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About
Our Organization
About The IES
Diversity & Inclusion
Society Awards
Administration
IES Staff
IES Board
IES Committees
Information
Newsroom
Annual Report
Resources
Membership
Membership
Join
Sustaining Membership
Emerging Professionals
IES Committees
University Program
Grants & Scholarships
Section Directory
Section Resources
Global Access Affiliate Program
Volunteer Opportunities
Philantropic Donations
Events
Information
Events Home
Events Calendar
Sponsorship
Featured Events
IES25 The Lighting Conference
SALC 2025
Special Events
Lightfair 2025
Light for Life® Virtual Symposium
Illumination Awards & Gala
Research & Education
Research
About IES Research
Publications
FIRES
Past Projects
Education
eLearning Portal
Upcoming Webinars
Request IES CEU/AIA-LUs
LC Study Group
Education FAQs, Forms & Guidelines
Standards
Standards
Purchase Standards
Browse Library of Lighting Standards
Nomenclature & Definitions
Join a Technical Committee
Information
Standards Newsletter
IES Standards Process
Continuous Maintenance Form
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IES Standards Toolbox
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LD+A
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reciprocity
[12.11] [See
law of reciprocity (Bunsen-Roscoe law)
.]
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