Inspection Procedures, Safety, and Reporting
What this domain tests
This domain tests a repeatable inspection sequence, safe handling of tank lids and gases, and reports that separate observation from opinion.
Core rules and concepts
- Review records and interview the owner before arriving: age, pump dates, repairs, backups, and number of occupants.
- Locate the tank using as-built drawings, probing, or a tracer. Confirm lid condition and access.
- Treat every tank as a confined space. Never enter a septic tank. Gases include hydrogen sulfide, methane, and carbon monoxide; oxygen can be deficient. Use a gas meter when needed, keep traffic away from lids, and do not smoke.
- Measure sludge depth with a sludge judge, scum thickness, and liquid level relative to the outlet invert.
- Inspect baffles, effluent filter, distribution box, pump floats, alarm, and drainfield. Run water and, where appropriate, a dye test.
- Report what was accessible, what was not, and the limitations. Photograph defects with a scale and describe their location.
Worked example
The tank liquid level is 3 inches above the outlet invert, and the drainfield is soggy. The reasoning: a field that cannot accept effluent backs water up into the tank. The tank may also be overdue for pumping, but the high level at the outlet points to downstream restriction. Report both possibilities and recommend evaluation before pumping alone is offered as a cure.
Traps that cost marks
Do not open a lid without fall protection and gas awareness. Do not rely on a dye test as the only evidence of failure. Do not call a hairline crack a structural failure without context. Do not omit inaccessible components from the report.