CAT Blueprint Reading & Interpretation 3 — Questions and Answers
Question 1: A blueprint legend shows a half-filled circle symbol. According to NFPA 72 conventions, this typically represents a:
- Heat detector
- Combination smoke/heat detector (Correct answer)
- Manual pull station
- Duct smoke detector
Correct answer: Combination smoke/heat detector
A half-filled circle is commonly used to denote a combination smoke and heat detector on NFPA 72 compliant fire alarm drawings.
Question 2: What is the purpose of a 'detail' drawing referenced on a fire alarm plan?
- To show the overall building floor plan at reduced scale
- To provide enlarged views of complex or critical installation areas (Correct answer)
- To list all equipment quantities for the project
- To show the electrical panel schedule
Correct answer: To provide enlarged views of complex or critical installation areas
Detail drawings zoom in on specific areas to clarify complex installations that cannot be clearly shown at the standard plan scale.
Question 3: On a fire alarm blueprint, a solid triangle symbol pointing upward most commonly represents:
- A horn/strobe notification appliance
- A manual pull station (Correct answer)
- An end-of-line resistor location
- A fire alarm control panel
Correct answer: A manual pull station
A solid triangle or arrow-shaped symbol pointing upward is the NFPA 72 standard symbol for a manual pull station.
Question 4: Which document in a set of construction drawings would specify the wire type and insulation rating for fire alarm circuits?
- Architectural floor plans
- Electrical specifications (Division 28) (Correct answer)
- Structural drawings
- Civil site plan
Correct answer: Electrical specifications (Division 28)
Fire alarm wiring specifications, including conductor type and insulation rating, are found in Division 28 (Electronic Safety and Security) of the project specifications.
Question 5: A fire alarm drawing note states 'VFY W/AHJ'. What does this instruction require the technician to do?
- Verify wire size with the electrical inspector
- Verify the requirement with the Authority Having Jurisdiction (Correct answer)
- Verify voltage with an approved hand-held junction meter
- Verify the installation with a licensed alarm holder jointly
Correct answer: Verify the requirement with the Authority Having Jurisdiction
AHJ stands for Authority Having Jurisdiction; this note instructs the installer to confirm the requirement with that governing body before proceeding.
Question 6: On a fire alarm site plan, what is the PRIMARY purpose of showing the property boundary and building footprint together?
- To calculate the total number of devices needed
- To determine setback distances and locate outdoor notification appliances or control panel exits (Correct answer)
- To identify interior room finishes
- To show the routing of underground electrical feeders only
Correct answer: To determine setback distances and locate outdoor notification appliances or control panel exits
Combining the property boundary and footprint helps installers locate outdoor devices and building entry/exit points relative to code-required setbacks.
Question 7: Which view would BEST show the mounting height of a horn/strobe on an exterior wall?
- Floor plan
- Riser diagram
- Exterior elevation drawing (Correct answer)
- Site utility plan
Correct answer: Exterior elevation drawing
An exterior elevation drawing shows the wall face with height dimensions, making it ideal for verifying device mounting heights on exterior surfaces.
CAT Blueprint Reading & Interpretation 3
A blueprint legend shows a half-filled circle symbol.
According to NFPA 72 conventions, this typically represents a: