CPII Code Requirements 3 — Questions and Answers
Question 1: According to the International Plumbing Code (IPC), what is the minimum slope required for horizontal drainage piping with a diameter of 3 inches or less?
- 1/16 inch per foot
- 1/8 inch per foot
- 1/4 inch per foot (Correct answer)
- 1/2 inch per foot
Correct answer: 1/4 inch per foot
The IPC requires horizontal drainage pipe 3 inches in diameter or less to slope at a minimum of 1/4 inch per foot (2%) to ensure proper flow.
Question 2: Under AASHTO LRFD Bridge Design Specifications, what minimum live load model must be used when designing public highway bridges?
- HL-67
- HL-93 (Correct answer)
- H-20
- HS-25
Correct answer: HL-93
AASHTO LRFD specifications require the HL-93 notional load model, which consists of a combination of a design truck or tandem plus a design lane load.
Question 3: A concrete sidewalk panel is observed with a vertical displacement of 3/4 inch between sections. Under ADA accessibility guidelines, this condition primarily represents a violation of which requirement?
- Cross slope maximum
- Running slope maximum
- Surface discontinuity limit (Correct answer)
- Width minimum
Correct answer: Surface discontinuity limit
ADA guidelines limit surface discontinuities (vertical changes in level) to 1/4 inch maximum, or 1/2 inch if beveled at 1:2 slope; 3/4 inch exceeds both thresholds.
Question 4: Which ASTM standard governs the specification for Portland cement used in public infrastructure concrete construction?
- ASTM C33
- ASTM C94
- ASTM C150 (Correct answer)
- ASTM C260
Correct answer: ASTM C150
ASTM C150 is the Standard Specification for Portland Cement, defining the eight types and their chemical and physical requirements.
Question 5: Under the Clean Water Act (CWA) Section 402, a construction site disturbing one or more acres must obtain which type of permit?
- Section 404 dredge-and-fill permit
- NPDES Construction General Permit (Correct answer)
- Section 401 water quality certification
- RCRA solid waste permit
Correct answer: NPDES Construction General Permit
EPA's NPDES Construction General Permit (CGP) under CWA Section 402 is required for stormwater discharges from construction sites disturbing one acre or more.
Question 6: When inspecting a newly installed sanitary sewer, the inspector requires a mandrel test. What is the primary defect this test is designed to detect?
- Pipe joint leakage
- Excessive deflection in flexible pipe (Correct answer)
- Pipe invert elevation errors
- Manhole frame settlement
Correct answer: Excessive deflection in flexible pipe
A mandrel (or go/no-go) test is pulled through flexible pipe to verify that deflection (out-of-round deformation) does not exceed the allowable limit, typically 5% of the internal diameter.
Question 7: According to OSHA 1926.652, what classification applies to a trench excavation in Type C soil with vertical walls at a depth of 6 feet?
- No protective system required
- Slope at 3/4:1 (H:V)
- Slope at 1.5:1 (H:V) or use shoring/shielding (Correct answer)
- Slope at 1:1 (H:V)
Correct answer: Slope at 1.5:1 (H:V) or use shoring/shielding
Type C soil is the least stable classification; OSHA requires a 1.5:1 horizontal-to-vertical slope or an equivalent protective system for excavations deeper than 5 feet.
CPII Code Requirements 3
According to the International Plumbing Code (IPC), what is the minimum slope required for horizontal drainage piping with a diameter of 3 inches or less?