NABCEP Safety Practices 4 — Questions and Answers
Question 1: A solar crew chief is conducting a Job Hazard Analysis (JHA) before a roof installation. Which step comes FIRST in the JHA process?
- Select the PPE to be worn
- Break the job into basic steps (Correct answer)
- Identify the hazards for each step
- Determine preventive measures
Correct answer: Break the job into basic steps
A JHA begins by breaking the task into sequential steps before hazards can be identified and controls assigned.
Question 2: During a hot-work permit process for a rooftop installation requiring grinder use, which condition requires an immediate work stoppage?
- Wind speed exceeds 5 mph
- A fire watch is not posted within 35 feet of the work (Correct answer)
- The grinder blade is less than 6 months old
- Ambient temperature is above 90°F
Correct answer: A fire watch is not posted within 35 feet of the work
NFPA 51B and site hot-work permits require a fire watch within 35 feet of hot work; absence of a fire watch is grounds for immediate stoppage.
Question 3: What is the correct sequence for donning Arc Flash PPE before working on an energized PV combiner box?
- Gloves → arc-rated clothing → face shield → hearing protection
- Arc-rated clothing → face shield/hood → rubber gloves with leather protectors → other PPE (Correct answer)
- Face shield → clothing → gloves → hearing protection
- Hearing protection → gloves → clothing → face shield
Correct answer: Arc-rated clothing → face shield/hood → rubber gloves with leather protectors → other PPE
Arc-rated clothing is donned first to establish the base layer, followed by head/face protection, then rubber insulating gloves with leather protectors, then ancillary PPE.
Question 4: A solar installer in Arizona is working outdoors in July. OSHA's Heat Illness Prevention guidance requires a rest break in the shade when the heat index exceeds which threshold?
- 80°F
- 91°F
- 103°F (Correct answer)
- 115°F
Correct answer: 103°F
OSHA's heat illness prevention guidance recommends mandatory rest breaks and enhanced controls when the heat index reaches 103°F (39°C) or above.
Question 5: Which document must be available on-site at all times during a construction phase PV installation to comply with OSHA Hazard Communication requirements?
- The manufacturer's warranty cards for all equipment
- Safety Data Sheets (SDS) for all hazardous chemicals on site (Correct answer)
- The electrical engineer's stamped drawings
- The utility interconnection agreement
Correct answer: Safety Data Sheets (SDS) for all hazardous chemicals on site
OSHA 29 CFR 1910.1200 (HazCom) requires SDS for all hazardous substances to be readily accessible to workers during each work shift.
Question 6: A module develops a hot spot during commissioning and its surface temperature reads 185°F. What is the FIRST action the technician should take?
- Immediately cut the string wires to isolate the module
- De-energize the string using the combiner disconnect, then assess the module (Correct answer)
- Apply water to cool the module surface
- Continue commissioning and flag the module for warranty replacement
Correct answer: De-energize the string using the combiner disconnect, then assess the module
The first step is controlled de-energization of the affected string via the combiner disconnect before physically handling or assessing the overheated module.
Question 7: Under NEC 690.56, what is required at a building with a PV system to enable first responders to quickly disconnect power?
- A red warning label on the main panel only
- A building disconnecting means accessible from the outside or identified for emergency responder use (Correct answer)
- An automatic shutdown relay installed in the main panel
- A posted phone number for the utility emergency line
Correct answer: A building disconnecting means accessible from the outside or identified for emergency responder use
NEC 690.56 requires a building disconnecting means for PV systems that is readily accessible and identified for use by emergency responders.
NABCEP Safety Practices 4
A solar crew chief is conducting a Job Hazard Analysis (JHA) before a roof installation.
Which step comes FIRST in the JHA process?