This Aerospace Recommended Practice sets forth the guidelines for the use of non-black O-ring seals. Black is the preferred color for polymer types other than Silicone and Fluorosilicone. When a color other than black is to be used, those established by this document are the preferred.

PURPOSE:

To establish colors for primary polymer types when black is not used; Chloroprene, Fluorocarbon, Ethylene Propylene, Silicone, Fluorosilicone and Fluorophosphonitrilic.

To reduce the possibility of mixed polymer types during storage.