Upcoming Event

Zonal Cavity Method Problems with LED fixtures: A Proposed Solution for Lighting Layouts
Presented by: Sri Rahm, Senior Lighting Application Specialist — GE


The Zonal Cavity Method requires the calculation of a Room Cavity Ratio (RCR) followed by a lookup for Coefficient of Utilization (CU). This method was used for lighting layouts for fixtures using lamps but does not translate well when doing layouts with LED fixtures. While rendering programs using IES files can provide detailed layouts, there is an alternate method, working from first principles, to do easy LED layouts on the back of a napkin. Sri Rahm will present this method and invite a discussion.


Our speaker, Sri Rahm, M.S. (Physics), M.B.A., LC is a Senior Lighting Application Specialist and instructor at GE’s Lighting Institute at Nela Park, Cleveland, Ohio. He has worked in the Industry for over 35 years and served on several committees of the IES.


  • When: Thursday, May 30, 2019

  • Registration & lunch buffet: 11:30 a.m.

  • Program: 12 p.m.–1 p.m.

  • Sponsor: Current, by GE

  • Location: Hilton Garden Inn Downtown Cleveland
    1100 Carnegie Ave, Cleveland, Ohio 44113

  • Cost: $30

  • RSVP by: Wednesday, May 29


Pay by check or cash at the event, or by credit card using PayPal below.


IES May 2019


Mike Confer, Treasurer