CDT Blueprint Reading & Specifications 3 — Questions and Answers
Question 1: In blueprint reading, what does a centerline symbol (CL or ℄) signify?
- The boundary of a property line
- The axis of symmetry or center of a feature such as a hole or shaft (Correct answer)
- The edge of a cutting plane
- A hidden structural element
Correct answer: The axis of symmetry or center of a feature such as a hole or shaft
Centerlines mark the axis of symmetric features and are used to locate holes, shafts, and similar elements.
Question 2: Which specification writing method describes the desired result or performance level without specifying a particular product?
- Prescriptive specification
- Performance specification (Correct answer)
- Proprietary specification
- Reference standard specification
Correct answer: Performance specification
Performance specifications state what the finished product must achieve, leaving the means to the contractor.
Question 3: On a structural drawing, what does 'W12×53' describe?
- A wide-flange steel beam, 12 inches nominal depth, weighing 53 pounds per linear foot (Correct answer)
- A wood member 12 inches wide by 53 inches long
- A wall section 12 feet high with 53 studs
- A welded connection with 12 passes and 53 ksi strength
Correct answer: A wide-flange steel beam, 12 inches nominal depth, weighing 53 pounds per linear foot
The 'W' designation denotes a wide-flange shape; the first number is nominal depth in inches and the second is weight per foot.
Question 4: What does the symbol 'Ø' preceding a dimension number indicate on a mechanical drawing?
- The dimension is a radius measurement
- The feature is a diameter (Correct answer)
- The tolerance is zero
- The feature is optional
Correct answer: The feature is a diameter
The Ø symbol indicates that the dimension refers to the diameter of a circular feature.
Question 5: In the CSI three-part specification format, Part 2 covers:
- General administrative and procedural requirements
- Products, materials, and their standards (Correct answer)
- Execution, installation, and workmanship methods
- Quality assurance and submittals
Correct answer: Products, materials, and their standards
Part 2 (Products) specifies the materials, components, and manufactured items to be used.
Question 6: On a site plan, contour lines that are close together indicate:
- Flat, level terrain
- Steep slope or rapid elevation change (Correct answer)
- Underground utilities
- Property boundaries
Correct answer: Steep slope or rapid elevation change
Closely spaced contour lines mean elevation changes rapidly over a short horizontal distance, indicating steep terrain.
Question 7: What is the purpose of a 'break line' on a technical drawing?
- To indicate where a weld seam occurs
- To show that a long or repetitive object has been shortened to fit the drawing sheet (Correct answer)
- To mark demolition boundaries
- To indicate a hidden feature
Correct answer: To show that a long or repetitive object has been shortened to fit the drawing sheet
Break lines allow long uniform objects to be represented at a larger scale by omitting the middle section.
CDT Blueprint Reading & Specifications 3
In blueprint reading, what does a centerline symbol (CL or ℄) signify?