I can't help you out with fire but for water, the watershed bags are rugged and durable bags rated at 200 ft sea water. I store all my critical gear in these bags including 2 wm down bags. I have no concerns about water issues with these bags and I can use them as a flotation device to cross over a deep river. Worth the money and they stand behind there work. If you do decide to get one, pay the money for the purge valve. It really lets you remove the air out and it stays out, or inflate them for a flotation device.

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