I was wondering if we could make a campfire, and then in an emergency, scoop said fire into the bag of holding to prevent the smoke from giving away our position.

Are they fireproof from the inside?

No, it is not fireproof

The general rules for damaging magic items says:

Most magic items, other than potions and scrolls, have resistance to all damage. Artifacts are practically indestructible, requiring extreme measures to destroy. (DMG 141)

Thus, most magic items (of which a bag of holding is one) are in fact only resistant to fire damage and not fireproof (immune to fire damage).

The bag of holding does not give any indication that it is an exception to this and, in fact, details some additional ways it can get damaged:

If the bag is overloaded, pierced, or torn, it ruptures and is destroyed...

So, by default, this item is not fireproof which makes sense because it is still just a bag (albeit a magical one). As always, your DM is more than welcome to rule otherwise though.

Exactly how much damage scooping a fire into the bag would do to it and how long it would burn in there (it has a limited amount of oxygen) will be up to your DM. Given that it does have resistance (and depending on how much damage the fire does), you might be able to get away with this trick once without actually destroying the item (which only would happen when you bring its HP to 0).

Probably not.

The rules text for the bag of holding say,

If the bag is overloaded, pierced, or torn, it ruptures and is destroyed...

It doesn't actually say 'burned'. So are piercing and tearing the ONLY things that can destroy a bag of holding, or is any physical damage sufficient, and this represents an additional rule of some kind?

On p.141 of the Dungeon Master's Guide, we have the "Magic Item Resilience" rule, which says items are "at least as durable as non-magical items of their kind", and generally "have resistance to all damage". Resistance is not immunity, and normal bags aren't immune to fire, so the bag clearly can be burned; but we don't know how much damage is necessary to destroy a normal bag. (It probably isn't much.)

It seems to me that the intent here is, despite being magical, the bag is still essentially a bag, and can be destroyed by things that would damage or destroy a bag's physical form. This would include burning -- I suspect the specific rule about piercing and tearing is merely saying such effects are extra destructive to a bag of holding -- maybe the bag doesn't get resistance against those damage types.

In any case, it seems clear that fire can indeed harm a bag of holding, but it's up to the DM as to how much damage it would take to destroy the bag.

There are ways to build fire so that the smoke does not rise into a straight column, but instead is diffused and thus less perceptible. For example, look at the Dakota Fire Pit which is according to the author detailed in both the US Army Survival Field Manual and the Ranger Handbook.

The essentials are that:

• The fire is in a pit, with no visible flame above ground giving away your position.


• The fire burns hotter, so there is less smoke.


• The pit should be located close to the base of a tree, so that the smoke is dispersed by the branches instead of rising in a clear column.


• "Dousing" the fire is as simple as dumping sand/clay in both the main pit and the fresh air chimney (no water!).

And all that, and more, should be covered by a Wisdom (Survival) check. I just added the details to improve your role-play description.

I've used this in the past in the 3.5 edition; with the following understanding:

• Small and smart parties would tend to try and hide their fire outside of their territories, to avoid getting spotted from miles at night. It was implicit that the party would use this method by default, unless otherwise specified.


• At close proximity, the smell of the smoke could still be detected, though I do not remember the exact distance, it was affected by the direction of the wind: half-distance upwind, double-distance downwind.


• If not built correctly, it could potentially still be seen (directly or indirectly), which a Spot vs Survival check covered, with usual modifiers in the forest, etc...

As an adaptation to 5.0, I would expect that only someone who has experience traveling in the wild in small parties would know of this: something you would expect from a Barbarian or Ranger and the Outlander background or the Solider (Scout) background, but not from a Fighter with the Sailor background.

And from a check point of view, an opposed roll between Wisdom (Perception) and Wisdom (Survival); with some Advantage/Disadvantage based on terrain conditions -- easier to hide in a dense forest rather than on rolling plains -- and wind direction.