STR EV-charger faults: a safety handoff study

Methodology

1. Scope and preregistration: Review one guest, device, or vendor report involving an EV charger, connector, cable, receptacle, breaker, charging session, heat, odor, visible damage, or loss of service. Freeze the property-local observation window, inclusion rules, cutoff, and codebook before reading outcomes. Include only traceable cases tied to a property and operational consequence. Exclude drills, demonstrations, duplicate notifications, unattributed recollections, and test-device events. This is a retrospective descriptive review, not an experiment, inspection, legal analysis, clinical assessment, or claim about STRVirtualAssistant performance. The research question is: Which records support a bounded response when a guest reports that a vacation-rental electric-vehicle charger is hot, damaged, unavailable, or behaving unexpectedly?
2. Evidence model: Capture guest wording, equipment identity, location, report time, visible condition, odor or heat as reported, vehicle state without unnecessary identifiers, power indication, access restriction, emergency instruction used, property acknowledgement, qualified electrician or vendor scope, finding, repair, guest update, and release authority. Preserve originals in approved systems and store controlled references in the study table. For each value, record source role, original time and timezone, retrieval time, correction history, and interpretation authority. Keep guest-reported, staff-observed, device-indicated, official-source-published, vendor-stated, manager-approved, contradicted, stale, and unknown as different codes. A sent message is not acknowledgement, a scheduled visit is not arrival, a vendor completion note is not independent verification, and silence is not evidence that a condition ended.
3. Source selection: Charging Electric Vehicles at Home, Electric and Hybrid Vehicles: Battery, Charging and Safety, Carbon Monoxide Questions and Answers, Smoke Alarms provide the closest primary or authoritative hazard context. Emergency Alerts, Privacy Framework, Data Security inform communication, privacy, security, or record control. Every listed source was checked on 2026-09-22. None studied this local population, assessed this company, or validated the workflow. A source may define a term or state general guidance; only traceable property artifacts support a statement about a reviewed case.
4. Sampling and comparison: Build a consecutive register for the frozen period rather than selecting memorable examples. Report counts for screened, included, excluded, duplicate, incomplete, conflicting, corrected, escalated, reopened, and unresolved cases. Compare complete event sequences with records where an initial label or final task status stands in for evidence. Stratify by property, occupancy, channel, reporter role, device involvement, after-hours status, and consequence before pooling. Show every denominator and do not combine categories with different decision rights.
5. Reliability: Two reviewers independently code an ordinary-and-exception sample without seeing each other's classifications. Log disagreement by field, identify whether wording, missing evidence, timestamp conversion, or authority caused it, and adjudicate against the codebook. After any rule change, recode a stable sample and retain both results. Agreement measures reproducibility only. It does not prove an observation true, an action safe, a source complete, or an outcome satisfactory.
6. Counterexample search: Look actively for an app error or interrupted session labeled as proof that building wiring is unsafe. Also look for visible damage or overheating dismissed because a remote dashboard shows the charger online. These cases test whether proposed fields preserve a decision boundary or merely reward complete paperwork. Keep negative cases, late corrections, and outcomes that contradict the first interpretation. A later benign result cannot erase an earlier unsupported claim, and an adverse result cannot prove that every earlier action caused it.
7. Sensitivity checks: Repeat tables after excluding the largest property group, automation-originated alerts, records without final acknowledgement, and cases reconstructed later. Vary stale-information cutoffs and complete-handoff definitions. If a pattern changes, disclose that dependency and narrow the conclusion. Treat missingness as a result because records may be systematically absent during severe, overnight, or cross-channel events.
8. Authority boundary: The assistant may relay the approved stop-use or emergency path, restrict access under policy, preserve observations, and coordinate qualified service. It cannot direct electrical troubleshooting, reset energized equipment, diagnose a fault, assess a vehicle, or authorize return to service. When immediate danger is possible, the current emergency procedure takes priority over research collection. Researchers do not delay response to complete fields. The review records which approved path was used, what remained unknown, and who accepted the next decision. Any proposed change needs an owner, exception path, review date, and retirement condition rather than turning an association into an automatic rule.
9. Limitations: Remote telemetry and messages cannot establish conductor condition, grounding, installation compliance, thermal history, fire cause, vehicle compatibility, equipment safety, or repair adequacy. Selection favors cases with retained digital artifacts. Properties, equipment, vendors, local rules, channel terms, guest behavior, staffing, connectivity, and severity differ. The study cannot estimate prevalence from a convenience sample, compare companies, calculate avoided harm, attribute causality, or establish a benchmark. Results apply only to included records, definitions, and cutoff and must change if later evidence changes a case.