Flamable fabrics?

I wonder about the flammability of lightweight fabrics and campfire safety. In particular I have a friend who hikes with denim jeans so that he won't have a literal melt-down beside a campfire. He thinks my nylon zip-offs should not be anywhere near a real fire.
What do you think?

Hot embers that pop out of a campfire can easily burn a hole in your nylon pants, but they won't set them on fire or even make a hole much bigger than the size of the ember that caused it. They are usually a bit bigger than a pin head.

I think the potential risk of hypothermia from cold, wet, jeans is greater than the risk of self immolation from a stray spark on nylon. And, both of these risks are probably less than that assumed when driving to the trailhead.

In the heat of summer when I would be wearing nylon pants, the fire is kept very small. In colder weather when heat from the fire is desireable, I wear lightweight wool pants. These mitigate melting (nylon), and burning (cotton), and also are much better than cotton or nylon when damp/wet. Easier to dry out by the fire due to wool's fire retardant properties.

hmmmm. In the last ten years and 2,000 miles of backpacking, we've made a fire exactly twice. But that's more than the number of times we're worn heavy, water absorbing denim pants on a hiking trip.

Im the same as the above poster. I pretty much only wear nylon pants, never jeam. If you get wet then you will be cold
I also never build fires when backpacking. Too much work after backpacking,all day. I get my from what i wear, what i eat and my sleep system

Sewing for Civil War reenactments has taught me a lot about fabrics. Since there was no nylon/polyester/rayon/etc. in 1860, and fabric labeling isn't all it should be, we run burn tests on scraps of fabric to make sure we don't have synthetic fabrics. Here are the results:

Cotton burns rapidly, with a good flame. Don't let anyone tell you it's fire resistant, unless it has been chemically treated.

Synthetic fabrics don't burn; they melt, leaving a sticky, clingy residue. This residue shows up on burn tests even if the percentage of synthetic fabric in synthetic/cotton or synthetic/wool blends is very small.

Wool, on the other hand is relatively fire-resistant. Sparks may burn a hole, but it's a lot harder to sustain a flame than with cotton.

Applied to backpacking--I wear nylon pants. They dry rapidly from just my body heat. Jeans are hazardous when wet because they take so long to dry (what's the last piece of clothing to come out of the dryer?). Wet denim also clings to the body, restricting movement.

I don't build fires either when backpacking. Here in the Pacific NW, the hiking season corresponds with the dry season, when open fires are not allowed. I also prefer being at high altitude (naear to above timberline), where fires are also not allowed.