Karen Boyd, ASQ CQA Was the spec for max of 6 sec (or not to exceed 6 sec) validated by the manufacturer?
Was ~3 validated to be an acceptable or optimal functioning value for the device and its intended use? What about the functional levels of ~1, ~2, ~4, and ~5?
Regardless, you should definitely include a warning (w/symbols) indicating value must not exceed 6 sec, depending on the safety / risk attached.
You should attempt to match spec to DFU (or IFU) and ensure validations are performed to meet those conditions. Otherwise, why create a spec with an open range of what is "assumed" to be 1 to 6 sec?

James (Jim) Dent, LSSBB, DTMx2 I don't think there is enough details to answer this question.

While the design specification state "not to exceed 6 seconds"; what was the device actually designed and tested as: within 6 or within 3. If the test verification and validation indicates the device will be consistently not exceeding 3 seconds (which should be in the design records files) then the DFU / IFU might be correct in stating "not to exceed 3 seconds"; however, I would've have gone back and noted a revision to the original design spec limits, if the actual design tested and verified performed under 3 seconds.

Therefore, what is the actual performance and test verified parameter? Within 6 seconds, or within 3 seconds?

Alon Yaniv Thank you all for your comments.

The spec parameter of under 6 sec, is what is common in this field.

The DFU, deals with the consumable aspect which depends on the variable length of it.
For example: a consumable of 5 meters tube and a 3 meter tube will have different results, 5 sec and 3sec respectively.

Both of which are in spec.

I find it logical that the DFU will show the actual parameters, so the doctors will have better understanding of the products functionality.

Giving them the spec value, will only cause confusion and ambiguity.

Karen Boyd, ASQ CQA Thank you for clarifying, Alon.
If I understand you correctly, it seems that a simple chart, identifying which tubes size corresponds to which spec parameter (sec.) would be an ideal way for consumers / doctors to use the DFU.
This way, if a doctor is using a 3 meter tube, the corresponding spec would be 3 sec. and so forth, depending on tube length in use.