Damaged rubber on gas masks

[rogueX18]

I have an original M59 (M1) YPA (JNA) gas mask, with the bag and technical sheet.
It is still sealed in the original plastic packing.
However, upon inspection, it seems the rubber developed some damage. I do not know if it is chemical or what, but it looks like small "splotches" or "craters" (<1mm) deep.

Is it maybe a chemical reaction due to the age of the mask? Unfortunately, I do not know how well the mask was stored during the decades.

Also, fellow collectors, do you recommend opening the seal or keeping it as is?
And what would you recommend for wiping dust and preserving the rubber on gas masks?

Thank you!

[HARRY THE MOLE]

Probably just poor moulding of the rubber when it was made. It doesn't look like damage... don't worry about it and leave 'as is.'

[Gunny Hartmann]

Like Steve said, it looks like moulding marks.

[Watchdog]

I agree, it looks like it came out of the mould like that. It's a manufacuring quality issue not deterioration of the rubber.

If you don't open the pack then any treatment of the rubber is obviously not possible. If you do open the package then keeping the rubber dry and out of direct sunlight is the best way to store it. If you apply anything to it at all then you should restrict this to a light dusting of talcuum powder. Basic foot powder is good in that regard because it contains an anti-fungal agent which is an obvious benefit.

This is most likely Silicone Rubber (contains silicone and silicon) which retains it's properties far longer than simple older types of rubber but like all rubber it will deteriorate over time and you can not prevent this.
Having said that, I have a British S6 in my loft that is not wrapped up in any way and which has been there for for nearly 22 years (it was manufactured in the '80s) but is still perfectly fine.

I hope this answers your question.

Regards

Mark

[James C]

I am in total agreement with the comments ,Best way forward would be to keep the mask sealed in my humble opinion RX

[rogueX18]

Thank you all for the information you provided! I will store it as best I can and factory sealed.
I was confused because I once had the same model gas mask (factory sealed), but the rubber melted inside the plastic bag and it was a mess. Probably some manufacturing error or a bad batch, but still...
So I was wondering if this was the start of the same process or not.
Also, is it true that some M2 masks (later, more modern version of this mask) had some issues of melting in good storage?

[James C]

Here is Former Yugoslavian M1 which was exported to Iraq ,high temperatures have affected the rubber compound which you can see on the valve cover ,i also had to use Talc on the inner face mask area because if bagged up folded away for storage and when i have inspected after a time i found the sides would literally be glued together ,so far the talc is working a treat

[rogueX18]

Thank you! Thank you all!