The conclusion: a report does not expire, what lapses is the match between the report and the product
The question we hear most is how many years a test report stays valid. The question itself is framed wrong. A test report is a record of how a particular submitted sample behaved under a particular set of conditions. It records a fact, and facts do not expire. What genuinely lapses is the correspondence between that record and the product you are selling today.
So when you judge whether a report can still be used, do not look at the issue date. Look at these three things:
- whether the model, configuration and key components the report covers are the same as the current product;
- whether the standards the report cites are in the current valid state;
- whether the situation in which the report is being used imposes any additional time-related requirement on the report itself.
The first two decide whether the report still holds. The last decides whether it will be accepted. Keep the three separate rather than blending them into a vague notion of validity. Wheelchair test methods are organised by part in the ISO 7176 series and the GB/T 18029 series, and requirements for the complete powered chair can be referred to in EN 12184; the specific parts are executed according to the corresponding part, confirmed against the current valid version of the standard text.
The four things people mean when they say validity
| Where the claim comes from | What it actually means | Who decides it | What makes it lapse |
|---|---|---|---|
| The test report itself | A factual record of the submitted sample | The laboratory | No cut-off date; it loses correspondence as the product changes |
| Tender or procurement documents | A requirement that the issue date fall inside a given window | The buyer | The issue date falls outside the window |
| Customer or channel entry audits | A requirement for a more recent report as evidence of in-production consistency | The channel | The channel revises its audit rules |
| Management-system and technical file upkeep | Technical documentation must stay consistent with the product in production | System requirements and the responsible authority | The product changed and the files were not updated |
The middle two rows and the last row cause the most trouble. A tender window is a purely commercial requirement with no technical content: the report is technically sound, but the document says the issue date has to sit inside a certain window, so another round has to be arranged. Technical file upkeep is an internal management problem: the product changed, the files did not follow, and the audit records a non-conformity on the spot.
Which changes trigger retesting
This is the core question the article exists to answer. The table below is organised by what you changed rather than by standard part, because when a factory makes a change it is thinking about parts and cost, not about parts of a standard.
| Change | Retest triggered | Direction usually affected | Judgement point |
|---|---|---|---|
| Frame material or forming process changed | Triggered | Strength and durability | If the load path changes it must be redone |
| Frame structure or key dimensions adjusted | Triggered | Strength, stability | Whether the centre of gravity position moves |
| Seat and backrest mounting interface changed | Triggered | Strength, dimension-related | Whether the load transfer path changes |
| Wheel or tyre specification changed | Case by case | Stability, braking | Whether outer diameter and friction characteristics change |
| Braking device design changed | Triggered | Braking | Whether the braking principle is the same as before |
| Folding mechanism design changed | Triggered | Strength, durability | Whether loading at the hinge points changes |
| Control system or battery design changed | Triggered | Electrical and battery | A topic of its own, see the links below |
| Surface finish or colour changed | Usually not triggered | None | Confirm it does not affect flammability and corrosion claims |
| Supplier changed with the specification unchanged | Case by case | Depends on the part | Needs comparability evidence to support it |
| Label and instruction content changed | No test triggered | Document check | Technical files must be updated in step |
The two case-by-case rows are where opinions diverge. Here is a workable rule: if you cannot show in writing that the situation before and after the change is equivalent in loading, dimensions and material characteristics, treat it as triggered. The value of that sentence is that it puts the burden of proof back on the designer. No equivalence evidence, no gamble.
A cost scenario that really happens
The usual shape is this. To reduce cost, a length of tube in the frame is switched to a same-specification product from another supplier. The specification sheet says they match, purchasing handles it as a no-change item and quality is never told. Some time later the customer runs an in-production consistency audit, pulls a unit that is on sale and retests it, and the strength direction does not conform.
The price at that point includes disposition of batches already shipped, a hold at the channel, the lead time to retest and reissue the report, and heightened scrutiny of every subsequent change by the auditor. Whereas an equivalence assessment at the moment of the material change would have needed only a comparison of material characteristics and one targeted verification. That is what free at the concept stage and rescheduling plus batch disposition after shipment actually look like.
For project scope on manual products, compare against manual wheelchair testing; the electrical and battery chain on powered products follows a separate logic, see electric wheelchair testing.
Cases where the report still holds but the files need updating
Several situations do not void the conclusion of the report, yet will get it questioned in use, so handle them in advance:
- The cited standard is no longer in the current valid state. Assess the differences and arrange supplementary testing where necessary. No specific edition is written here; the current valid version governs throughout.
- The client entity information changes. After a change of company name or registered address, the report has to be updated according to the laboratory's own rules.
- A sales configuration is added. The original report covers one configuration combination; a new configuration must first be assessed against the original coverage, and anything outside it is handled as a new configuration.
- The product name or trade name is adjusted. The conclusion is unaffected, but the correspondence between the technical files and the report must still be explainable.
What these have in common is that the document changed and the product did not, so the handling cost is low. Left undone, though, they tend to bite at exactly the moment of an audit or a bid.
The order in which a buyer should check a report
This order works for a manufacturer's own self-check as well as for a buyer's verification:
- Check the model and configuration the report covers against the contract item.
- Check the list of items in the report against the performance directions you care about.
- Check whether the cited standards are in the current valid state.
- Check the description of the submitted sample, whether it was a hand-built prototype or a production unit.
- Check whether the laboratory's accredited scope covers those items.
- Check whether any change statement or supplementary report is attached.
Verified in that order, the great majority of reports that look fine but cannot actually be used are stopped at the first two steps or at the sample description. The sample description deserves particular attention: a hand-built prototype does not carry the same consistency argument as a production unit, and an in-production consistency audit will press the point.
Change-management self-check table
| Point in time | Self-check action | Consequence of skipping |
|---|---|---|
| When the change is proposed | Complete a change impact assessment noting whether loading, dimensions or material change | Nobody assesses material substitutions, and they surface together at audit |
| At change review | Decide whether retesting is triggered and record the basis | The judgement varies by person and is inconsistent over time |
| Before the change is implemented | Arrange the necessary retest or equivalence verification | Batches already shipped face disposition |
| After the change is implemented | Update technical files, instructions and the rating label in step | Files do not match the hardware and are recorded as non-conforming |
| Before a bid or an audit | Check report coverage against the configurations on sale | Last-minute testing that will not fit the delivery date |
| Periodic review | Check whether cited standards are still in the current valid state | The report is questioned and has to be reassessed |
The point of the table is to bind change and retest judgement into one process. Most companies that get into trouble do not lack the technical judgement; their change process simply has no column for it, so the judgement never gets the chance to happen. For how comparable situations were handled, see testing cases.
A note on accreditation scope
When you verify a report you will see accreditation marks, so let us be precise. An accreditation mark only demonstrates that the laboratory holds the corresponding technical competence within its accredited scope; it does not constitute a commitment regarding market access outcomes in the target market. Whether the report is accepted by the target market or by the buyer also depends on the requirements of the local competent authority, the specific provisions of the procurement documents and the completeness of the technical documentation. So what has to be confirmed before placing an order is whether the items you need fall inside that laboratory's accredited scope.
If you want the change list reviewed
If you are holding a report that is a few years old and have accumulated several changes that never went through an assessment, put the change list and the report coverage side by side before your next bid or audit. SUNGO Mobility Testing Lab is the dedicated wheelchair and mobility aid testing lab within our group, accredited by CNAS, CMA and IAS (USA), with laboratories in Shanghai and Hefei; for the standards structure start with testing standards and for the project breakdown see testing services. We can sort your changes into must retest, verification recommended and document update only, so a limited budget goes to the items that will actually be questioned. Call +86 132 4819 8029, or request a quote and send over the model list and the change records.