Guidance

Operating a mandatory occurrence reporting system

How principal designers, principal contractors and principal accountable persons must set up and maintain a system to report building safety incidents and risks.

Applies to England

Who must operate a mandatory occurrence reporting system

Principal designers and principal contractors

The principal designer and principal contractor must establish and operate a mandatory occurrence reporting (MOR) system, during:

  • construction of a new higher-risk building
  • work on an existing higher-risk building, unless the work consists only of exempt work or emergency repairs
  • work to an existing building that either makes it a higher-risk building, or stops it being a higher-risk building

A higher-risk building is a building that has at least:

  • 7 storeys or is at least 18 metres high
  • 2 residential units or is a hospital or a care home

You can read guidance about the criteria that makes a building a higher-risk building.

Principal accountable persons (PAPs)

A higher-risk building with at least 2 residential units must be registered with the Building Safety Regulator (BSR) before people live there.

The PAP must:

  • establish and operate a single MOR system for the high-rise residential building they are responsible for
  • make sure there are regular reviews of the system so it remains effective

When BSR tells the PAP to apply for a building assessment certificate, the PAP must submit information about the MOR system. The information must show that the system allows:

  • reporting and recording of safety occurrences to the accountable person (AP)
  • recording of safety occurrences identified by the AP
  • timely assessment of safety occurrences to determine whether they are a safety occurrence
  • BSR to be notified of safety occurrences as soon as possible
  • safety occurrences to be reported to BSR within 10 calendar days of becoming aware of it

Systems operated by the principal designer and principal contractor

The principal designer and principal contractor must:

  • establish and operate an MOR system before construction or building work begins
  • maintain and operate their system throughout the project

Principal designers and principal contractors can operate the same, or separate MOR systems.

Your MOR system must as far as is reasonably practical, enable prompt reporting by:

  • designers and contractors working on the project
  • others who periodically visit the work site

Find out more about the roles of principal designers and principal contractors in the guide design and building work: meeting building requirements.

Reportable incidents and risks

Your system must let people report safety occurrences that have caused, or if not remedied would be likely to present a risk of:

  • the death of a significant number of people
  • serious injury that needs immediate treatment in hospital or causes a permanent or irreversible disabling condition to a significant number of people

Safety occurrence are incidents or risks involving:

  • structural failure of the building
  • fire safety (design and construction phase)
  • the spread of fire or smoke in the building (occupation phase)

For design work, a building safety risk is an aspect of the design related to structural integrity or fire safety, which if built would be likely to present a risk of death or serious injury to a significant number of people.

You must report safety occurrences that you have assessed and believe meet these criteria to BSR as a safety occurrence. You must do this by submitting a mandatory occurrence:

  • notice, as soon as you can
  • report, within 10 calendar days of the safety occurrence being identified

Operating the MOR system

To help identify safety occurrences, frequent inspections of the:

  • design work must be set up by the principal designer
  • building work must be set up by the principal contractor

You must:

  • promptly review the reports submitted on the system
  • decide if any action is needed

What you must tell people

You must share information about how the system works with:

  • designers, contractors and others working on the project, before they begin any work
  • anyone who enters the work site, as soon as possible
  • BSR, when requested

You should tell people:

  • what they need to report
  • how to make a report
  • how and when the report will be dealt with
  • when they should expect a response about a report they have made
  • how you’ll collect and store information in line with General Data Protection Regulation (GDPR)

It may be helpful to include examples of what people should report on your MOR system.

Systems operated by the PAP

As the PAP, you must establish and operate an MOR system for the building when it is occupied by residents. You must review the system regularly to ensure it remains effective.

Your system must allow quick reporting by:

  • all residents
  • APs
  • others who use the building

Reportable incidents

Your system must let people report safety occurrences that have caused, or if not remedied are likely to present a risk of:

  • the death of a significant number of people
  • serious injury that needs immediate treatment in hospital or causes a permanent or irreversible disabling condition to a significant number of people

Safety occurrences involve at least one of the following:

  • structural failure of the building
  • the spread of fire in the building

The relevant AP must report safety occurrences that meet these criteria to BSR by submitting:

  • a mandatory occurrence notice, as soon as they can
  • a mandatory occurrence report, within 10 calendar days of the safety occurrence being identified

Complaints system

Residents and others may be concerned about something that could cause a safety occurrence in the future and submit it on your complaints system.

If a concern submitted on your complaints system meets the criteria of what to report to BSR, the relevant AP must:

Operating the MOR system

For the parts of the building they are responsible for, the APs must:

  • promptly assess the reports submitted on the system
  • decide what action is needed

What you must tell people

You must share information about how the system works with:

  • all residents
  • APs
  • other users of the building
  • BSR, when requested and as part of applying for a building assessment certificate

To share the information about how the system works, you should publish a policy which tells people:

  • what they need to report
  • how to make a report
  • how and when the report will be dealt with
  • how they can request an update about a report they have made
  • how you’ll collect and store information in line with General Data Protection Regulation (GDPR)

It may be helpful to include examples of what people should report on your MOR system.

You’ll need to describe how and when safety occurrences that have been reported on the system will be submitted to BSR as a mandatory occurrence notice and report.

You should share the latest version of the MOR system policy with APs, residents and other users of the building.

Involving residents

You should involve and consult with your residents when establishing your MOR system. Your resident engagement strategy can help you with this.

Your policy should be clear about how residents and others can submit reports on the system. You should consider if reports can be raised via email, telephone, online and in person.

You must make information about your system easily available and accessible to residents. You can display the information clearly within the building, such as the lobby.

You should consider what to do if residents find it difficult to describe a safety occurrence. They could submit, for example, photo or video evidence that helps communicate what happened.

Your policy should set out what you can do if someone needs information in a different language or in an alternative format. For example, large text, easy read, braille, or audio.

Working with residents to find ways of accessing information that better suits them will help you comply with equality law. When necessary, residents can appoint a representative to report an incident for them.

You should consider consulting with residents on any changes to your MOR system.

Assessing reports made on the MOR system

You should describe how safety occurrences reported on the system will be assessed by APs. You should include this in your MOR system policy.

When assessing a report, aspects to consider include:

  • the details that make up the report
  • if a mandatory occurrence notice and report must be submitted to BSR
  • if the safety occurrence has already been investigated
  • if the report contains additional information relating to a previously raised incident

Updates to this page

Published 31 January 2024
Last updated 6 December 2024 show all updates
  1. This guidance has been updated with information about what principal accountable persons must send to BSR in relation to their mandatory occurrence reporting system.

  2. Information and link added for related guidance about principal designers and contractors

  3. First published.

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