ASTM Tests for Mineral Insulating Oil
Physical tests
Aniline point: ASTM D611
Color: ASTM D1500
Flash and fire points: ASTM D92
Interfacial tension: ASTM D971, ASTM D2285
Pour point: ASTM D97
Relative density (specific gravity): ASTM D1298
Viscosity: ASTM D88, ASTM D445, ASTM D2161
Visual examination: ASTM D1524

Electrical tests
Dielectric breakdown voltage: ASTM D877, ASTM D1816
Dielectric breakdown impulse voltage: ASTM D3300
Dissipation factor (power factor): ASTM D924
Gassing of insulating oils under electrical stress and ionization: ASTM D2300

Chemical tests
Gas content: ASTM D2945, ASTM D3284, ASTM D3612
Polychlorinated biphenyls: ASTM D4059
Corrosive sulfur: ASTM D1275
Neutralization number (acidity): ASTM D664, ASTM D974
Oxidation inhibitor content: ASTM D2668, ASTM D4768
Oxidation stability (inhibited oil only, pressure vessel), oxidation stability: ASTM D2112, ASTM D2440
Water in insulating liquids: ASTM D1533
Furans in insulating liquids: ASTM D5837