Table A: Material Classification Code

Category : material characteristics	code designation
Density:
Bulk Density	Avg. lbs/CF
Size:
Very Fine — 100 mesh and under	A
Fine — 1⁄8” mesh and under	B
Granular — 1⁄2” mesh and under	C
Lumpy — containing lumps over 1⁄2”	D
Irregular — fibrous, stringy, etc	E
Flowability:
Very free flowing	1
Free flowing	2
Average flowability	3
Sluggish	4
Abrasiveness:
Mildly abrasive	5
Moderately abrasive	6
Extremely abrasive	7
Other Characteristics:
Builds up & hardens	F
Generates static electricity	G
Decomposes — deteriorates in storage	H
Flammability	J
Becomes plastic or tends to soften	K
Very dusty	L
Aerates and becomes fluid	M
Explosiveness	N
Stickiness-adhesion	O
Contaminable, affecting use	P
Degradable, affecting use	Q
Gives off harmful or toxic gas or fumes	R
Highly corrosive	S
Mildly corrosive	T
Hygroscopic	U
Interlocks, mats or agglomerates	V
Oils present	W
Packs under pressure	X
Very light and fluffy — may be windswept	Y
Elevated temperature	Z