CLD Study Guide 2026
Everything you need to pass the CLD exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 CLD Exam Format at a Glance
📚 CLD Topics to Study (71)
✍️ Sample CLD Questions & Answers
1. What distinguishes 'ambient' lighting from 'task' lighting in a layered lighting design?
Ambient lighting establishes overall baseline illumination for a space, while task lighting supplements it with higher, directed light for work activities like reading or cooking.
2. What role does collaboration play in energy codes for CLD professionals?
Collaboration leverages diverse perspectives and combined expertise to achieve better outcomes than any individual could alone.
3. A project targets net-zero energy. What is the correct order of the energy hierarchy a designer should follow?
Best practice is to first reduce demand through efficiency, then optimize controls and systems, and finally generate on-site renewable energy to offset remaining loads.
4. What is 'phantom load' (also called standby power) in the context of lighting control devices?
Phantom or standby load is the power consumed by electronic devices (dimmers, drivers, sensors) while the connected luminaire is off, which adds up across large installations.
5. Which professional attribute is most valued in interior lighting within the CLD field?
Accountability and commitment to professional standards build trust and ensure consistent, high-quality practice.
6. The Dark Sky Association's five-zone system (E0–E4) is based on which primary environmental characteristic?
The IDA/IES Model Lighting Ordinance environmental zones E0–E4 are defined by the existing ambient brightness of the nighttime environment, from pristine dark sky (E0) to urban core (E4).