F10 Notification: What It Is, When You Need It and How to Submit

The F10 notification is one of the first CDM 2015 obligations for any notifiable construction project — and one of the most frequently mishandled. It's not complicated, but it needs to be done correctly and at the right time. Here's everything you need to know.

What is the F10?

The F10 is the formal notification to the Health and Safety Executive (HSE) that a notifiable construction project is about to begin. Under CDM 2015, the client is responsible for ensuring the F10 is submitted. In practice, this duty is usually carried out by the project manager or client representative on the client's behalf.

Once submitted, the F10 notification must be displayed prominently on site for the duration of the project. It's one of the first things an HSE inspector will look for on a site visit.

When is a project notifiable?

A project is notifiable if the construction phase will last longer than 30 working days with more than 20 workers working simultaneously at any point, or if it will exceed 500 person-days of construction work in total.

If you're unsure whether your project is notifiable, the default position should be to notify. The consequences of failing to notify when required are significantly worse than notifying when it wasn't strictly necessary.

When should it be submitted?

The F10 should be submitted as early as possible — ideally before the construction phase begins, and certainly before the Principal Contractor mobilises on site. If project details change significantly — for example, if the Principal Contractor changes or the project scope increases substantially — the F10 must be updated.

How to submit

The F10 is submitted online through the HSE website at hse.gov.uk/construction/cdm. You will need the project address and description, the client's details, the Principal Designer's and Principal Contractor's details, and the planned start date and duration. The HSE does not charge for F10 submission.

Once submitted, save a copy of the confirmation for your project SHE folder alongside the Construction Phase Plan and Pre-Construction Information.

Common mistakes

The most common F10 mistakes we see:

• Submitted after the construction phase has already started
• Not updated when the Principal Contractor changes mid-project
• Not displayed on site — it must be posted prominently for the project duration

All three can attract HSE enforcement action. None are difficult to avoid with a proper pre-start process in place.