CDM Notifiable Projects Working Days And Person Days Explained header image

15th August, 2019

CDM Notifiable Projects Working Days And Person Days Explained

If a construction project meets the notification criteria, the HSE want to know about it. Does your construction project need to be notified to the HSE? To know the answer to this question, you need to know about working days and person days.

Some construction projects in the UK have to be notified to the HSE. These are projects that meet certain thresholds, in terms of how long the project will take, and how many people are working on it.

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.

Just need to know if your project is notifiable? Use our free CDM notification calculator to find out!

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 your site) then you have to notify the HSE, and your project is notifiable.

Under previous versions of the CDM regulations, having a notifiable project meant extra requirements. But, under the current 2015 version, the notification doesn't make a big difference. Now, all construction projects need a construction phase plan. And all projects with more than one contractor need a principal designer and principal contractor. If your project is notifiable, it means just that. Your project needs to be notified to the HSE. This is on top of the other duties you need to comply with, regardless of project size and duration.

Still, if you fail to notify, you could be a bit of trouble. It's in the regulations, so it's a legal requirement.

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

  1. last longer than 30 working days and have more than 20 workers working simultaneously at any point in the project; or
  2. exceed 500 person days.
The Construction (Design and Management) Regulations 2015 Notification

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? What if you only work weekends. What about evenings, do they count?

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.

Just working a Tuesday evening? That's 1 working day. Just doing an hour on a Saturday? That's 1 working day.

A working day is any day on which construction work takes place

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 an extra 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 the 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 threshold if you also have more than 20 workers on-site at any point.

500 person days

The second criteria, and possibly the more common of the two under the latest version of the regulations, is 500 person days.

A person day is one persons working day. Each day a person works, they clock up one person day under CDM.

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

Working Days x People = 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.

The same rules apply to person days as they do under working days. Partial days count as working days. However, to calculate these as person days, you multiply your working days by the number of people on site. If somebody works for an hour on a Saturday, that's one person day. If two people work for an hour on a Saturday, that's 2 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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