yn9man makes some very good points above, but I have to take issue with the following:
When an item (sleeve / pages etc.) reads / says "photo safe" it doesn't always mean it is "acid free" Must say "acid free" to in fact be "acid free".
Store albums flat not upright.
I said above that
"acid free" is not a reliable indicator of long-term stability. This is why: the term is not a regulated one. Anyone can say that anything is "acid free" and it is not checked by any regulating body. All the term "acid free" means in a reliable sense is that the product, when it left the manufacturer, was not of an acidic pH (i.e. below 7). It does not mean that the product will not develop acidity as time goes by. It is entirely possible that something called "acid free" will become acidic as it ages, due to what it is made from.
It's particularly frustrating when it is applied to plastics, where acidity is often not the concern. The old standard PVC (polyvinyl chloride) releases chlorides and plasticisers which discolour and damage things like photos in their vicinity. Acetates do release acid as they age, but again it's the plasticisers that are released as it ages that are the problem.
"Photo safe" is not a regulated term either, but it can be a better indicator of archival quality.
But as already stated,
if the item has passed the Photographic Activity Test (PAT) then it has been tested by an accredited facility and is certified safe to use as packaging or housing for photographic materials.
Regarding storing albums flat, not upright...this is appropriate for old albums, in order not to stress the bindings too much. But for the newer kind, storing upright can be totally safe. In fact, some (like the polypropylene binder type, with plastic sleeves) are best stored upright, with the binding at the top, so the pages hang down and there is no pressure on the photographs at all.
Not wanting to confuse anybody, but I hear the acid free thing all the time in my job as a paper and photograph conservator, and it irks me that it can be used by disreputable firms to mislead customers into thinking they are buying an appropriate product.
Cheers
Prue
