Project Description

Invited by LED manufacturer, in conjunction with Seattle Mariners’ head of facilities, to serve as independent evaluators, to measure and validate light levels on the entire baseball playing surface following installation of new LED field lighting.  Safeco Field was the first Major League Baseball stadium to install LED field lighting.

GOAL: Confirm compliance with MLB required light level specifications.


  • Kurt and two Lighting Design Lab colleagues conducted a detailed photometric measurement study of light levels according to MLB’s standard procedures for measuring light levels.
  • Scotopic light levels, which are perceived differently by the human eye, were also measured, as requested by the LED manufacturer.
  • The independent measurements were taken just prior to MLB’s own measurements being taken by its light evaluators.