Table 1.

Root mean square error in ppm between the CEAS LGR and each K30 NDIR sensor’s 1 min averaged data for the original dataset before correction, at each step of the successive regression correction (correcting for (1) zero/span, (2) atmospheric pressure, (3) temperature and (4) water vapor mixing ratio) and after the multivariate regression correction. Each value shown is for a regression calculated using data from the entire evaluation period.

	Original	Zero/span	Pressure	Temp.	q (final)	Multivariate
K30–1	6.9	3.3	2.7	2.7	2.1	1.8
K30–2	5.4	3.5	2.2	2.2	1.9	1.7
K30–3	10.9	6.0	5.0	4.9	4.5	4.3
K30–4	20.8	3.7	2.5	2.4	1.9	1.7
K30–5	8.3	3.7	2.6	2.6	2.2	2.0
K30–6	15.2	4.9	3.6	3.5	2.7	2.2