If your bag isn’t tempature rated to last until above 177C then you are creating a failure situation where you have destroyed your media while trying to protect them.

For reference:
ETL fire rating spec: http://www.sentrysafe.com/products/testingAndStandards/media.aspx

The moral of the story is store stuff where it is ment to be stored and don’t provide extra protection unless it is designed for that purpose. If you are worried about water, then buy the proper safe, or store it in a Safe Deposit Box.

DVDs and such are not good long term storage anyways, use Google Docs, or another offsite backup solution for any backup that actually matters to you.

Lifespan of CD-Rs 5-10 years (organic failure)
Lifespan of DVD-Rs 5-10 years (also organic failure)
Lifespan of Blu-Ray 50-100 years (all metal).
All of these media items slowly degrade and fail, always duplicate and backup again all precious CDs, DVD periodically. Top end media (not discount brands) can add 5 or more years to the lifespan of a CD or DVD.

Putting DVDs and USB sticks in water is not a good idea, as water dries and leave marks which will scatter the reading LASER, or will corrode USB sticks. So you might as well put them in a water tight bag and rely on off-site backup in case of fire.

A ziplock back will melt at a much lower tempature than a DVD. Causing a case where your protection causes more damage than it stops.

DVDs should be in ziplock bags. If it’s hot enough to melt the bag, the DVD would be melted too. The bag protects against water. Anyways, you should store copies in at least two places (eg: home and bank, or home and parent’s house).

Paper: if your “paper” is a rare first edition of Darwin’s Origin of Species, then yes it should be in the bank. If it’s just official papers (money, passport, birth certif.) then getting it wet is no problem. It retains all value when dried.

Try throwing a CD/DVD into an oven at 350F and see how they fair. That is the rated max temp in a fire rated safe. A media rated safe will keep the temp much cooler, yet still hot enough to melt photographs.

Never store anything in a safe that the safe does not explicitly state will be ok. Otherwise you will have problems.

Keep copies of all important documents. I recommend 3 copies min. 1 in your filing cabnet, 1 in your safe, 1 in your saftey deposit box. For “things” like jewelry, get insurance. Irreplaceable stuff like photographs you need to get copied and store them in a few locations to ensure sufficent protection.

To ensure 100% protection of your valuables you need to be very paronoid. Or just decide what you can live without and cut back a little bit. Peace of mind is worth a lot of money, unless of course you don’t have it, then you just have to make due with what you can scrape together.

2- Storing hard drives in a safe is a sure way to lose data. After a medium-while of sitting there unused, the bearings will seize and it will be unusable. Use USB sticks, CDs, or DVDs. Even those may only last 5-7 years. Ideally you constantly use “rolling backups” and large parity files.

3- Put your safe in your basement, elevated on 2 feet of bricks. Put DVDs, etc in ziplock bags. Papers: who cares if they get wet.

Quality safes are drop rated. There are 2 ratings commonly used 15 feet and 30 feet. Basically 1 or 2 stories. The rating means that the safe has been burned for the entire fire rating period, then dropped and did not burst open, also the rated contents were then retrievable.

I like the idea of storing the safe in the basement, I have found that if the safe is not reasonably accessible I personally will not use it. My safe is over 500 lbs so I feel reasonably comfortable with the unlikelyness of someone trying to steal it (plus a home alarm…). If I don’t use the safe for valuable documents (the number 1 reason for a safe) I might as well not have one.