[crosspost] [Question] Gas mask (for smoke)

https://lemmy.world/post/2313051

With all these fires going around and the potential of house fires a quick question about gas masks.

Is the RD40 40mm thread EN-148-1 the same as the STANAG 4155 Nato thread?

Would a draeger rd 40 filter fit a MP5 Gas mask ? Or a military nbc filter fit a draeger x-plore-6300?

Edit: Just want to know if the civilian and mil spec threading is identical.