ASSE 5130 common mistakes
ASSE 5130 · Understand the traps and how to avoid them.
Treating a reduced pressure principle assembly's relief valve discharge as a normal condition and recording the assembly as passing when the relief valve drips steadily during the test.
Candidates confuse the small discharge that can occur during certain test steps with acceptable operation, or they attribute the drip to debris and move on without investigating, because the differential check holds and they assume the assembly is fine.
What to do instead
Learn the specific failure criteria: any continuous discharge from the relief valve at normal supply pressure means the assembly fails. During testing, isolate and observe the relief valve after each check; if it drips, stop and diagnose the first check (supply-side check) or the relief valve seat, and record a failure rather than forcing a pass.
Using the wrong test kit or failing to verify gauge calibration and hose condition before testing, then reporting results based on an uncalibrated or damaged gauge.
Candidates focus on the assembly and overlook the test equipment, assuming any differential gauge reads accurately; they may also use a kit with hoses that leak or have been exposed to freezing, which skews readings.
What to do instead
Before every test, confirm the gauge has a current calibration certificate (typically annual), zero the gauge, inspect hoses for cracks and fittings for leaks, and perform a quick leak check on the kit. Record gauge serial number and calibration date on the test report. If the gauge is out of calibration, do not test.
Misidentifying the type of backflow assembly on site (e.g., calling a double check valve assembly a reduced pressure principle assembly, or confusing a pressure vacuum breaker with a spill-resistant vacuum breaker) and applying the wrong test procedure.
Candidates rely on the shape of the body or the presence of test cocks without checking the manufacturer's tag or the number and arrangement of test cocks and shutoff valves, and they may not have memorized the distinct test procedures for each assembly type.
What to do instead
Study the physical differences: RP has a relief valve and three test cocks; DC has two test cocks and no relief; PVB has two test cocks and no downstream shutoff; SVB has one test cock. Always confirm by reading the tag and counting test cocks before selecting the test procedure. Practice identifying assemblies from photos and descriptions.
Failing to properly account for the installation orientation and clearance requirements when surveying a site, such as missing that an RP assembly is installed below grade without drainage or that a PVB is installed where it can be subjected to backpressure.
Candidates focus on the assembly itself and forget the site conditions that affect compliance, or they assume that because the assembly is present it must be installed correctly. They may not have memorized the specific clearance and orientation rules for each assembly type.
What to do instead
Use a systematic site survey checklist: verify assembly type matches hazard, check orientation (horizontal/vertical as approved), confirm relief valve discharge location and drainage, check that PVBs are not installed where backpressure can occur and are at least 12 inches above the highest downstream piping, and verify air gaps and clearances. Review the installation manual for each assembly.
Incorrectly recording test results, such as omitting the gauge calibration date, failing to note the assembly make/model/serial number, or not recording the actual pressure readings for each check.
Candidates treat the test report as a formality and rush through it, or they are unsure which fields are mandatory and leave them blank. They may also transcribe readings from memory after the test instead of recording them in real time.
What to do instead
Memorize the required elements of a test report: date, tester name and certification number, assembly type/make/model/serial number, location, gauge make/model/serial and calibration date, individual check readings (e.g., static and residual pressures), pass/fail determination, and signature. Practice filling out a sample report completely for each assembly type.
During troubleshooting, replacing parts (e.g., relief valve seat, check valve springs) without first diagnosing the root cause, leading to repeat failures or introducing new problems.
Candidates may have limited field experience and jump to common fixes they have heard about, or they lack a systematic diagnostic sequence and instead guess. They may also fail to isolate the assembly properly before disassembly.
What to do instead
Follow a logical diagnostic sequence: isolate the assembly, observe symptoms under test, check for debris, worn seats, damaged springs, and proper seating. Use the test results to pinpoint which check is failing. Consult the manufacturer's troubleshooting guide. Replace only the faulty component and retest the entire assembly.
Misunderstanding the hierarchy of cross-connection control regulations, such as citing a local ordinance when a state plumbing code or federal requirement (e.g., Safe Drinking Water Act) takes precedence, or failing to recognize the authority having jurisdiction.
Candidates study only their local rules or generalize from one jurisdiction, and they may not have a clear mental model of how federal, state, and local regulations interact. They also may not know which agency enforces which requirement.
What to do instead
Build a regulatory hierarchy chart: federal (SDWA, EPA), state primacy agency, local health department, plumbing code. Learn that the most stringent requirement applies and that the authority having jurisdiction (usually the local water purveyor or health department) enforces cross-connection control. Practice scenario questions about which rule governs.
Applying the wrong degree of hazard to a situation, such as recommending a double check valve assembly for a high-hazard application (e.g., chemical injection, sewage) where a reduced pressure principle assembly is required.
Candidates memorize assembly types but not the hazard classification system, or they underestimate the risk because the connection seems minor. They may also confuse backpressure and backsiphonage risks.
What to do instead
Study the hazard classification: high hazard (health hazard) requires RP or air gap; low hazard (non-health) may use DC or PVB. Learn to identify high-hazard connections (e.g., anything with toxic chemicals, sewage, medical equipment) and match the assembly accordingly. Review examples of each hazard class.
Failing to follow safety procedures during testing and repair, such as not depressurizing the assembly before disassembly, not wearing PPE, or not checking for hazardous downstream conditions (e.g., chemicals) before opening the assembly.
Candidates focus on the technical procedure and overlook safety, or they assume the assembly is isolated when it is not. They may also be unfamiliar with the specific hazards of the site.
What to do instead
Always follow lockout/tagout, close and verify isolation valves, bleed pressure from test cocks, and wear appropriate PPE (safety glasses, gloves). Before disassembly, identify what the assembly protects against and take precautions against chemical exposure. Review safety checklists and practice safe work habits.
Incorrectly performing the differential pressure check on a double check valve assembly, such as failing to account for the static pressure loss across the first check or not closing the proper test cock at the right time, leading to inaccurate readings.
Candidates may not fully understand the test sequence for a DC assembly, which requires measuring the pressure drop across each check while isolating sections. They may confuse the procedure with that of an RP assembly.
What to do instead
Memorize the DC test procedure step-by-step: close downstream shutoff, open test cock #2 to bleed, then use the gauge to measure the pressure drop across check #1 (static) and check #2 (residual). Practice on a training bench until the sequence is automatic, and always record both static and residual readings.