Sanity check. Is this pressure treated timber?

[OldKettle]

Hi,
I've just bought a few lengths of pressure treated C24 timber from a local builders merchant.

They are all 2x6, but a mix of 4.8 metres and 3.6 metres.

It wasn't until I got home that I noticed that there is a big colour difference between the two lengths, and this has gotten me wondering whether there are both pressure treated.

To my untrained eye the 4.8m lengths are the same colour as other pressure treated timber I have previously bought and the 3.6m lengths are the same colour as untreated timer I have bought.

I think they must all be treated because as far as I call tell that merchant only sells treated version, but the colour is making me doubt myself.

Below are some pictures of both lengths (the 4.8m being the darker ones) with the stamps also shown.

Any advise would be much appreciated before I start working with it.

 

[Deleted member 174758]

The problem is that whilst the treatments used normally have a dye stuff added (generally yellow, brown or green, although pink and blue are sometimes seen) treated timber can also be ordered as "face visible" in which case because the timber will be seen it is treated without dye being added.

 

[^woody^]

You'll need to ask the supplier what process they used.

Tanalith based preservatives are green or brown but there are also some such as Vascol which are clear.

Your also need to be sure that the preservative is the right one for the use and location of the timber. Generally the clear types are the lowest grade and for dry situations only. Tanalith can be used in damp conditions.