Indice NEMA
The National Electrical Manufacturers Association (NEMA) in the United States also publishes protection ratings for enclosures similar to the IP rating system published by the International Electrotechnical Commission (IEC). NEMA however also dictates other product features not addressed by IP codes, such as corrosion resistance, gasket aging, and construction practices. For this reason while it is possible to map IP Codes to NEMA ratings that satisfy or exceed the IP Code criteria, it is not possible to map NEMA ratings to IP codes, as the IP Code does not mandate the additional requirements.