It'd be helpful to state how long the fire will burn instead of the current "You can not walk through the fire" warning that you only need to hear once in a player's lifetime.
I see how it can help in some cases and in my games I personally had a need to be on a particular spot however this happened maybe only a handful times; it is not a typical need for me, I wonder if it is for you and others?
On my mind, it is way more likely that the instruction to walk into fire was a mistake rather than a deliberate attempt to get engulfed in flames or a desire to be exactly on that particular tile for any reason. With this background, I doubt that information would be helpful for typical use case as I cannot imagine many/most players will have a need to sit there and wait.
And for those who do, since we currently already have a system that allows a player to find out WHEN will fire in a particular tile die out [i.e.: EXAMINE command with 'F3' or 'l'], pushing down this information to any player who most-likely-mistakenly attempts to step into to a live fire is not only unnecessary/unhelpful but also cluttering and spammy.
edit: typofix