Strain type insulators, and this standard applies to polymer, suspension insulators used to construct 115 kV transmission lines.

Insulators shall meet the applicable requirements of the following national standards:
ANSI C29.1 Test Methods for Electrical Power Insulators
ANSI C29.2 Wet Process Porcelain and Toughened Glass - Suspension Type
ANSI C29.11 Tests for Composite Suspension Insulators for Overhead Transmission Lines
ASTM A153-1982 Zinc Coating (Hot Dip) on Iron and Steel Hardware

Insulators shall be packaged in wood crates to protect against physical damage that could occur during shipping, handling, or long-term outside storage. Insulator weather sheds shall not bear any load due to its own weight or that of insulators or crates above or below it.

Strain type insulators, sheath material must be composed of at least 33% silicon by weight.

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