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Where do the emissions come from?
- Process vents. Reactors, distillation, centrifuges and dryers vent solvents and reaction products: TOC, individual VOCs such as toluene and dichloromethane, sometimes HCl. Batch processes give peaks that the measurement must capture.
- Solvent use and storage. Extraction, coating, cleaning and tank farms give channelled and diffuse emissions. The diffuse ones are calculated in a solvent mass balance and followed up with leak detection and repair (LDAR).
- Oxidation and scrubbers. Thermal or catalytic oxidation removes VOCs but forms NOx and CO; chlorine-containing waste gases can give HCl and dioxins. Scrubbers emit residues of HCl, NH3 or SO2.
- Boilers and process furnaces. Steam boilers are outside the BAT conclusions and belong under the Swedish Ordinance on Medium Combustion Plants (SFS 2018:471) or the rules for large combustion plants. Process furnaces from 1 MW are covered by the BAT conclusions, with 3 % O2 as the reference.
Which rules apply?
| Plant | Regulation | What it means for the measurement |
|---|---|---|
| Chemical industry that is an IED activity: chemicals, pharmaceuticals, polymers (chapter 12 of the Swedish Environmental Permitting Ordinance) | The BAT conclusions for common waste gas management and treatment systems in the chemical sector, (EU) 2022/2427, through the Swedish Industrial Emissions Ordinance (SFS 2013:250) | BAT 8: continuous measurement at stacks above a mass flow (TVOC 2 kg C/h, NOx 2.5 kg/h), otherwise periodic every six months or once a year. BAT-associated emission levels (BAT-AELs) apply as limit values from 12 December 2026. |
| Solvent consumption above the ordinance's threshold, for pharmaceuticals 50 tonnes per year | The Swedish Ordinance on the Use of Organic Solvents (SFS 2013:254) | Limit values for point-source emissions (pharmaceuticals 20 mg C/Nm3) and for diffuse and total emissions as a percentage of the solvent input. Continuous measurement above 10 kg C/h, otherwise periodic with at least three readings (section 22). |
| Large volume organic chemicals above 20 kt per year, for example lower olefins and formaldehyde | The BAT conclusions (EU) 2017/2117, binding since 7 December 2021 | Their own BAT-AELs and measurement requirements. NOx and CO from thermal treatment of the waste gases still belong under the BAT conclusions for waste gas. |
| Boiler of 1–50 MW | SFS 2018:471 · the NOx charge from 25 GWh per year | Periodic measurement at least every three years up to 20 MW, every year above 20 MW. Boilers liable to the charge: comparison measurement every year. |
The permit applies on top of the ordinances and the BAT conclusions and can be stricter; the statutory text is what applies. The measurement frequency may be reduced if the emissions have been shown to be stable.
What is measured – and what is typical?
BAT-AELs from the BAT conclusions (EU) 2022/2427 unless stated otherwise: the level the EU's reference documents say well-run plants achieve. The upper value of the range applies as the limit value.
| Parameter | Why in this industry | Typical level or requirement | Method |
|---|---|---|---|
| TOC (TVOC) | The sum of solvents and other organic compounds | BAT-AEL < 1–20 mg C/Nm3, up to 30 with solvent recovery · the solvents ordinance: 20 mg C/Nm3 for pharmaceuticals | EN 12619 (FID) |
| Individual VOCs: benzene, toluene, dichloromethane, formaldehyde | CMR substances and chlorinated solvents have their own values | BAT-AEL < 0.5–1 mg/Nm3 (formaldehyde 1–5), sum of CMR 1A/1B < 1–5 · the solvents ordinance: 2 mg/Nm3 for CMR from 10 g/h | CEN/TS 13649 (adsorbent, laboratory analysis) |
| NOx | Oxidisers and process furnaces | BAT-AEL 5–130 mg/Nm3 after thermal oxidation, 5–30 after catalytic, 10–150 from other sources | EN 14792 |
| CO | Shows how complete the oxidation is | No BAT-AEL · indicative level 4–50 mg/Nm3 after thermal treatment | EN 15058 |
| HCl | Chlorinated processes, scrubbers | BAT-AEL 1–10 mg/Nm3 | EN 1911 |
| NH3 | Ammonia slip from SCR and SNCR, ammonia-containing processes | BAT-AEL < 0.5–8 mg/Nm3 after SCR/SNCR, 2–10 from other sources | EN ISO 21877 |
| Dust | Dryers, mills, powder handling | BAT-AEL < 1–5 mg/Nm3, 20 where filters cannot be used | EN 13284-1 |
mg/Nm3 dry gas at 273.15 K and 101.3 kPa, without oxygen correction except for process furnaces (3 % O2). Continuous measurement as a daily average, periodic as the average of three samples of at least 30 minutes. Several BAT-AELs do not apply at small mass flows. The concentration depends on the process and the abatement.
What the measurement year looks like
Establish what applies
Go through the permit, the monitoring programme and the emissions inventory (BAT 2). Decide which stacks lie above the mass flows in BAT 8 and whether the solvent consumption reaches the solvents ordinance's threshold; a first measurement of concentration and gas flow gives the mass flow.
Periodic measurement every six months or every year
We measure when the emissions are expected to be at their highest under normal operation: three samples of at least 30 minutes per parameter, TOC with an FID and individual VOCs on adsorbent. Stable levels entitle you to less frequent measurement.
Checks of automated measuring systems
Continuous measuring systems are quality assured according to EN 14181: QAL2 when the system is new and then at least every five years, AST every year. We carry out the parallel measurements.
Solvent mass balance and diffuse emissions
At least once a year a solvent mass balance is compiled (BAT 21) and the diffuse emissions are estimated (BAT 20). Leaks are searched for by sniffing or with an optical gas imaging camera in the LDAR programme (BAT 22).
The boiler and the environmental report
The steam boiler is measured under SFS 2018:471, boilers liable to the NOx charge with a NOx comparison measurement every year. The measurement reports are the basis for the annual environmental report by 31 March, where you report how the BAT conclusions are complied with.
12 December 2026: the BAT-AELs become binding
The BAT conclusions for waste gas were published on 12 December 2022. Under the Swedish Industrial Emissions Ordinance (SFS 2013:250), the BAT-AELs apply as limit values under normal operation four years later, from 12 December 2026, where the chemical activity is the main activity. The upper value of the range may not be exceeded, and an exceedance must be reported to the supervisory authority. Many plants today report calculated, not measured, VOC emissions in the Swedish Environmental Protection Agency's register Utsläpp i siffror. BAT 8 requires measurement at every relevant stack, and a first measurement shows whether the levels lie below the BAT-AELs and are stable enough for less frequent measurement.
What does a measurement cost in the chemical industry?
The price depends on the number of stacks and parameters, whether individual VOCs are to be analysed in a laboratory, whether automated measuring systems are to be checked with QAL2 or AST, and on the measurement sites. Batch processes can require more time on site. Several sources in the same visit lower the cost per measurement. Request a quote – we reply within two working days. Approximate prices for the most common measurements are in the price guide.
Frequently asked questions
Is our pharmaceutical plant covered by the BAT conclusions for waste gas?
Yes, if it is an IED activity: the manufacture of pharmaceuticals under chapter 12 of the Swedish Environmental Permitting Ordinance is among the activities that (EU) 2022/2427 applies to, with binding BAT-AELs from 12 December 2026.
How often must we measure TOC?
Under BAT 8 continuously at every stack with a mass flow of 2 kg C/h or more, otherwise every six months with EN 12619, less often if the levels have been shown to be stable. The solvents ordinance requires continuous measurement above 10 kg C/h.
What counts as a minor emission?
The BAT conclusions give examples of mass flows below which a BAT-AEL does not apply: TVOC below 100 g C/h without CMR substances, dust below 50 g/h, HCl below 30 g/h, NOx and SO2 below 500 g/h. The mass flow is concentration times gas flow, so a measurement with flow determination settles it.
Must the measurement be made by an accredited laboratory?
BAT 8 requires EN standards, and EN 14181 requires an accredited laboratory for QAL2 and AST. The permit or the monitoring programme often specifies accredited measurement. METLAB is accredited by Swedac for emission measurements and for QAL2 and AST.