ISO Class

ASTM Class

Test Results

Peeling area ratio

S

0

5B

The incision edges are smooth,

without any peeling

S=0%

1

4B

The incision at the crossing

of minor peeling

0＜S≤5%

2

3B

The incision edges and the crossing

of a small piece of peeling

5%＜S≤15%

3

2B

The incision edge and the crossing 

of a piece of peeling

15%＜S≤35%

4

1B

The incision edge and the crossing

of large piece of peeling

35%＜S≤65%

5

0B

The incision edge and the crossing 

of a large piece of major peeling

65%＜S