Given that they contain significant amounts of potentially explosive gas and a sparking device that produces highly reactive and hot sparks lighters butane lighters are remarkably safe.

My understanding is that when disposable butane lighter were first sold in the early 70s the airlines wouldn't allow them on flights for fear the pressure change might cause them to explode. There were also stories about unfortunate welder/s who suffered from an explosion when welding slag hit the pressurized lighter. Neither risk was demonstrated and are mostly considered urban myth.

That said there is some risk. Out of curiosity I tossed a full-size Bic into a campfire. I was expecting an explosion worthy of a TV movie. What I got was a pop and flare. I wouldn't want to get too close, burns are no fun, but it isn't really like you're carrying a grenade that might detonate and kill everyone close by.

It isn't a safety tip but I've experimented with spraying silicone on Bic lighters to keep the flint and striker wheel from getting wet with water, which makes striking more difficult until it dries, or corroding in storage. Seems to help. Coating the metal several times with spray silicone, allowing each coat to dry before respraying, makes water shake right off.

Corrected for spelling. One of these days I'll learn how to write and edit before I post.