The best answer I could find was when you Google it, that the fuse is of poor quality. I cannot leave you a link, but you can find it for yourself. Put in poor quality fireworks and all sorts of things will pop up. No pun intended.
<span>Air pressure decreases as you move higher in the atmosphere. Think of a column of air directly over your body. ... Just as air pressure decreases with altitude, so does the density of air.</span>
