This table was reviewed on 5 November 2020 and refers to the ISO 17034 scope (Issue No. 001) and ISO 17025 scope (Issue No. 052) for EffecTech in the UK only.

For the most up-to-date information, as well as the scopes for EffecTech Gases PvT Ltd (India) and EffecTech Qatar, see EffecTech’s ISO 17025 scope.

  Primary Reference Gas Mixtures (PRGM)   Certified Reference Materials (CRM)
        ISO 17025 calibration and measurement capability (CMC)*
  amount fraction (% mol/mol) amount fraction (% mol/mol) amount fraction (% mol/mol unless stated as ppm) amount fraction (% mol/mol unless stated as ppm)
nitrogen 0.02 to 25 0.12 % relative + 0.00034 0.1 to 22 0.25 % relative +0.0005
carbon dioxide 0.05 to 25 0.10 % relative + 0.00006 0.05 to 15 0.18 % relative + 0.0001
methane 34 to 100 0.055 – 0.05 % relative 34 to 100 0.11-0.10 % relative
ethane 0.1 to 35 0.12 % relative + 0.00026 0.1 to 35 0.25 % relative
propane 0.05 to 20 0.15 % relative + 0.00002 0.05 to 15 0.3 % relative
iso-butane 0.01 to 2 0.15 % relative + 0.00011 0.01 to 0.15 0.00045
0.15 to 2 0.3 % relative
n-butane 0.01 to 2 0.15 % relative + 0.00011 0.01 to 0.15 0.00045
0.15 to 2 0.3 % relative
neo-pentane 0.001 to 0.5 0.35 % relative + 0.00005 0.002 to 0.35 0.7 % relative + 0.0001
iso-pentane 0.002 to 0.6 0.25 % relative + 0.00005 0.005 to 0.35 0.5 % relative + 0.0001
n-pentane 0.002 to 0.6 0.25 % relative + 0.00005 0.005 to 0.35 0.5 % relative + 0.0001
n-hexane 0.001 to 0.5 0.50 % relative + 0.00005 0.001 to 0.35 1.0 % relative + 0.0001
2-methylpentane 0.001 to 0.35 0.65 % relative + 0.00003 0.001 to 0.35 1.3 % relative + 0.00005
3-methylpentane 0.001 to 0.35 0.65 % relative + 0.00003 0.001 to 0.35 1.3 % relative + 0.00005
2,2-dimethylbutane 0.001 to 0.35 0.65 % relative + 0.00003 0.001 to 0.35 1.3 % relative + 0.00005
benzene 0.001 to 0.2 0.65 % relative + 0.00003 0.001 to 0.2 1.3 % relative + 0.00005
cyclohexane 0.001 to 0.2 0.65 % relative + 0.00003 0.001 to 0.2 1.3 % relative + 0.00005
n-heptane 0.001 to 0.2 0.65 % relative + 0.00003 0.001 to 0.2 1.3 % relative + 0.00005
toluene 0.001 to 0.1 0.65 % relative + 0.00003 0.001 to 0.1 1.3 % relative + 0.00005
methylcyclohexane 0.001 to 0.1 0.65 % relative + 0.00003 0.001 to 0.1 1.3 % relative + 0.00005
n-octane 0.0005 to 0.05 0.65 % relative + 0.00003 0.0005 to 0.05 1.3 % relative + 0.00005
n-nonane 0.0001 to 0.02 0.65 % relative + 0.00003 0.0005 to 0.02 1.3 % relative + 0.00005
n-decane 0.0001 to 0.005 0.65 % relative + 0.00003 0.0005 to 0.005 1.3 % relative + 0.00005
C6+ N/A 0.001 to 0.35 1.0 % relative + 0.0001
helium 0.005 to 0.2 0.85 % relative + 0.00022 0.005 to 0.2 1.7 % relative + 0.0004
hydrogen 0.005 to 0.2 0.80 % relative + 0.0002 0.005 to 0.2 1.7 % relative + 0.0002
oxygen N/A 10 ppm to 100 ppm 1.6 % relative + 0.1 ppm
100ppm to 1000 ppm 0.9 % relative + 0.5 ppm
0.1 to 1.0 0.7 % relative + 1.0 ppm
1.0 to 22.5** 0.18 % relative + 30 ppm
* The calibration and measurement capability is based on a standard uncertainty multiplied by a coverage factor k=2, providing a level of confidence of approximately 95%. The uncertainty evaluation has been carried out in accordance with UKAS requirements
** The upper limit for oxygen may be limited due to restrictions in place required for the safe manufacture of such mixtures.