Based on the NRA-NMLRA Basic Muzzleloading Shooting Course, I’ve included some information for RSOs on general safety practices for this category of firearm.

1. A traditional ECI will not work with a muzzleloader.  The next best thing is to have the firearm’s ramrod with a mark to show the barrel is empty, have the hammer in halfcocked position, and to have the nipple for the percussion cap exposed or no powder in the pan (flintlock). 
2. If the ramrod is not marked, then measure it from the outside, bringing the tip near the hammer end of the barrel and marking the rod at the end of the muzzle.  (piece of tape is fine). 
3. For a misfire, wait the two minutes and if nothing happened, you’ll have to observe/supervise the user to render the charge inert and remove the ball. 
   1. Half cock the hammer (closest thing to a safety)
   2. Render the charge inert:  pour water or Windex (windshield wiper fluid) down the barrel to soak the powder charge
   3. Remove the ball:  Best is to use a CO2 device to blow the charge and ball out of the muzzle.  (the user may have one or someone on the range) IF no CO2, then the user must use a ball remover.  It is a pain and difficult but it will come out. 
4. Experienced muzzleloaders/black powder shooters might believe some the procedures we require are not necessary because in their experience nothing wrong has ever happened.  These points are designed to reduce the probability of a mishap as close to zero as possible or to deal with a mishap in the safest possible manner.