Jump to content
Sign in to follow this  
sloth

5837 rpa's?

Recommended Posts

sloth   

Ok, maybe I am looking at this wrongly through sleep deprived eyes, but:

- BS5837 section 4.4.2.6 says measure stem diameters to the nearest 10mm

- section 4.6.1 says diameters measured in accordance with annex C, and RPA determined from annex D

- annex D has diameters in increments of 25mm, so that RPA radii (is that even a word?!) increase by 0.3m a time, for ease of laying out protection on site presumably.

 

Should RPA's be taken from annex D, or is it just a guide? Or, should they simply be plotted on the TPP as 12 times stem diameter?

Thoughts and opinions please.....

Share this post


Link to post
Share on other sites
Beezy   

I think that Annex D has been added to the recently revised BS5837 in order to simplify things a bit tbh.

 

So from my understanding, you measure the stem diameter and round the figure up to the nearest increment in Annex D, and plot the RPA (radius or area) using that.

 

I use software that does it for you ;)

 

My opinion on it anyway, hope this helps

Share this post


Link to post
Share on other sites

The thinking behind rounding up RPAs to the nearest 10mm is to try and stop people submitting reports with RPAs specified to the nth degree. I imagine most people calculate the RPAs using a formula in Excel but don't bother to edit it to a sensible level of accuracy before copying the tree data table in to their reports!

 

The table in Annexe D makes it easier to determine a RPA without doing the calculations yourself, but personally I'll still use my own calculations as I find this quicker.

 

The fun(!) bit is doing the maths for multi-stemmed trees now!

Share this post


Link to post
Share on other sites
sloth   
I think that Annex D has been added to the recently revised BS5837 in order to simplify things a bit tbh.

 

So from my understanding, you measure the stem diameter and round the figure up to the nearest increment in Annex D, and plot the RPA (radius or area) using that.

 

I use software that does it for you ;)

 

My opinion on it anyway, hope this helps

 

 

that makes sense, however I can't find any reference to say you must round up to the nearest increment in annex D?

 

 

 

 

The thinking behind rounding up RPAs to the nearest 10mm is to try and stop people submitting reports with RPAs specified to the nth degree. I imagine most people calculate the RPAs using a formula in Excel but don't bother to edit it to a sensible level of accuracy before copying the tree data table in to their reports!

 

The table in Annexe D makes it easier to determine a RPA without doing the calculations yourself, but personally I'll still use my own calculations as I find this quicker.

 

The fun(!) bit is doing the maths for multi-stemmed trees now!

 

I am trying to set up an Excel spreadsheet to do it for me, somehow incorporating the rounding to annex D figures, if need be. And yes, multistems can be a pita...

Ta

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Featured Adverts

About

Arbtalk.co.uk is a hub for the arboriculture industry in the UK.  
If you're just starting out and you need business, equipment, tech or training support you're in the right place.  If you've done it, made it, got a van load of oily t-shirts and have decided to give something back by sharing your knowledge or wisdom,  then you're welcome too.
If you would like to contribute to making this industry more effective and safe then welcome.
Just like a living tree, it'll always be a work in progress.
Please have a look around, sign up, share and contribute the best you have.

See you inside.

The Arbtalk Team

Follow us

Get in touch

facebook feed

Recent tweets

×