Calculating Capacity / Width of exit doors

[Meady]

Please can we have some guidance on interpreting ADB - this is for a brand new village hall so we are using ADB Vol. 2 and specifically looking at tables 2.2 and 2.3.

We have established and agreed with the architect that the capacity based upon 1m/person density is 165.

So looking at table 2.2, we need at least 2 exit doorways.

What we are struggling with is the widths.  Reading Table 2.3, we need to deduct the largest doorway and use the remaining door width for the calculation.

Does the remaining door width after we have discounted the largest then need to be no less than 1050mm as we have more than 110 but less than 220??

Please can anyone explain what Note 3 means when it says "Widths less than 1050mm should not be interpolated"?? 

Are we correct in saying the 5mm rule / person does not apply for any door width less than 1050mm too?  

Thank you in advance for your help / guidance.

[AnthonyB]

Whilst it wouldn't win a Plain English reward, it is indeed saying the 5mm/person rule is only for doors over 1050mm

[Meady]

? thank you AnthonyB - are we correct in our other calculations and that the remaining width must be no less than 1050mm after we have deducted the largest door for 165 people?

[AnthonyB]

I've just realised - this is a new build that's still on paper?

You may benefit from designing to BS9999 and not Approved Document B - it is more generous and flexible in it's approach.

[Guest Perkie]

So does that mean if a door is 1550mm, its 220 people for the first 1050, then the extra 500mm is divided by 5mm equalling 100 more people?

or 1550mm divided by 5mm equalling 310 people?

[Mike North]

1550mm divided by 5mm equalling 310 people