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Is your plant covered?
- 1–50 MW rated thermal input: boilers, engines and gas turbines with a rated thermal input of at least 1 MW and at most 50 MW. It is the fuel input that counts, not the heat output (sections 3 and 4).
- 2018 plant or new: if the plant was put into operation by 19 December 2018 it is a 2018 plant (the ordinance's term for an existing plant), otherwise it is new. That decides which limit values apply and from which date (section 5).
- New plants are added together if each is at least 1 MW and the flue gases are discharged, or technically and economically could be discharged, through a common stack. 2018 plants are counted one by one (section 4).
- Waste and large plants: if you burn waste, such as painted or impregnated recovered wood, the rules on waste incineration apply. If the plant reaches 50 MW (alone or added together with others of at least 15 MW), the rules on large combustion plants apply (section 15).
- Excluded are, among others, dryers and furnaces where the flue gases are used directly in the process, post-combustion that cleans process gases, recovery boilers in the pulp industry, crematoria, engines in vehicles, ships and aircraft, and mobile machinery (section 15).
- The permit applies at the same time: the ordinance applies on top of the conditions in permits and injunctions. You must comply with both, and the strictest requirement governs (section 17).
What must be measured, and how often?
According to section 43 of the ordinance (SFS 2018:471), you must measure the concentration in the flue gas of those parameters – nitrogen oxides (NOx), sulphur dioxide (SO2) and dust – that have a limit value for your plant, and always carbon monoxide (CO) as well. Limit value (begränsningsvärde) is the ordinance's word for emission limit value. The measurement is periodic: it is made on one occasion when the plant runs stably at a representative and even load (section 46).
| Plant | What is measured | How often |
|---|---|---|
| 20 MW or less | NOx, dust and SO2 where a limit value applies, and CO | At least once every three years |
| More than 20 MW | The same parameters | At least once every year |
| At most 500 operating hours per year, 20 MW or less | CO, and dust if you burn solid fuels | The measurement may wait until the plant has run 1,500 operating hours since the last one, but never longer than five years |
| At most 500 operating hours per year, more than 20 MW | CO, and dust if you burn solid fuels | The measurement may wait until the plant has run 500 operating hours since the last one, but never longer than five years |
| The first measurement | The parameters that apply to the plant | Within four months of registration, or of commissioning if that comes later (section 45) |
| Continuous measurement decided by an authority | The automated measuring system | Checked by parallel measurements against reference methods at least once a year (section 48) |
Operating hours are counted without start-up and shut-down periods (section 6). The 500 operating hours per year is a rolling average over five years for 2018 plants and over three years for new ones (sections 35 and 37).
Parameters and methods
Which parameters you must measure depends on the fuel. The methods must give reliable, representative and comparable results, and methods according to harmonised EN standards are considered to meet that requirement (section 50).
| Parameter | Measured when you burn | Reference method |
|---|---|---|
| NOx | All fuels | EN 14792 |
| Dust | Solid fuels, and liquid fuels other than gas oil | EN 13284-1 |
| SO2 | All fuels except wood fuel (solid biomass from forestry), gas oil and natural gas | EN 14791 |
| CO | All fuels, also when the plant is exempt from the limit values. CO has no limit value of its own | EN 15058 |
| Oxygen, moisture and gas flow | At every measurement, for the conversion to dry gas at the reference oxygen content and for the dust sampling | EN 14789, EN 14790 and EN ISO 16911-1 |
The supervisory authority may grant an exemption from the measurement of SO2. The emission must then be checked in another way (section 47).
Which limit values apply? Older boilers (2018 plants)
The limit values are in annexes 1–20 to the ordinance. They are given in mg/Nm3 dry gas, at 6 % O2 for solid fuels and 3 % O2 for liquid and gaseous fuels in boilers (section 38), and are compared with the result of the periodic measurement. A dash means that there is no limit value, and the parameter then does not need to be measured. The table applies to boilers and other plants that are not engines or gas turbines and that were put into operation by 19 December 2018 (section 25 and annexes 1–3). The values have applied since 1 January 2025 above 5 MW and apply from 1 January 2030 for 5 MW or less. The permit can set stricter requirements, and the wording of the ordinance is what applies.
| Fuel | SO2 | NOx | Dust |
|---|---|---|---|
| Solid biomass from forestry (wood chips, bark, sawdust and wood pellets) | – | 300 | 50 (20 MW or less) 30 (more than 20 MW) |
| Straw | 300 | 300 | 50 (20 MW or less) 30 (more than 20 MW) |
| Other solid biomass | 200 | 300 | 50 (20 MW or less) 30 (more than 20 MW) |
| Other solid fuel, for example peat and coal | 400 | 300 | 50 (20 MW or less) 30 (more than 20 MW) |
| Gas oil (heating oil no. 1 and diesel) | – | 200 | – |
| Liquid biofuel | 350 | 450 | 50 (5 MW or less) 30 (more than 5 MW) |
| Other liquid fuel | 350 | 300 | 50 (5 MW or less) 30 (more than 5 MW) |
| Natural gas | – | 250 (5 MW or less) 200 (more than 5 MW) | – |
| Biogas | 200 (5 MW or less) 170 (more than 5 MW) | 250 | – |
| Other gaseous fuel | 200 (5 MW or less) 35 (more than 5 MW) | 250 | – |
Biogas in plants of 5 MW or less counts as other gaseous fuel. Coke oven gas and blast furnace gas have their own values in the annexes.
Limit values for new boilers
For boilers and other plants that are not engines or gas turbines and that were put into operation after 19 December 2018, the values in annexes 12–14 apply from day one (section 29). The unit and the oxygen content are the same as in the table above. If several new plants are added together, the combined thermal input decides the size class.
| Fuel | SO2 | NOx | Dust |
|---|---|---|---|
| Solid biomass from forestry (wood chips, bark, sawdust and wood pellets) | – | 300 | 50 (5 MW or less) 30 (more than 5 to 20 MW) 20 (more than 20 MW) |
| Other solid biomass, including straw | 200 | 300 | 50 (5 MW or less) 30 (more than 5 to 20 MW) 20 (more than 20 MW) |
| Other solid fuel, for example peat and coal | 400 | 300 | 50 (5 MW or less) 30 (more than 5 to 20 MW) 20 (more than 20 MW) |
| Gas oil (heating oil no. 1 and diesel) | – | 200 | – |
| Other liquid fuel, including liquid biofuel | 350 | 300 | 50 (5 MW or less) 20 (more than 5 MW) |
| Natural gas | – | 100 | – |
| Biogas | 100 | 200 | – |
| Other gaseous fuel | 35 | 200 | – |
Coke oven gas and blast furnace gas have their own values in the annexes.
Limit values for engines and gas turbines
Engines and gas turbines have their own values, all at 15 % O2 (sections 26–28 and 30–32, annexes 4–11 and 15–20). NOx is given in mg/Nm3. For 2018 plants the values have applied since 1 January 2025 above 5 MW and apply from 1 January 2030 for 5 MW or less. For gas turbines the limit values apply when the load is above 70 %.
| Plant and fuel | NOx, 2018 plant | NOx, new plant |
|---|---|---|
| Engine – gas oil | 250 (5 MW or less) 190 (more than 5 MW) | 190 |
| Engine – other liquid fuel | 250 (5 MW or less) 225 (more than 5 to 20 MW) 190 (more than 20 MW) | 190 225 at 1,200 rpm or less and 20 MW or less |
| Engine – natural gas | 190 | 95 |
| Engine – biogas and other gases | 190 | 190 |
| Dual-fuel engine – gas oil | 250 (5 MW or less) 190 (more than 5 MW) | 225 |
| Dual-fuel engine – other liquid fuel | 250 (5 MW or less) 225 (more than 5 to 20 MW) 190 (more than 20 MW) | 225 |
| Dual-fuel engine – natural gas, biogas and other gases | 380 | 190 |
| Gas turbine – gas oil and other liquid fuel | 200 | 75 |
| Gas turbine – natural gas | 150 | 50 |
| Gas turbine – biogas and other gases | 200 | 75 |
Engine here means an engine other than a dual-fuel engine. A dual-fuel engine runs on both liquid fuel and gas (section 12). SO2 in mg/Nm3: 120 for other liquid fuel, 60 for biogas (40 in new plants) and 15 for other gases except natural gas. Dust has a limit value only for other liquid fuel: in 2018 plants 20 mg/Nm3 up to and including 20 MW and 10 above 20 MW, in new plants 20 up to and including 5 MW and 10 above 5 MW. Coke oven gas and blast furnace gas have their own SO2 values in the annexes.
Key dates
The dates come from the ordinance's transitional provisions and section 45. A 2018 plant of 20 MW or less that measured for the first time in 2024 must measure again in 2027.
| Date | What applies |
|---|---|
| 19 December 2018 | Last day of commissioning as a 2018 plant. Plants put into operation later are new. |
| 20 December 2018 | The limit values for new plants came into effect. A new plant may not operate without being registered. |
| 1 January 2024 | 2018 plants above 5 MW may no longer operate without being registered. |
| 1 January 2025 | The limit values apply to 2018 plants above 5 MW. |
| 1 January 2029 | 2018 plants of 5 MW or less must be registered. |
| 31 December 2029 | Last day of the higher dust value for sawmills and other wood product manufacturing. |
| 1 January 2030 | The limit values also apply to 2018 plants of 5 MW or less. |
| Within four months | The first measurement, counted from registration or commissioning, whichever comes last. |
| At least six years | How long measurement results and other records must be kept. |
How to meet the requirements
Find out what applies
Start from three facts: the rated thermal input, when the plant was put into operation and which fuels you burn. They give you the limit values, parameters and measurement intervals in the tables above.
Register the plant
Submit the information in section 18 to the supervisory authority, which is usually the municipal environmental committee and otherwise the County Administrative Board: among other things the thermal input, type of plant, fuels, expected operating hours and flue gas cleaning equipment. The plant may not operate without being registered (section 21). If you later plan a change that affects the limit values, for example a new fuel, you must inform the authority without undue delay (section 19).
Check the measurement site
The measurement needs sampling ports on a straight run of duct, a safe working platform and electricity, according to EN 15259. If there are no sampling ports, we help you decide where they should go before they are cut.
Book the measurement in time
The first measurement must be done within four months of registration or commissioning. It is made when the plant runs stably at a representative and even load, and with the fuel that gives the highest emissions if you burn several.
Measurement and report
In one visit we normally measure dust, NOx and CO, SO2 where the fuel requires it, and oxygen, moisture and gas flow. You receive an accredited report with the measured values converted to mg/Nm3 dry gas at the right reference oxygen content, with the measurement uncertainty.
Keep the records and follow up
Keep the report and the registration certificate for at least six years, together with records of fuels, the performance of the flue gas cleaning equipment and any exceedances (section 56). The supervisory authority can ask for the records, and some municipalities want the measurement results after every measurement.
Exemptions and relief
Plants that run at most 500 operating hours per year are exempt from the limit values (sections 35 and 37). If you burn solid fuels, a dust value still applies: 200 mg/Nm3 for 2018 plants and 100 mg/Nm3 for new ones. The plant must still be registered, measure CO and document its operating hours. If exceptional cold threatens to cause an emergency, a 2018 plant may run up to 1,000 hours, if you notify the supervisory authority as soon as possible (section 36).
Sawmills and other wood product manufacturers that burn solid biomass in a 2018 plant have a higher dust value up to and including 2029: 150 mg/Nm3 above 5 to 20 MW and 50 mg/Nm3 above 20 MW, except where the environmental quality standards for particulate matter are exceeded. The Swedish ordinance has no special exemption for district heating. If the fuel supply is interrupted, the supervisory authority can grant a time-limited exemption (sections 39 and 40).
How is the measured value compared with the limit value?
The measured value is converted to mg/Nm3 dry gas at 0 °C and 101.3 kPa and to the oxygen content that applies to the fuel (sections 13 and 38). At periodic measurement the limit value is complied with if the measurement results show that it has not been exceeded (section 51). The ordinance specifies no deduction for measurement uncertainty at periodic measurement. Such a deduction exists only for continuous measurement, where validated averages are compared with the limit value (sections 52 and 53). The measurement uncertainty is stated in the report.
Start-up and shut-down periods are not counted (section 54). If you burn several fuels, the measurement must be made with the fuel or fuel mix that you judge gives the highest emissions (section 49), and the limit value is weighted by how much thermal input each fuel contributes (sections 33 and 34).
If a limit value is exceeded
If the measurement shows that a limit value is not complied with, you must inform the supervisory authority as soon as possible and at the same time describe what you have done or intend to do to comply with the value (section 55). The supervisory authority can order you to take action, if necessary backed by a conditional fine (chapter 26, sections 9 and 14 of the Swedish Environmental Code). Breaching the ordinance's limit values or measurement requirements can also be a criminal offence, and the authority must report suspected offences (chapter 26, section 2 and chapter 29, section 8 of the Environmental Code). Once the fault has been corrected, a new measurement shows whether the value is complied with.
What does the measurement cost?
The price depends on how many boilers and stacks are to be measured, which parameters the fuel requires, the conditions at the measurement site and the travel distance. A gas boiler where only NOx and CO are measured is quicker than a solid-fuel boiler where dust must be sampled as well. If we measure several boilers on the same visit, or coordinate with a comparison measurement for the Swedish NOx charge, the price per boiler is lower. Request a quote – we reply within two working days. Approximate prices for the most common measurements are in the price guide.
Frequently asked questions about medium combustion plants
How often must a medium combustion plant be measured?
At least once every three years if the rated thermal input is 20 MW or less, and at least once every year if it is more than 20 MW (section 43). The first measurement must be made within four months of registration or commissioning.
What must a 5 MW wood-chip boiler measure?
NOx, dust and carbon monoxide (CO), at least every three years. Wood fuel has no limit value for SO2, so SO2 does not need to be measured. The limit values are 300 mg/Nm3 for NOx and 50 mg/Nm3 for dust, at 6 % O2. For a boiler put into operation by 19 December 2018 they apply from 1 January 2030.
Who may do the measurement?
The ordinance does not say who may measure and does not require accreditation. The requirement concerns the methods: they must give reliable, representative and comparable results, and methods according to EN standards are considered to do so (section 50). EN 15259 presupposes a competent testing laboratory and refers to ISO/IEC 17025. METLAB is accredited by Swedac for the measurements.
Do emergency generators and standby boilers have to be measured?
Yes, if they have a rated thermal input of at least 1 MW. With at most 500 operating hours per year they are exempt from the ordinary limit values, but they must be registered and measure carbon monoxide (CO): the first time within four months of registration, then at the latest after 1,500 operating hours (500 above 20 MW) and at least every five years.
What applies to an older 1–5 MW boiler until 2030?
A boiler put into operation by 19 December 2018 must be registered by 1 January 2029 and comply with the limit values from 1 January 2030. The supervisory authority has one month to register it, so submit the information in good time. The first measurement must be made within four months of registration. Then you will see whether the boiler meets the values or needs work.
Is the comparison measurement enough when we pay the Swedish NOx charge?
Not on its own. The comparison measurement under NFS 2016:13 checks your own NOx measuring equipment. The ordinance (SFS 2018:471) also requires measurement of CO and, depending on the fuel, of dust and SO2. The measurements can be made on the same visit.
Is registration enough, or is a notification or a permit also required?
Registration does not replace the permit or notification procedure under the Swedish Ordinance on Environmental Permits and Notifications (SFS 2013:251). Plants with a total rated thermal input of more than 20 MW require a permit, and smaller plants often require a notification. Where the threshold lies depends on the fuel (chapter 21, sections 10–12). Ask the supervisory authority if you are unsure.
Do the MCP Directive's limit values apply in Sweden?
In Sweden the values in the ordinance (SFS 2018:471), which implements Directive (EU) 2015/2193, apply. On several points they are stricter than the directive's minimum requirements. For 2018 plants burning solid fuels, for example, the NOx value is 300 mg/Nm3, against 650 in the directive.