CLD Cheat Sheet 2026

The 30 highest-yield CLD facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which professional attribute is most valued in lighting fundamentals within the CLD field? → Accountability and commitment to standards
2. Which approach best demonstrates mastery of controls and dimming in CLD practice? → Applying principles to novel situations with sound judgment
3. Luminous intensity is measured in which unit? → Candela
4. What is the best practice for maintaining daylighting design performance over time? → Implement scheduled preventive maintenance
5. What is the primary function of a 0–10 V dimming signal? → Low‑voltage DC dimming control
6. Under NFPA 70 (National Electrical Code), outdoor luminaires installed in wet locations must be listed and labeled for: → 'Wet location' use
7. When planning a project in Certified Lighting Designer, which element should be established FIRST? → Clear objectives, scope, and success criteria
8. Which approach best demonstrates mastery of energy codes in CLD practice? → Applying principles to novel situations with sound judgment
9. A restaurant designer wants to create a candlelight effect using electric lighting. Which combination of luminaire characteristics best achieves this? → Low-lumen 1800K–2200K sources with warm-dim capability
10. A hospital corridor is lit to 30 fc for normal operation and automatically steps down to 5 fc when unoccupied at night. This strategy is best described as: → Bi-level switching
11. Which professional attribute is most valued in energy codes within the CLD field? → Accountability and commitment to standards
12. Which lighting technique is commonly used to highlight architectural features? → Accent lighting
13. Which IES light trespass standard defines the maximum allowable vertical illuminance at a neighboring property line? → IES G-1-03
14. For a high-mast lighting installation (pole height ≥20m), which factor most significantly increases maintenance costs compared to standard-height pole lighting? → Requirement for bucket-truck or climbing access to service the luminaire head
15. Typical North‑American branch circuit voltage for lighting is: → 120 V
16. What is the value of continuing education in interior lighting for CLD professionals? → It keeps professionals current with evolving standards and practices
17. In outdoor sports lighting design, the term 'uniformity ratio' most commonly refers to which measurement? → Average to minimum illuminance (Eavg/Emin)
18. What is the MOST effective way for new CLD professionals to build competency in their field? → Combining formal education, mentored practice, and ongoing professional development
19. What is the primary consideration when implementing changes to daylighting design? → Impact assessment and change management
20. How should a CLD professional manager address underperformance within their team? → Provide timely, specific feedback with support and a clear improvement plan
21. Circadian‑centric tunable white systems: → Shift CCT through day
22. Which mounting configuration is typically used for sports field floodlights to achieve the highest uniformity across a rectangular playing field? → Four corner poles with symmetrical aiming
23. What is the most important professional competency for CLD certification in sustainability? → Deep knowledge combined with practical application skills
24. What does a lighting control system allow users to do? → Adjust light levels and automate lighting schedules
25. In CLD practice, what is the best approach to quality improvement in interior lighting? → Use data-driven methods with measurable outcomes
26. Which approach best reduces 'spill light' onto an adjacent residential property from a commercial parking lot? → Selecting luminaires with asymmetric Type II or III distributions aimed inward
27. NFPA 101 requires minimum _____ along egress path. → 1 fc
28. A specification requires luminaires with a minimum efficacy of 100 lumens per watt. Which technology is most likely to achieve this threshold? → LED with high-efficiency driver
29. DALI enables luminaires to: → Communicate digitally with addresses
30. In roadway lighting design, 'veiling luminance' primarily affects driver vision by: → Reducing perceived contrast of objects on the road ahead