# Commission Implementing Decision of 9 October 2014 establishing best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council on industrial emissions, for the refining of mineral oil and gas (notified under document C(2014) 7155) (Text with EEA relevance) (2014/738/EU), Division BAT 4: BAT is to monitor emissions to air by using the monitoring techniques with at least the minimum frequency given below and in accordance with EN standards. If EN standards are not available, BAT is to use ISO, national or other international standards that ensure the provision of data of an equivalent scientific quality.

Extent: E+W+S+N.I.

Continuous measurement of SO2 emissions may be replaced by calculations based on measurements of the sulphur content of the fuel or the feed; where it can be demonstrated that this leads to an equivalent level of accuracy.
Regarding SOX, only SO2 is continuously measured, while SO3 is only periodically measured (e.g. during calibration of the SO2 monitoring system).
Refers to the total rated thermal input of all combustion units connected to the stack where emissions occur.
Or indirect monitoring of SOX.
Monitoring frequencies may be adapted if, after a period of one year, the data series clearly demonstrate a sufficient stability.
SO2 emissions measurements from SRU may be replaced by a continuous material balance or other relevant process parameter monitoring, provided appropriate measurements of SRU efficiency are based on periodic (e.g. once every 2 years) plant performance tests.
Antimony (Sb) is monitored only in catalytic cracking units when Sb injection is used in the process (e.g. for metals passivation).
With the exception of combustion units firing only gaseous fuels.
Description
Unit
Minimum frequency
Monitoring technique
(i)
SOX, NOX, and dust emissions
Catalytic cracking
Continuous
Direct measurement
Combustion units
≥ 100 MW
and calcining units
Continuous
Direct measurement
Combustion units
of 50 to 100 MW
Continuous
Direct measurement or indirect monitoring
Combustion units
< 50 MW
Once a year and after significant fuel changes
Direct measurement or indirect monitoring
Sulphur recovery units (SRU)
Continuous for SO2 only
Direct measurement or indirect monitoring
(ii)
NH3 emissions
All units equipped with SCR or SNCR
Continuous
Direct measurement
(iii)
CO emissions
Catalytic cracking and combustion units
≥ 100 MW
Continuous
Direct measurement
Other combustion units
Once every 6 months
Direct measurement
(iv)
Metals emissions: Nickel (Ni), Antimony (Sb), Vanadium (V)
Catalytic cracking
Once every 6 months and after significant changes to the unit
Direct measurement or analysis based on metals content in the catalyst fines and in the fuel
Combustion units
(v)
Polychlorinated dibenzodioxins/furans (PCDD/F) emissions
Catalytic reformer
Once a year or once a regeneration, whichever is longer
Direct measurement

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Source: https://www.legislation.gov.uk/eudn/2014/738/annex/division/3/division/1.1/division/1.1.4/division/BAT (the official version)
Page: https://openlegislation.uk/eu-decision-2014-738/annex/division-3/division-1.1/division-1.1.4/division-BAT
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.