Can any fire glass be used in a Bond outdoor heating unit?

Yes, while Bond provides many filler options, any fire glass with a minimum size of ½ inch can be used safely. Bond does not recommend using ¼ inch fire glass in outdoor heating units as the smaller glass pieces can clog the burner and ignition guard. The entire firebowl should not be filled with fire glass alone. The base of the fire pan should be filled with lava rock to allow for better air circulation.