A standard for most sanitarians, the GE triple range light meter model 217 replaced the 1960s model 214. Basically, they are the same instrument with slight improvements in durability and accuracy. The light meter is selenium cell-based with no batteries are required. It came with a metal diffuser for measuring very bright light and a carry case.
The light meter is color and cosine corrected and is capable of reading illumination from 10 ft-c to 1,000 ft-c on three scales. Its accuracy is between 10% and 15%, depending on the part-of-scale. It is an ideal instrument for measuring Iluminating Engineering Society, Food and Drug Administration model Food Code, Americans With Disabilities Act, and Affordable Care Act illumination standards.