Guidance

Operating a mobile boiler as a medium combustion plant (MCP): RPS 354

Updated 8 July 2025

Applies to England

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This publication is available at https://www.gov.uk/government/publications/operating-a-mobile-boiler-as-a-medium-combustion-plant-mcp-rps-354/operating-a-mobile-boiler-as-a-medium-combustion-plant-mcp-rps-354

This regulatory position statement (RPS) does not change your legal requirement to have an environmental permit when you operate a mobile boiler that is a MCP.

However, the Environment Agency will not normally take enforcement action if you do not comply with this legal requirement provided that:

  • your activity meets the description set out in this RPS

  • you comply with the conditions set out in this RPS

  • your activity does not cause (and is not likely to cause) pollution of the environment or harm to human health

1. Activity this RPS applies to

This RPS applies to temporarily located steam and hot water boiler plant that are mobile MCP.   

2. Conditions you must comply with

You must:

  • maintain and operate the mobile boilers in accordance with the manufacturer’s instructions

  • keep records for 2 years from the date of the last use of the RPS to show that you have complied with this RPS and make these records available to the Environment Agency on request

Where mobile boilers are used at regulated facilities, you must also notify the Environment Agency by contacting your local regulatory officer and including the:

  • capacity (MWth) of the boiler plant
  • fuel used
  • duration of plant on site

You must not:

  • use mobile boilers at the same site for more than 12 months

  • use mobile boilers to increase the operational thermal capacity where a regulated facility is undertaken

3. Things to note

Regulated facility includes an installation, waste operation, and MCP.

The Environment Agency proposes to consult on a permitting solution for mobile boilers whilst this RPS is in place.

4. When you must check back

The Environment Agency will review this RPS by 7 July 2027.   

The Environment Agency can withdraw or amend this regulatory position before the review date if they consider it necessary. This includes where the activity that this RPS relates to has not changed.

You will need to check back from time to time, including at and before the review date, to see if this RPS still applies.

You can subscribe to email updates about this RPS. These will tell you if the RPS has changed and when it has been withdrawn.

This RPS remains in force until it is removed from GOV.UK or is otherwise identified as having been withdrawn.

5. If you cannot comply with this RPS

If you operate under this RPS but can no longer comply with it, you must stop the activity to which this RPS relates and must tell the Environment Agency immediately by emailing enquiries@environment-agency.gov.uk with RPS 354 in the subject.

6. Contact the Environment Agency

If you have any questions about this RPS email enquiries@environment-agency.gov.uk with RPS 354 in the subject.

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