LED retrofit luminaire conversion kits were created to convert the millions of installed luminaires provided with other types of light sources (incandescent, fluorescent, HID, etc.) to energy efficient LED Luminaires. Certified (Classified) retrofit kits installed in accordance with their installation instructions into the identified Listed (Certified) luminaires provide a method to Certify (Classify) the combination of the host luminaire and the retrofit conversion kit to comply with the host luminaire Certification (Listing) requirements and the Certification (Listing) requirements for luminaires and retrofit kits in the National Electrical Code (NEC). These FAQs are intended to help answer many questions that code authorities and installers may have regarding retrofitting luminaires and converting them to an LED light source while maintaining compliance with Certification (Listing) requirements.