| PROPERTY | TEST METHOD | FOSTA-TEK ADC
 (CR-39)
 | COATED POLYCARB | COATED ACRYLIC | CAST POLYESTER | CROWN GLASS | 
        
            | OPTICAL Transmission %
 Refractive Index
 Haze %
 Yellowness Index
 | ASTM D1003
 ASTM D542
 ASTM D1003
 ASTM D1925
 | 92
 1.50
 .3-.9
 .6-1.4
 | 89
 1.58
 .5-1.0
 .8-1.0
 | 89
 1.46
 2.0
 1.5-2.0
 | 88
 1.55
 2-4
 2.0-3.0
 | 92
 1.52
 .3
 .6
 | 
        
            | PHYSICAL/MECHANICAL Specific Gravity
 Flexural Strength
 Hardness Rockwell M
 Impact Strength
 Abrasion Resistance
 | ASTM D792
 ASTM D790 x 1000PSI
 ASTM D1044 & D785
 ASTM D256
 Taber x Acrylic
 | 1.31
 7.5-13.0
 95-100
 .2-.4
 15-20
 | 1.20
 13.5
 70
 16
 .2
 | 1.19
 14.6
 93
 .4
 1
 | 1.38
 8.6
 91-95
 .25
 4
 | 2.50
 1.8
 N/A
 N/A
 N/A
 | 
        
            | THERMAL Thermal Expansion
 Thermal Conductivity
 Heat Distortion (C)
 Operating Temp
 UL Flammability Class.
 | ASTM D696
 ASTM C177
 ASTM D648 @ 264PSI
 Continuous (C)
 UL Labs.
 | 8.1-14.3
 4.8-5.0
 130
 100/148*
 UL94HB
 | 3.75
 1.35
 132
 97
 UL94V-2
 | 2.7-4.3
 0.9
 82
 65
 UL94HB
 | 7.15
 4.0
 104
 110
 UL94HB
 | 4.0-6.0
 0.4-0.6
 N/A
 N/A
 N/A
 | 
        
            | ELECTRICAL Dielectric Strength
 Dielectric Constant
 | ASTM D149
 ASMT D150
 | 380
 4.2
 | 1700
 2.99
 | 500
 3.7
 | 382
 3.5
 | 760
 2.9-3.5
 |