In my search for ways to have safer trash burning I found that a dryer drum both fits on a 55 gallon burn barrel, but also has holes that allow airflow, but prevent burning materials from escaping.
By placing the dryer drum on the burn barrel I can more safely burn items without fear of stray burning bits causing a fire. So far the only problem is that the drum gets hot, and so it is hard to remove for reloading of the barrel.
However, I figure that if I am constantly dumping items in the fire then I am there to watch it, but If I just am filling it up to burn a set amount of items then this is effective.
As a side benefit, the extra metal heating up more efficiently transfers it if you are burning to keep a warm spot to stand around on a cold winter day.
Covered burning is pretty important – vital even depending on the time of year.