OBC Plumbing House study plan

Define at least 60 core plumbing terms (trap, stack, vent, fixture unit, developed length, grade, invert, crown, weir, air gap) in your own words and group them by system.

Decode common plumbing symbols and abbreviations used on isometric and plan drawings, including waste, vent, water, and gas line symbology.

Sketch a simple DWV isometric from a written description showing soil stack, branch wastes, traps, and vents.

Explain the difference between a soil stack, waste stack, vent stack, and stack vent without notes.

Convert fixture units to drainage fixture unit loads for a small bathroom group using a provided table you copy out yourself.

Trace the path of a vent system from fixture trap to termination and identify each vent type (individual, common, wet, circuit, island, relief).

Calculate trap arm length limits and slope requirements for common fixture sizes.

Identify the conditions that require a vent and the conditions that permit common venting.

Describe how a trap seal is protected and list the causes of trap seal loss.

Size a simple branch drain and vent using fixture-unit tables you build yourself from study notes.

Lay out a complete DWV system for a two-bath house on paper, including stack, building drain, and vent termination above roof.

Explain building drain versus building sewer, and where the property line changes code jurisdiction.

Describe water supply components: service line, meter, main, riser, branch, and fixture stop.

Compute minimum pipe sizing for a supply branch given fixture values and developed length.

Explain the purpose of a water hammer arrestor, pressure-reducing valve, and backflow preventer.

Describe potable water protection requirements, including air gaps, vacuum breakers, and cross-connection control.

Explain water temperature limits and scald protection at fixtures.

Identify the sanitary requirements for fixture clearance, lighting, and ventilation in bathrooms.

List the health-related reasons behind trap seal requirements and prohibited connections.

Explain how backflow and cross-connection hazards are tested and corrected.

Classify fixtures by type and state the minimum fixture requirements for a single-family dwelling.

Explain fixture fitting requirements including faucets, flush valves, and trap standards.

Describe the permit process from application to final inspection and the role of each inspection stage.

List the inspections typically required (rough-in, underground, final) and what each verifies.

Explain who may perform plumbing work and when a permit is exempt.

Match common pipe materials (copper, PEX, PVC, ABS, cast iron, galvanized steel) to their approved uses and restrictions.

Describe approved joining methods for each material and where solvent cement or solder is prohibited.

Explain storm drainage design basics: roof drains, leaders, sizing by rainfall, and secondary drainage.

Identify special waste systems such as grease interceptors, chemical waste, and acid-neutralizing systems.

Explain the difference between combined and separate storm and sanitary systems.

Describe the basic components of a residential fire sprinkler system and how it ties to the domestic water supply.

Explain standpipe, riser, and sprinkler head spacing concepts at a general level.

Identify coordination points between plumbing and structural, electrical, and HVAC trades (sleeves, chases, clearances).

Explain penetration and firestopping requirements where pipes pass through rated assemblies.

Describe how plumbing rough-in must coordinate with framing and foundation stages.

Complete a 100-question timed practice exam across all domains and score each domain separately.

Re-study any domain scoring below 75% and rewrite your weak-area notes.

Recite the top 40 terms and the ten most common code requirements from memory.

Redo two full sizing and layout problems under time pressure.

Build a one-page final review sheet of numbers, limits, and definitions.