NABCEP Building and Fire Codes 4 — Questions and Answers
Question 1: The IFC requires a clear perimeter pathway around the roof edge of a large flat commercial building with a PV system. What is the minimum width of this perimeter pathway?
- 18 inches
- 6 feet
- 4 feet (Correct answer)
- 36 inches
Correct answer: 4 feet
The IFC requires a minimum 4-foot-wide perimeter pathway around the roof edge of commercial buildings to allow firefighter movement and ventilation operations.
Question 2: Which NFPA standard specifically covers the installation of stationary energy storage systems including battery-based PV storage in buildings?
- NFPA 70 (NEC)
- NFPA 855 (Correct answer)
- NFPA 13
- NFPA 72
Correct answer: NFPA 855
NFPA 855, Standard for the Installation of Stationary Energy Storage Systems, specifically governs battery and other ESS installations in and around buildings.
Question 3: Under the IFC, interior-mounted inverters must be separated from Group H occupancy areas by a fire barrier with a minimum fire-resistance rating of how many hours?
- 1 hour
- 2 hours (Correct answer)
- 3 hours
- 4 hours
Correct answer: 2 hours
The IFC requires a minimum 2-hour fire barrier between inverter rooms and adjacent Group H (high-hazard) occupancy areas to contain potential electrical fires.
Question 4: When ground-mounted PV arrays are classified as a structure under the IBC, which wind speed map must be used to determine design wind pressure?
- ASCE 7 Risk Category I map for residential use
- The local jurisdiction's adopted wind speed map per the IBC (Correct answer)
- ANSI/AISC 360 wind speed tables
- OSHA wind speed criteria for temporary structures
Correct answer: The local jurisdiction's adopted wind speed map per the IBC
The IBC requires use of the locally adopted wind speed map from ASCE 7, which varies by Risk Category and geographic location.
Question 5: Which NEC requirement ensures that a PV system's DC arc-fault protection disconnects the faulted source circuit under the 2020 NEC?
- NEC 690.9 (Overcurrent Protection)
- NEC 690.11 (Arc-Fault Circuit Protection) (Correct answer)
- NEC 690.12 (Rapid Shutdown)
- NEC 690.35 (Ungrounded PV Systems)
Correct answer: NEC 690.11 (Arc-Fault Circuit Protection)
NEC 690.11 requires listed DC arc-fault circuit interrupters (AFCIs) on PV systems with DC source circuits operating above 80V to detect and interrupt arcing faults.
Question 6: What is the maximum allowed height of a ground-mounted PV array before it triggers a 'structure' permit requiring engineered drawings under most U.S. building codes?
- 8 feet above grade
- Determined by the AHJ — no universal federal threshold (Correct answer)
- 12 feet above grade
- 6 feet above grade
Correct answer: Determined by the AHJ — no universal federal threshold
There is no single federal threshold; the height at which ground-mounted PV arrays require engineered structural drawings is determined by each AHJ under their adopted building code.
Question 7: Under the IFC, which condition requires a fire sprinkler system under a rooftop PV array on a new commercial building?
- Array area exceeds 6,000 square feet or covers more than 33% of roof area (Correct answer)
- The building is fully sprinklered and array is over 2,500 sq ft
- Arrays at height above 30 feet above grade
- Any array on a Group B occupancy over 3 stories
Correct answer: Array area exceeds 6,000 square feet or covers more than 33% of roof area
The IFC requires sprinkler protection under rooftop PV arrays when the array exceeds 6,000 square feet or covers more than one-third of the roof area.
NABCEP Building and Fire Codes 4
The IFC requires a clear perimeter pathway around the roof edge of a large flat commercial building with a PV system.
What is the minimum width of this perimeter pathway?