The National Electrical Manufacturers Association (NEMA), on behalf of The American National Standard Lighting Group (ANSLG), has published ANSI/ANSLG C81.61-2009 Electrical Lamp Bases - Specifications for Bases (Caps) for Electric Lamps and ANSI/ANSLG C81.62-2009 Electric Lampholders. Both documents were last revised in 2007.

C81.61 and C81.62 respectively cover lamp bases (caps) and lampholders for electric lamps. Both standards were revised to include G24 lampholder and base dimensions.

ANSI/ANSLG C81.61 may be downloaded at no charge, or a hardcopy purchased for $380, by visiting www.nema.org/stds/c81-61.cfm.ANSI/ANSLG C81.62 may be downloaded at no charge, or a hardcopy purchased for $280, by visiting www.nema.org/stds/c81-62.cfm. Both may also be purchased by contacting IHS at 800-854-7179 (within the U.S.), 303-397-7956 (international), 303-397-2740 (fax), or global.ihs.com.

NEMA is the association of electrical and medical imaging equipment manufacturers. Founded in 1926 and headquartered near Washington, D.C., its approximately 450 member companies manufacture products used in the generation, transmission and distribution, control, and end use of electricity. These products are used in utility, industrial, commercial, institutional, and residential applications. The association’s Medical Imaging & Technology Alliance (MITA) Division represents manufacturers of cutting-edge medical diagnostic imaging equipment including MRI, CT, x-ray, and ultrasound products. Worldwide sales of NEMA-scope products exceed $120 billion. In addition to its headquarters in Rosslyn, Virginia, NEMA also has offices in Beijing and Mexico City.