Sch 1J para 3 Maximum permissible errors (MPEs)
For each of the fractions measured, the maximum error value permitted under rated operating conditions according to paragraph 1.1 of Schedule 1A is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. ± 0.03 % vol ± 5 % ± 0.06 % vol ± 5 %