InterNACHI Pool & Spa Inspector flashcards
InterNACHI Pool & Spa Inspector · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Turnover time
- Total pool volume in gallons divided by the system flow rate in gallons per minute gives minutes per turnover; residential pools are commonly designed for about six to eight hours.
- Anti-entrapment drain cover
- A cover over a submerged suction outlet that must be rated for the pump's flow and marked with a VGB compliance label; a missing or broken cover is an immediate hazard.
- Single-blockable outlet
- A suction outlet that one person's body can fully cover, cutting off flow and creating entrapment force; it must be paired with a second outlet or a vented equalizer line.
- Skimmer equalizer line
- A secondary suction opening below the skimmer that draws water if the skimmer mouth is blocked, preventing the pump from pulling a body or limb against the skimmer throat.
- Filter pressure rise
- A rise of roughly eight to ten psi above the clean filter baseline indicates loading; backwash or clean the filter and note the clean baseline for future comparison.
- Barrier height rule
- Pool barriers must be at least four feet high with no footholds, and gates must be self-closing, self-latching, and open outward with the latch high out of a child's reach.
- Equipotential bonding
- A grid of conductive material connecting pool water, deck, and metal equipment so voltage differences cannot occur; a missing bond wire at the pump is a reportable defect.
- GFCI protection
- Ground-fault circuit interrupter protection is required for pool pumps, lights, and receptacles near water; test the device and report any circuit lacking protection.
- Free chlorine range
- Free chlorine is typically maintained at one to three ppm in a pool; cyanuric acid stabilizes it, and higher CYA levels require correspondingly higher free chlorine to stay effective.
- pH range
- Pool and spa pH is typically kept between 7.2 and 7.8; low pH corrodes metal and etches plaster, while high pH reduces chlorine kill power and causes scale.
- Total alkalinity
- Total alkalinity of roughly 80 to 120 ppm buffers pH against swings; low alkalinity lets pH bounce, and high alkalinity makes pH hard to lower.
- Calcium hardness
- Calcium hardness of about 200 to 400 ppm protects plaster from dissolving; low hardness etches surfaces and high hardness deposits scale on tile and in the heater.
- Cyanuric acid
- Cyanuric acid protects chlorine from sunlight but reduces its effectiveness when too high; elevated levels are common in outdoor pools and call for partial draining.
- Combined chloramines
- Combined chlorine above roughly 0.5 ppm produces the characteristic chlorine odor and eye irritation, indicating the need to shock or partially drain the pool.
- Saturation index
- The Langelier saturation index combines pH, temperature, calcium hardness, total alkalinity, and dissolved solids; a negative value etches plaster and a positive value scales it.
- Spa maximum temperature
- The maximum safe spa water temperature is 104 degrees Fahrenheit; hotter water raises the risk of scald, heat exhaustion, and cardiac stress, especially for children and pregnant users.
- Spa high-limit switch
- A safety device that cuts power to the spa heater if water temperature exceeds a set limit; a failed high-limit switch is a scald and fire hazard.
- Heater pressure switch
- A switch that proves water flow before the heater fires; a failed switch can allow the heater to run dry, damaging the heat exchanger and creating a fire risk.
- Sediment trap
- A downward leg on the gas supply piping near the heater that catches debris before it reaches the burner; its absence is a reportable gas-piping defect.
- Autofill air gap
- An autofill line connected to potable water needs an air gap or approved backflow preventer so pool water cannot siphon into the drinking water supply.
- Deck slope
- Pool decks should slope away from the pool so splash and rain drain away; ponding or slope toward the pool indicates a drainage defect worth reporting.
- Coping joint
- The joint between coping and deck that allows movement; a failed or missing joint creates a trip hazard and lets water into the pool structure.
- Safety equipment
- A reach pole and a ring buoy should be visible and accessible at the pool; missing safety equipment is a condition to note in the report.
- Overhead conductor clearance
- Service conductors must maintain required horizontal and vertical clearance from the pool water surface; insufficient clearance is a shock hazard to anyone using a pole.
- Visible algae
- Green, yellow, or black growth on pool surfaces indicates inadequate sanitizer or circulation; report it as an observed condition rather than a chemical conclusion.
- Scale line
- A white crusty line at the waterline signals high calcium hardness or high pH; it is an observable clue to water balance history and plaster condition.
- Plaster etching
- Rough, chalky, or pitted plaster indicates aggressive water with a negative saturation index; the condition is visible and should be described in the report.
- Main drain grate
- The grate over the main drain must be intact, secured, and rated for flow; a loose or missing grate exposes a large suction opening and is an entrapment hazard.
- Air blower
- A spa air blower feeds venturi jets and raises pH over time by driving off carbon dioxide; note blower condition and any water in the air line.
- Check valve at heater
- A check valve prevents hot water from backflowing into spa plumbing when the system shuts down; its absence can damage PVC lines and the heater.
- Flow meter
- A device on the return line that shows actual flow in gallons per minute; combined with volume it confirms whether turnover meets the design intent.
- Pool volume formula
- For a rectangular pool, volume in gallons equals length times width times average depth times 7.48; average depth is the mean of shallow and deep ends.