We encourage you to consider using burn racks for your Class A live fire training evolutions.

Using burn racks is an important consideration as:

1. They pick the heat up off the floor.  It is common practice to maintain a bed of hot embers throughout the day by not extinguishing fuel loads while conducting successive evolutions.  This facilitates ignition of the next evolution.  However, that bed of smoldering fuel can cause fairly serious temperatures to conduct through floor coverings (frequently a layer of fire brick) and into the underlying structural concrete.  Those temperatures can cause problems.  By using a burn rack that is just a foot off the floor, you can generally reduce or eliminate this issue.
2. They define a fuel load.  Now that NFPA 1403 requires you to define fuel packages and numbers of evolutions, why not design your burn racks to accommodate maximum fuel loads that you have specified?  Racks can help your staff control and promote safety by controlling the quantity and configuration of fuel.
3. They move the fire away from the walls.  The point is obvious.  This helps lengthen the life of your walls.

All these things help to protect the live fire training structure, as well as your personnel.

It is not necessary to spend a bunch of money on fancy burn racks.  Keep it simple.  Buy them locally, or fabricate them yourselves.  Talk to your peers for ideas.  Let us know if you need assistance, and we can probably plug you into another fire department that is already doing what you are trying to figure out.  Don’t hesitate to use us to network with your peers.