6.4 Non-Testable Devices Testers Must Recognize
Key Takeaways
- Non-testable means no USC-style DP field test with shutoffs and test cocks—not that protection is optional
- Air gaps provide ultimate protection by physical separation and are verified by inspection, not gauge tests
- ASSE 1001 AVBs protect against backsiphonage only and are not for continuous-pressure service
- Hose connection devices (1011/1052) and dual checks (1024) are common non-testable products distinct from 1015/1013 assemblies
- Memorize device numbers: 1001, 1011, 1012, 1013, 1015, 1020, 1024, 1047, 1048, 1052, 1056
Quick Answer
Not every cross-connection control product is a testable assembly with shutoffs and test cocks. Non-testable devices—including the air gap, atmospheric vacuum breaker (ASSE 1001), hose connection vacuum breakers (ASSE 1011 / 1052), dual checks (ASSE 1024), and related specialty products—still appear everywhere in the field. ASSE 5110 testers must recognize them, know what protection class they offer, and understand why “non-testable” does not mean “not required” or “not important.” You generally do not perform a USC-style differential-pressure field test on them the way you do on 1013, 1015, 1020, and 1056. You do report obvious defects, wrong applications, and missing protection when your role and local program require it. Master the device number recognition table early; written exams love number-to-name matching.
Testable Assemblies vs Non-Testable Devices
| Category | Typical features | ASSE 5110 practical focus | Examples |
|---|---|---|---|
| Testable assemblies | Inlet/outlet shutoffs, test cocks, field-testable internals | Yes—annual DP gauge procedures | 1013 RP, 1015 DC, 1020 PVB, 1056 SVB; also 1047/1048 detectors |
| Non-testable devices | Often no test cocks; limited or no shutoff package for gauge tests | Recognize and apply selection rules; do not “field test” like 1013 | 1001 AVB, 1011/1052 hose bibb VB, 1024 dual check, air gaps |
| Method (air gap) | Physical separation—no mechanical “pass/fail” gauge test | Measure/verify separation; ultimate protection | True air gap |
“Non-testable” is a testing-method label, not a permission to omit protection. Plumbing codes and purveyor rules still require correct devices at countless fixtures.
Air Gap — The Ultimate Protection
An air gap is a vertical physical separation between the potable outlet and the flood-level rim of the receiving fixture or vessel. With a proper gap, backsiphonage cannot bridge the open air space, and backpressure from the receiving vessel cannot push into the outlet if the outlet is truly unconnected and above the flood rim.
Why programs call it ultimate protection:
- No springs to fatigue, no seats to foul in the same way as mechanical checks.
- Visible and inspectable.
- Accepted for severe hazards when correctly installed (with the practical downside that it is not a pressurized “inline” connection).
Tester recognition tasks:
- Confirm the gap is unobstructed (no hoses jammed down into sinks, no added tubes defeating the gap).
- Know that mechanical assemblies are used when a pressurized connection is required; air gaps are not always operationally practical, but they set the protection benchmark.
Air gaps are not “field-tested” with a three-valve gauge. They are verified by inspection and measurement against code minimums (often expressed as a multiple of supply opening diameter, with absolute minimums—memorize your local code figures for field work; exams emphasize the concept of physical separation).
Atmospheric Vacuum Breaker — ASSE 1001
The AVB (ASSE 1001) is the classic non-continuous-pressure vacuum breaker:
| Attribute | AVB (1001) typical rules |
|---|---|
| Protection | Backsiphonage |
| Backpressure | No |
| Continuous pressure | No (not for continuous pressure service) |
| Test cocks | Usually none — non-testable device class |
| Common uses | Flushometer supplies, certain process sinks, fixture protection where flow is intermittent |
How it works (concept): during flow, the disc/float lifts and seals the air inlet; when flow stops, the air inlet opens to atmosphere so a siphon cannot form. Because it is not built as a continuous-pressure, shutoff-and-test-cock assembly, it is not interchangeable with a PVB (1020).
High-yield contrast:
- Valve left under pressure for long periods downstream of a shutoff that stays open → AVB misapplied; need PVB/SVB or RP/DC as appropriate.
- Simple fixture with intermittent use and correct elevation → AVB may be exactly right.
Hose Connection Vacuum Breakers — ASSE 1011 and 1052
Hose bibbs and sill cocks are notorious cross-connections: a garden hose in a pesticide sprayer, a sink, a pool, or a blocked drain creates classic backsiphonage (and sometimes backpressure if a nozzle is pressurized).
| Standard | Device idea | Field notes |
|---|---|---|
| ASSE 1011 | Hose connection vacuum breaker | Common screw-on or integral hose-bibb protection; backsiphonage-focused; typically non-testable |
| ASSE 1052 | Hose connection backflow preventer / dual check with atmospheric vent (hose connection style—know the 1052 label on exams) | Often provides additional features vs basic 1011 (such as better resistance to backpressure conditions on hose connections per product listing—follow listing and local approval); still generally not handled like a full 1013 field test |
Tester recognition:
- Look for devices on hose threads.
- Note damage, missing breakers, or hoses permanently tied that defeat protection.
- Understand these are point-of-use devices, not containment RPs at the meter.
You will not run a multi-step USC RP procedure on a $15 hose bibb vacuum breaker. You will know they exist and what hazard they address.
Dual Check — ASSE 1024
ASSE 1024 dual check valves are compact, in-line devices with two checks in series, typically without the shutoffs and test cocks package of a testable DC assembly (1015).
| Feature | Dual check 1024 | Testable DC assembly 1015 |
|---|---|---|
| Two checks | Yes | Yes |
| Shutoffs + test cocks | Typically no (device) | Yes (assembly) |
| Field DP test | Not in the 5110 practical sense | Yes |
| Common use | Residential meter setters, appliance lines, non-testable continuous-pressure applications as approved | Containment/isolation where testing is required |
| Protection limits | Program-specific; generally not health-hazard workhorse like RP | Non-health backpressure/siphonage as approved |
Exam trap: 1024 ≠ 1015. Same “two checks” story, different testability and installation class. Another trap: dual checks are not automatic substitutes for RP on health hazards.
Related number sometimes seen in broader plumbing: ASSE 1012 (backflow preventer with intermediate atmospheric vent) appears on appliance lines (boilers, etc.) in many jurisdictions—recognize 1012 as another non-testable intermediate-vent style device, distinct from 1013 RP.
Why Non-Testable ≠ “Not Required”
- Codes still mandate them. Fixture protection laws do not vanish because a device lacks test cocks.
- Hazard control still works mechanically. An AVB that is correctly applied still breaks siphonage even if you cannot hang a gauge on it.
- Programs mix strategies. Containment may use a testable RP at the meter while isolation uses AVBs and hose bibb breakers at fixtures.
- Surveyors and testers share a language. ASSE 5120 survey work and 5110 testing meet at recognition: if you cannot name devices, you cannot describe a premises.
- Liability and public health. “I only test 1013s” is not an excuse to ignore a hose in a tank if your assignment includes inspection notes.
What you typically do not do:
- Invent a fake differential-pressure “pass” for a 1001.
- Sign a USC-style assembly test report as if a 1024 were a 1015.
- Remove required non-testable devices because they are inconvenient.
What you do:
- Identify standard numbers and correct application classes.
- Flag continuous-pressure abuse of AVBs, missing hose bibb protection, and defeated air gaps.
- Direct owners to proper testable assemblies when the application demands annual testing and higher protection.
Device Number Recognition Table (Memorize)
| ASSE No. | Common name | Testable assembly? | Protection snapshot (typical) |
|---|---|---|---|
| 1001 | Atmospheric vacuum breaker (AVB) | No | Backsiphonage; not continuous pressure |
| 1011 | Hose connection vacuum breaker | No | Hose bibb backsiphonage protection |
| 1012 | Backflow preventer with intermediate atmospheric vent | No | Appliance/continuous specialty as listed |
| 1013 | Reduced pressure principle assembly (RP) | Yes | Backpressure + backsiphonage; health-capable |
| 1015 | Double check valve assembly (DC) | Yes | Backpressure + backsiphonage; non-health as approved |
| 1020 | Pressure vacuum breaker (PVB) | Yes | Backsiphonage; continuous pressure |
| 1024 | Dual check valve | No | Two checks; non-testable device class |
| 1047 | Reduced pressure detector assembly (RPDA) | Yes (main + bypass) | RP protection + metered low-flow detection |
| 1048 | Double check detector assembly (DCDA) | Yes (main + bypass) | DC protection + metered low-flow detection |
| 1052 | Hose connection backflow preventer (hose connection type) | No (device class) | Hose connection protection with enhanced features vs basic 1011 as listed |
| 1056 | Spill-resistant vacuum breaker (SVB) | Yes | Backsiphonage; continuous pressure; reduced spillage |
Practical four for ASSE 5110 hands-on: 1013, 1015, 1020, 1056.
Detector pair: 1047, 1048.
Non-testable recognition set: 1001, 1011, 1012, 1024, 1052 (+ air gap as method).
Drill this table until number → name is automatic. Many written items are pure identification under time pressure.
How Recognition Shows Up on the Job
Example walk-through on a commercial property:
- Meter containment: 1013 RP (testable)—you test annually.
- Fire service: 1047 RPDA—you test mainline protection, note meter, manage impairment.
- Irrigation: 1020 PVB or 1056 SVB—you test; confirm 12-inch elevation.
- Restroom flush valves: 1001 AVBs—you recognize; you do not hang the DP gauge as on an RP.
- Wall hydrants: 1011/1052—recognize; replace if broken/missing.
- Boiler makeup specialty: 1012 device—recognize intermediate vent type; not a 1013.
- Residential branch: 1024 dual check in a setter—recognize non-testable dual check ≠ 1015.
That single property uses almost every row of the table. Testers who only memorize RP steps feel lost; testers who own the table read the site like a map.
Boundaries: Tester vs Repairer vs Surveyor (Preview)
- Tester (5110): field-test testable assemblies; recognize devices; report results.
- Repairer (5130 path): rebuild failed assemblies when credentialed/permitted.
- Surveyor (5120 path): systematically identify cross-connections and prescribe protection types.
Even as a tester-only, recognition of non-testable devices prevents unsafe advice (“just put an AVB on that pumped chemical line”) and improves communication with purveyors.
Key Points to Lock In
- Non-testable means no USC-style shutoff/test-cock DP test—not “optional protection.”
- Air gap = physical separation; ultimate, inspection-based protection.
- 1001 AVB = backsiphonage, not continuous pressure, typically no test cocks.
- 1011 / 1052 = hose connection protection devices.
- 1024 = dual check device ≠ testable 1015 DC assembly.
- Testable core: 1013, 1015, 1020, 1056 (+ detectors 1047/1048).
- Memorize the number recognition table—it is pure points on the written exam.
Why is a non-testable device still important even though an ASSE 5110 tester does not perform a differential-pressure field test on it?
Which statement correctly contrasts ASSE 1001 and ASSE 1020?
Match the ASSE numbers to the correct product names: 1013, 1024, 1048, 1056.
Which product is generally treated as a non-testable hose-connection device rather than a full shutoff-and-test-cock assembly like a 1013?