Division Averaging periods and reference conditions for air emissions

United Kingdom

Unless stated otherwise, emission levels associated with the best available techniques (BAT-AELs) for air emissions given in these BAT conclusions apply under the reference conditions shown in Table 1. All values for concentrations in waste gases refer to standard conditions: dry gas, temperature 273,15 K, pressure 101,3 kPa.

For discontinuous measurements	BAT-AELs refer to the average value of three spot samples of at least 30 minutes each; for regenerative furnaces the measuring period should cover a minimum of two firing reversals of the regenerator chambers
For continuous measurements	BAT-AELs refer to daily average values

Table 1

Reference conditions for BAT-AELs concerning air emissions

Activities		Unit	Reference conditions
Melting activities	Conventional melting furnace in continuous melters	mg/Nm³	8 % oxygen by volume
	Conventional melting furnace in discontinuous melters	mg/Nm³	13 % oxygen by volume
	Oxy-fuel-fired furnaces	kg/tonne melted glass	The expression of emission levels measured as mg/Nm³ to a reference oxygen concentration is not applicable
	Electric furnaces	mg/Nm³ or kg/tonne melted glass	The expression of emission levels measured as mg/Nm³ to a reference oxygen concentration is not applicable
	Frit melting furnaces	mg/Nm³ or kg/tonne melted frit	Concentrations refer to 15 % oxygen by volume. When air-gas firing is used, BAT AELs expressed as emission concentration (mg/Nm³) apply. When only oxy-fuel firing is employed, BAT AELs expressed as specific mass emissions (kg/tonne melted frit) apply. When oxygen-enriched air-fuel firing is used, BAT AELs expressed as either emission concentration (mg/Nm³) or as specific mass emissions (kg/tonne melted frit) apply
	All type of furnaces	kg/tonne melted glass	The specific mass emissions refer to 1 tonne of melted glass
Non-melting activities, including downstream processes	All processes	mg/Nm³	No correction for oxygen
Non-melting activities, including downstream processes	All processes	kg/tonne glass	The specific mass emissions refer to 1 tonne of produced glass