ASSE 5110 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Backsiphonage

Reverse flow caused by a negative or sub-atmospheric pressure in the supply piping; atmospheric pressure pushes downstream liquid back into the potable system.

Backpressure

Reverse flow that occurs when downstream pressure, created by a pump, boiler, elevation, or compressed gas, exceeds the pressure in the potable supply line.

Cross-connection

Any actual or potential link between a potable water system and a source of contamination or pollution that could allow unwanted substances to enter drinking water.

Elevation to pressure conversion

One foot of water column equals 0.433 psi, and one psi equals 2.31 feet of head; used to compute supply, backpressure, and siphon break elevations.

Critical level

The flood level rim of the lowest fixture served, or the marked critical level of an assembly, that must remain above every downstream opening or outlet.

Safe Drinking Water Act

Federal law authorizing EPA drinking water standards; states with primacy then adopt cross-connection control rules, frequently delegating enforcement to local health agencies.

ASSE 1013

Product standard covering reduced pressure principle backflow prevention assemblies, the testable device required for high-hazard protection against backpressure and backsiphonage.

ASSE 1015

Product standard for pressure vacuum breaker assemblies: testable devices giving backsiphonage-only protection through a loaded check valve and an air inlet.

Containment versus isolation

Containment protects the public main at the service connection; isolation protects individual fixtures or internal zones. Ordinances generally require containment and apply isolation to high-hazard internal uses.

CSA B64.10

Canadian standard for selection and installation of backflow preventers; its companion document B64.10.1 covers field testing, maintenance, and tester requirements.

Air gap

Physical separation between a potable outlet and the flood level rim; the gap must be at least one inch or twice the pipe diameter, whichever is larger.

Atmospheric vacuum breaker

Non-testable device whose air inlet opens at zero flow; it allows no downstream shutoff valve, no continuous pressure, and must sit above all downstream outlets.

Pressure vacuum breaker

Testable device with a spring-loaded check and air inlet; it needs at least twelve inches of elevation above the highest downstream outlet and cannot be used under backpressure.

Reduced pressure principle assembly

Testable assembly of two check valves and a differential relief valve that protects against both backpressure and backsiphonage on high-hazard connections.

Double check assembly

Testable assembly of two independent check valves providing low-hazard protection only; it has no relief valve and cannot discharge water to relieve thermal expansion.

Detector assembly

Reduced pressure or double check assembly fitted with a metered bypass that reveals leakage or unauthorized water use on fire sprinkler and other normally closed lines.

Test cock numbering

Reduced pressure assemblies have four test cocks: upstream of check one, between the checks, downstream of check two, and in the relief valve zone.

RP relief opening point

The relief valve must begin to open when the differential across check one falls to 2.0 psi or less; a lower opening point is a failing result.

Check one static drop

With the downstream side bled to atmosphere, check one must hold at least five psi of static differential; a lower reading indicates leakage past the check.

Second check backpressure test

Using test cocks three and four, check two must hold one psi of backpressure without leakage; any drip or gauge fall means failure.

PVB air inlet test

The air inlet must open at a differential of one psi or less, and the check valve must hold one psi of backpressure, or the assembly fails.

Test gauge calibration

Differential gauges used for assembly testing must be calibrated at least annually by a qualified laboratory, with the current certificate carried in the test kit.

RP relief continuous discharge

Steady discharge with no downstream flow means check one is fouled or damaged, or inlet pressure has been lost; inspect and rebuild check one first.

RP relief intermittent discharge

Short bursts of relief discharge usually come from thermal expansion, water hammer, or supply pressure swings rather than a failed check valve.

Check valve chatter

Rapid fluttering indicates a worn disc, damaged seat, broken spring, or flow below the manufacturer's minimum; disassemble and install the OEM repair kit.

Approved elastomer lubricant

Use only manufacturer-approved silicone or water-based lubricant on rubber seats and O-rings; petroleum-based grease swells and degrades EPDM and Buna-N compounds.

Upstream strainer requirement

Most reduced pressure assemblies require a strainer ahead of the inlet to keep scale and debris out of check one and the relief valve sensing passage.

Test report contents

Reports must list make, model, size, serial number, location, hazard class, each gauge reading, tester name and certification number, date, and gauge calibration information.

Assembly test tag

A durable tag fixed to the assembly records the test date, tester identity, results, and next test due date so inspectors can verify status on site.

Record retention period

Jurisdictions commonly require test reports and repair records be kept three to five years; the local ordinance sets the exact period and storage format.

Containment program inventory

A current list of every assembly with its hazard level and test due date underpins reminder mailings, compliance percentages, and inspection workload planning.

Noncompliance escalation

The usual enforcement sequence is reminder, notice of violation, short re-test deadline, and finally water service termination or a penalty under the local ordinance.