CDM Notifiable Projects Working Days And Person Days Explained header image

10th April, 2015

CDM Notifiable Projects Working Days And Person Days Explained

First, let's answer the key question here. What are CDM notifiable projects?

The Construction (Design and Management) Regulations (CDM) apply to every construction project in Great Britain. So, hopefully, if you work in construction, you have at least heard of these regulations. If your not too familiar, we have some free CDM guides to get you up to speed.

But, not every construction project is CDM notifiable.

What are CDM notifiable projects?

Simply put, these are construction projects that need to be notified to the HSE.

If your construction project meets certain criteria (based on project length and the number of people on site, then you have to notify the HSE, and your project is notifiable.

How do we know if your project needs to be notified?

Well, there are two criteria, known as notification thresholds.

If you meet either of these criteria, then your project must be notified.

6. Notification

(1) A project is notifiable if the construction work on a construction site is scheduled to—

(a) last longer than 30 working days and have more than 20 workers working simultaneously at any point in the project; or

(b) exceed 500 person days.

The Construction (Design and Management) Regulations 2015

If your construction project exceeds either one of these thresholds, then it is notifiable under the CDM regulations.

If you're wondering what a person day is or what counts as a working day, don't worry, we're going to break that down for you!

30 working days

What's a working day? Monday to Friday?

It is important to note that under the CDM regulations, a working day is classed as any day on which construction work takes place. Therefore, even if the planned construction work on one day will only be for 2 hours duration, it will need to be classed as a working day when determining if the project is notifiable.

You will need to count weekends if any construction work is likely to take place. For example, if you were planning to do a couple of hours on a Saturday as well as working in the week, then this will count as a day towards the notification threshold.

You can't combine half days either. For example, if you do 8 hours work on a Monday. That's one working day. If you do the same 8 hours work, but carry out 4 hours on a Tuesday, and 4 hours on a Wednesday, that's two working days.

For example, a project lasting 6 weeks with construction work occurring Monday – Friday (5 x 6 = 30) will come in just under 30 day threshold. However, the same project with Fridays work spread across Friday morning and Saturday morning (6 x 6 = 36) will be over 30 working days.

Now, don't forget, under CDM 2015, your project is only notifiable for the 30 working day theshold if you also have more than 20 workers on site any point.

500 person days

A person day is one persons working day.

If we have a project that is 25 working days, and we have 2 people working each of those days, then we have 50 person days.

Some projects have more than one shift per day, for example a day shift and a night shift. So in one day, if you have 10 people on the day shift and 10 people on the night shift, you would have 20 person days.

While 500 sounds like a bigger number, and you might think it would only apply on bigger projects, the 500 person day threshold can apply even for projects under the 30 working day threshold.

A project lasting 20 days does not pass the threshold in the working day test. However if that project was expected to have 40 people on site each day, or 20 people working days and 20 people working nights, then the project would have 800 person days of construction work, and would be notifiable.

Too much math? Use our free CDM notification calculator to find out if your construction project is notifiable!

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This article was written by Emma at HASpod. Emma has over 10 years experience in health and safety and BSc (Hons) Construction Management. She is NEBOSH qualified and Tech IOSH.

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