The National Electrical Manufacturers Association (NEMA) published ANSI/NEMA C29.2A-2013
Wet Process Porcelain and Toughened Glass—Distribution Suspension Type
and ANSI/NEMA C29.2B-2013
Wet Process Porcelain and Toughened Glass—Transmission Suspension Type.
ANSI/NEMA C29.2A covers distribution suspension-type insulators 4.25 inches (108 millimeters) to 8 inches (203 millimeters) in diameter, made of wet-process porcelain or of toughened glass, and used in the distribution of electrical energy.
C29.2A may be purchased in electronic or hardcopy format for $45.
ANSI/NEMA C29.2 B covers transmission suspension-type insulators 9 inches (228.6 millimeters) in diameter and larger, made of wet-process porcelain or of toughened glass, and used in the transmission of electrical energy.
may be purchased in electronic or hardcopy format for $59.
Contents and scope of each standard may be viewed on the
The National Electrical Manufacturers Association (NEMA) represents 350 electrical and medical imaging manufacturers at the forefront of electrical safety, reliability, resilience, efficiency, and energy security. Our combined industries account for more than 400,000 American jobs and more than 7,000 facilities across the United States. Domestic production exceeds $114 billion per year and exports top $50 billion.