Table 2.
Flame retardancy of plywood treated with difference water glass concentration

Sample	Remaining flame time (sec)	Smoldering time (sec)	Carbonized area (mm2)	Carbonized length (mm)
	less than 10 sec	less than 30 sec	less than 5,000 mm2	less than 200 mm
	A	0	0	16,524	201
B	0	0	14,659	189
C	0	0	8,454	167
D	0	0	8,590	164
E	0	0	2,589	70