven standards now comprise the GML CCl4 scale. Four standards prepared in 1996 were
removed from the scale due to inconsistent performance.
The 2008 scale is 0.4% lower than the 1996 scale based on ECD results.
Standard	Prepared	Assigned	Difference
	(ppt)	(ppt)	(ppt)
SX-3519	49.8	49.02	-0.76
SX-3518	25.4	26.18	0.78
SX-3522	41.5	41.21	-0.29
SX-3506	94.3	94.91	0.64
SX-3505	47.3	46.97	-0.30
ALM-33800	127.71	127.93	0.22
ALM-65990	153.09	152.80	-0.29
		std dev	0.57