The National Electrical Manufacturers Association (NEMA) has published NEMA 77-2017 Temporal Light Artifacts: Test Methods and Guidance for Acceptance Criteria. Temporal Light Artifacts (TLA) are defined as “undesired changes in visual perception induced by a light stimulus whose luminance or spectral distribution fluctuates with time, such as flicker and stroboscopic effect.” According to the release: “This new lighting standard makes recommendations on methods of quantifying the visibility of TLA, and initial, broad application-dependent limits on TLA.”

In a prepared statement, Jim Gaines of Philips Lighting and chair of the NEMA 77 working group said, “Besides adjusting visible light output, many dimmer designs can react with LED light engines to produce additional light modulation in the form of TLA. NEMA 77 provides a method to quantify the likelihood that a given light modulation might produce observable TLA, and employs a measurement framework that allows for further refinement to develop application-specific guidelines.”

The document is available for purchase from the NEMA website [see link below] in either a hard copy version or as an electronic download.