Share governance, never measurement conclusions.
An underwater-radiated-noise survey controls an acoustic measurement chain, vessel passes, hydrophone geometry, background and propagation context. An onboard illumination survey controls working planes, point grids, lux-meter response, supply state, daylight and fittings. A sea trial or commissioning programme may witness both, but a valid result in one discipline supplies no evidence for the other.
State the purpose, applicable method and edition, required output, comparison or acceptance criterion, report recipient and decision owner separately. An ISO procedure, IMO guideline, IEC equipment standard or general convention does not create one universal pass limit or certify a supplier. Where a contract or approved drawing adds requirements, cite the exact revision rather than merging them into an undocumented checklist.
| Item | Discipline | Required decision | Quantity / units | Governing basis | Decision owner | Excluded conclusion |
|---|---|---|---|---|---|---|
| DEC-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| DEC-02 | ___ | ___ | ___ | ___ | ___ | ___ |
Agree who observes, directs, accepts and records.
List the master or operational authority, vessel representative, yard or maker, measurement lead, navigation or electrical lead, contract witness and eventual acceptance owner. Record who can pause a pass, alter machinery, switch a circuit, approve a safe blackout simulation, accept a deviation or release a report. Attendance alone does not transfer these authorities.
Brief witnesses on the intended state, safe stand-off positions, communications, time synchronisation, data confidentiality and stop criteria. A signature should confirm what was observed and which record revision was available; it should not imply class, flag, customer or employer endorsement unless that organisation has formally authorised the role and wording.
| Role | Named person / organisation | Authority | Briefing time | Records witnessed | Signature scope | Limitation |
|---|---|---|---|---|---|---|
| WIT-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| WIT-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| WIT-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Lock the test matrix before the first result.
Retain the approved procedure, drawings, trial or grid schedule, instrument list, calibration evidence, data naming convention, tolerances, environmental controls, acceptance basis and report revision. Identify planned witness points and the route for changing them. The earlier URN trial-readiness and illumination grid resources describe how to prepare these discipline-specific controls; this record begins at witnessed execution and close-out.
Version changes must show author, time, reason and approval. Never replace the executed plan silently after seeing a result. If a prerequisite is missing—such as site qualification, safe electrical switching, a defined plane or synchronised navigation—record the gap and decide whether the activity is postponed, repeated or released only as a limited engineering observation.
| Control | Approved reference | Planned state | Executed state | Difference | Authority decision | Evidence file |
|---|---|---|---|---|---|---|
| PLAN-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| PLAN-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| PLAN-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Decide run validity before combining spectra.
For every retained acoustic window, link the raw hydrophone file to time, position, closest approach, aspect, hydrophone depth, vessel draught and trim, speed through water and over ground, shaft or propeller RPM, pitch or load, auxiliary lineup, water conditions and background record. Preserve calibration, sensitivity, gain, bandwidth, clipping and synchronisation checks. Inspect repeat-run consistency before averaging or normalising results.
ISO 17208-1 addresses precision comparison measurements in deep water; Part 2 addresses source-level determination from deep-water measurements; Part 3 addresses shallow-water procedures. These routes are not interchangeable. When weather, current, traffic, geometry, machinery instability or instrumentation departs from the selected route, retain the record and explain its consequence. A smooth spectrum is not proof of a valid contractual pass.
| Run / window | Vessel state | Geometry / site | Background / interference | Chain / timing | Deviation effect | Retain / repeat / qualify |
|---|---|---|---|---|---|---|
| URN-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| URN-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| URN-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Keep every lux value tied to a plane and lighting state.
Identify the space, task, drawing point or grid cell, measurement plane and height, sensor orientation, lux-meter identity, calibration and field check. Record normal or emergency supply, circuit, dimming and automatic-control state, lamp warm-up, supply voltage where relevant, daylight inclusion or exclusion, blinds, doors, temporary lights, failed or dirty fittings, diffusers, obstructions and surveyor shading control.
Show individual readings before calculating any average, minimum or defined uniformity ratio. Do not combine task points, escape-route points, vertical controls and horizontal grids unless the governing basis expressly treats them together. Functional changeover, emergency illuminance, source endurance and low-location-lighting performance are separate decisions and require their own safe procedures and quantities.
| Space / grid / point | Plane / height | Supply / controls | Daylight / fitting state | Meter evidence | Deviation effect | Retain / repeat / qualify |
|---|---|---|---|---|---|---|
| LUX-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| LUX-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| LUX-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Classify the consequence, not just the event.
A deviation may affect safety only, data traceability, method conformance, comparison validity, uncertainty, the acceptance decision or merely administration. Record when it began, the affected run, point or file, how it was detected, immediate containment, evidence retained and the person authorised to decide. Never delete an invalid result simply to make a report look complete.
Disposition options can include accept with no technical effect, accept with a quantified limitation, repeat the affected item, redesign the method, issue an engineering-only observation, or stop the campaign. The acceptance owner—not the most convenient party—decides whether a contractual deviation is acceptable. Technical staff should state evidence and consequence without inventing another organisation’s approval.
| Deviation ID | Affected record | Detection / cause | Technical consequence | Immediate control | Disposition owner | Final status |
|---|---|---|---|---|---|---|
| DEV-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| DEV-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| DEV-03 | ___ | ___ | ___ | ___ | ___ | ___ |
This blank structure contains no completed vessel result, customer identity, certification, class or flag approval, external review, acceptance, submission, backlink or testimonial.
Separate data correction from physical modification.
A measurement-system action may repair timing, replace a damaged cable, repeat a calibration check, correct a point identity or restore an approved configuration. A vessel action may address a propeller or machinery condition, an operating restriction, fitting selection, aiming, cleaning, obstruction, control setting or electrical fault. The latter may require designer, maker, owner, yard, class or flag review before installation.
State the finding addressed, proposed mechanism, authorised instruction, responsible person, installed or executed state, configuration evidence, predicted effect and retest condition. Never alter raw data to simulate a correction. Processing changes must be versioned, reproducible and applied consistently. If several physical changes occur together, disclose that their individual contributions cannot be isolated.
| Action ID | Finding addressed | Action type | Approved instruction | Executed evidence | Predicted effect | Retest condition |
|---|---|---|---|---|---|---|
| ACT-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| ACT-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| ACT-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Quantify how closely the decision condition was repeated.
For URN, compare site and geometry, vessel draught and trim, hull and propeller condition, track, speed, RPM, pitch or load, auxiliaries, background, environment, acoustic chain, timing and processing. For illumination, compare point identity, plane, sensor orientation, supply, voltage, circuits, controls, daylight, warm-up, fittings, obstruction and meter. Record unavoidable differences before interpreting change.
Repeat the decision-relevant item, not a convenient proxy. A stationary hydrophone check does not verify a vessel-pass result; one bright lux point does not verify a room grid. Report measurement uncertainty or repeatability appropriate to the method, and distinguish measured change from normal variation. If comparability is insufficient, classify the result as limited rather than claiming verified improvement.
| Item | Baseline state | Retest state | Difference | Measured change | Uncertainty / repeatability | Verification decision |
|---|---|---|---|---|---|---|
| RET-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| RET-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| RET-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Close every finding with an explicit evidence state.
The release package should identify scope, procedure and edition, witnesses, instruments, calibration and checks, planned and executed conditions, raw-file map, processing or calculations, individual and summary results, uncertainty, deviations, actions, retests and limitations. Keep measured facts, calculated outputs, engineering interpretations and acceptance decisions visibly separate.
Classify each item as valid for the tested state, valid with limitation, repeated and superseded, not verified, outside scope or awaiting authorised acceptance. Preserve superseded records and revision history. Vessel Doctor may document technical evidence but does not claim that a class society, flag, client or environmental programme has accepted it unless a traceable decision from that party exists.
| Finding / deviation | Evidence state | Retest reference | Residual limitation | Technical reviewer | Acceptance owner | Release revision |
|---|---|---|---|---|---|---|
| CLOSE-01 | ___ | ___ | ___ | ___ | ___ | ___ |
| CLOSE-02 | ___ | ___ | ___ | ___ | ___ | ___ |
| CLOSE-03 | ___ | ___ | ___ | ___ | ___ | ___ |
Confirm the edition and vessel-specific basis.
- ISO 17208-1:2016 covers precision measurements of ship underwater sound in deep water for comparison purposes.
- ISO 17208-2:2019 addresses determination of source levels from deep-water measurements.
- ISO 17208-3:2025 specifies shallow-water measurement procedures and calculations.
- IMO MEPC.1/Circ.906 provides revised guidance for reducing underwater radiated noise from shipping.
- IEC 60092-306:2022 applies to luminaires and lighting accessories used in ships.
- Maritime Labour Convention, 2006, as amended includes accommodation-lighting guidance.
Confirm the current flag, class, contract, approved drawing, owner specification and safe operating procedure. These public records do not supply one universal acceptance value or approve a measurement provider.
Send the executed plan, deviations and decision route.
Provide the URN run matrix or illumination point schedule, applicable basis, instrument evidence, witness roles and unresolved deviations so a matched close-out scope can be agreed.
Request a witness or close-out scopeReview URN surveysReview illumination surveys