Which items matter most in Medical Case acceptance?

Answer: Seal, latch retention and envelope size: the first two keep contents dry, the third decides shelf fit.

Is immersion testing always required?

Answer: No. Pressure decay finds most defects; immersion arbitrates when a result is doubtful.

Should colour be judged by eye or by instrument?

Answer: Both. The instrument gives a number, the limit sample gives the range it may fall in.

How many first article samples should be kept?

Answer: Three: one filed, one for the supplier, one sectioned to check wall thickness.

How long are records kept?

Answer: One contract cycle plus a year, because emergency stock is opened long after delivery.

Medical Case Acceptance Standards: Test Items and Verdicts

Quick answer: A Medical Case passes only when every item is a number plus a condition: tolerance for geometry, pressure decay for the seal, a signed sample for appearance, a sampling plan for the lot.

Why a Medical Case Needs Written Verdicts
First Article Checks
Verifying Seal and Ingress Protection
Latch Hinge and Handle Endurance
Sampling Verdicts and Records
FAQ

1. Why a Medical Case Needs Written Verdicts

Disputes over a delivered lot are about wording, not looks: one side accepts the case, the other rejects it. Turn each item into a number and a condition, and the argument becomes arithmetic.

The four families are checked at different moments: geometry and appearance at the first article and patrol inspection, function at the first article and each lot, drop and static load at the first article and the annual type test. On a Medical Case they must be frozen while the tool is sampled.

Family	Items	Verdict
Geometry	Envelope, wall, flatness	Against tolerance
Function	Seal, latch, handle, drop	Pass or fail
Appearance	Colour, flash, sink marks	Graded

Grading matters as much as measuring: a leaking seal is critical, a stiff latch is minor.

2. First Article Checks

The first article comes from shots five to ten, measured after thirty minutes of cooling. The envelope is held to plus or minus 2.0 mm, the thinnest wall to 2.8 mm, and a feeler gauge may not enter under the base beyond 1.5 mm. Lid to body mismatch is the item most often skipped: a fingernail across the seam reads any step above 0.5 mm.

Medical Case: yellow front latch and handle root in close-up, four vertical ribs beside the latch, level parting line, no flash

Appearance is judged against a signed limit sample, not a sentence. Colour under D65 may differ from the sample by 1.5, and by 1.0 between body, latch and handle. Flash fails if a 0.3 mm feeler enters the parting line, and wall thickness under 2.5 mm at a corner usually predicts a drop split.

3. Verifying Seal and Ingress Protection

The seal is tested twice. Charge the closed case to 20 kPa, hold 60 seconds, and fail above 1.0 kPa, which catches a missing gasket and an opened splice. Then 30 minutes at one metre, wiped dry, walls checked for water, case weighed: a gain above 5 g fails.

The gasket is accepted as 55 plus or minus 5 Shore A and 25 to 30 percent compression, moulded as one ring with no splice. A spliced ring passes at room temperature and opens after four hours at minus 20 degrees Celsius.

Repeat both tests after four cycles between minus 20 and 55 degrees. Body and gasket shrink at different rates, so a Medical Case that passed cold can leak warm.

4. Latch Hinge and Handle Endurance

Latch life runs at 15 operations per minute to 5,000 cycles. At the last cycle it must still close with one hand and hold pressure. Cracks start at the arm root, so the part is checked at five times magnification and fails above 1 mm.

Medical Case: an open yellow case on grey, bare lid interior, compartments holding a coiled light rope, an orange ring and two clear pouches

A lid opened to 100 degrees must stay on the hinge stop without a strap. The pin is 304 stainless at 4 mm with 0.1 to 0.2 mm clearance, allowed to grow 0.15 mm over 3,000 cycles. The handle carries twice its 15 kg rating for ten minutes with no more than 2 mm of set.

Drop a loaded Medical Case at 1.2 m, three times on six faces, onto concrete at least 100 mm thick.

5. Sampling Verdicts and Records

Lots are drawn at inspection level II, with an acceptance quality limit of 1.0 for major and 2.5 for minor defects. A leaking seal is critical and not sampled. A lot of 501 to 1,200 units samples 80, accepting 2 and rejecting 3.

Lot size	Sample	Major Ac/Re	Minor Ac/Re
151 to 280	32	1/2	3/4
281 to 500	50	1/2	5/6
501 to 1,200	80	2/3	5/6
1,201 to 3,200	125	3/4	7/8

A record must let a second person repeat the verdict: batch and mould number, raw readings rather than the word pass, pressure figures, room temperature, date, and a batch code tracing to press and shift.

Conclusion

Acceptance is not a look over; it is a set of numbers someone else can recompute. Put tolerances, test conditions, a limit sample and a sampling plan on the inspection card, and the argument becomes a comparison of readings. Ask for raw data before price is discussed, and the Medical Case will not arrive unjudgeable.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.