Inspection, Testing, and Plan Review
What Inspectors Verify
Inspection questions test the sequence and content of inspections: underground rough-in, rough-in, final, and special inspections. Know what must be visible before concealment and what tests are required for water supply, drainage, and gas piping.
Testing Requirements
Water supply systems are tested under pressure for a specified duration with no drop in pressure beyond allowance. Drainage systems are tested with water or air; know the difference between a hydrostatic test and a smoke or air test, and when each is acceptable. Traps include testing only part of a system, failing to test before concealment, and confusing a pressure test with a flow test.
Plan Review
Plan review checks completeness: fixture-unit calculations, riser diagrams, venting layout, and equipment schedules. Reviewers verify that submitted plans show the size and location of all piping and that calculations match the drawings. A common trap is a plan that shows a fixture without a vent or a drain without a slope.
Worked Example
A contractor installs a building drain and covers it before inspection. The correct answer is that the work must be exposed for inspection; the inspector cannot accept concealed work based on a photograph unless the code or AHJ permits it.