CLD Lighting Design Codes, Standards & Regulations 2 — Questions and Answers
Question 1: Which ASHRAE/IES standard provides energy efficiency requirements for lighting in commercial buildings?
- ASHRAE 90.1 (Correct answer)
- ASHRAE 55
- ASHRAE 62.1
- ASHRAE 189.1
Correct answer: ASHRAE 90.1
ASHRAE 90.1 sets lighting power density limits and controls requirements for commercial buildings.
Question 2: Under ASHRAE 90.1, what is the primary metric used to measure a lighting system's energy efficiency compliance?
- Lighting Power Density (LPD) in W/ft² (Correct answer)
- Color Rendering Index (CRI)
- Efficacy in lumens per watt
- Illuminance in foot-candles
Correct answer: Lighting Power Density (LPD) in W/ft²
Lighting Power Density (LPD), expressed in watts per square foot, is the key compliance metric under ASHRAE 90.1.
Question 3: The IES RP-1 document specifically addresses lighting recommendations for which application?
- Office lighting (Correct answer)
- Healthcare facilities
- Sports venues
- Exterior roadways
Correct answer: Office lighting
IES RP-1 is the Recommended Practice for Office Lighting, providing illuminance targets and quality guidelines.
Question 4: Which section of the International Building Code (IBC) primarily governs means-of-egress lighting levels?
- Section 1008 (Correct answer)
- Section 1205
- Section 907
- Section 1104
Correct answer: Section 1008
IBC Section 1008 specifies minimum illuminance levels (1 fc average) for egress paths during normal and emergency conditions.
Question 5: When a jurisdiction adopts the 2021 IECC, which lighting control is typically required for all interior spaces greater than 5,000 ft²?
- Automatic shutoff controls (Correct answer)
- Dimming controls only
- Manual switching only
- Daylight harvesting sensors
Correct answer: Automatic shutoff controls
The 2021 IECC mandates automatic shutoff controls (occupancy or scheduling) for interior spaces exceeding 5,000 sq ft.
Question 6: Title 24, Part 6 is California's energy code equivalent to ASHRAE 90.1. What unique requirement does California Title 24 impose that ASHRAE 90.1 does not explicitly mandate?
- Multi-level lighting controls in most occupied spaces (Correct answer)
- Emergency lighting on battery backup
- Exit sign illumination levels
- Minimum CRI of 80 for all fixtures
Correct answer: Multi-level lighting controls in most occupied spaces
Title 24 Part 6 requires multi-level lighting controls allowing at least two levels of light output in most occupied spaces.
Question 7: According to the NEC Article 700, what minimum illuminance level must emergency egress lighting provide at the floor level?
- 1 foot-candle average with 0.1 fc minimum (Correct answer)
- 5 foot-candles average
- 10 foot-candles at any point
- 0.5 foot-candles average
Correct answer: 1 foot-candle average with 0.1 fc minimum
NEC Article 700 and NFPA 101 require egress lighting to maintain an average of 1 fc with no point below 0.1 fc.
CLD Lighting Design Codes, Standards & Regulations 2
Which ASHRAE/IES standard provides energy efficiency requirements for lighting in commercial buildings?