Can one specification cover five sectors in case selection by industry?

Answer: No. Broadcast needs insert support, testing records, defence stacking. The compromise is one rating tier with insert and marking split, at roughly 15 percent more empty weight.

Is IP67 always better than IP65?

Answer: Not for a post opened a dozen times a shift. IP67 demands a stiffer seal; in case selection by industry, IP65 with a purge valve is easier to live with.

How wide should the temperature range be?

Answer: Ten degrees beyond the real transport environment. A summer van reaches 65 degrees, a winter hold -25, so -20 to 60 is too narrow.

Can the insert be added later?

Answer: Only if the height margin allows. A case with 8 mm spare can take one; a tight case will not close.

Is a printed label enough for marking?

Answer: Short term. A label lifts within seconds under alcohol; for records beyond three years, use laser or a plate.

Case Selection by Industry: Where Five Sectors Diverge

Quick answer: Case selection by industry runs in four steps: ingress rating and drop height, then temperature and sealing, then insert and hardware, then marking and traceability. Sectors differ less in appearance than in the ranges each step will accept.

Which Three Specs Decide It
Step One: Ingress Rating and Drop Height
Step Two: Temperature Range and Sealing
Step Three: Insert and Hardware
Step Four: Marking and Traceability
FAQ

1. Which Three Specs Decide It

Five sectors on one shelf, differing only in colour. Three specs separate them: ingress rating, drop height, and a third item that shifts by sector, whether insert support for broadcast gear, records for testing, stacking for defence supply, or a wipeable surface for medical equipment.

Case selection by industry begins with a short list: three items, the numbers, and the test behind each.

Sector	Primary spec	Secondary spec	Can be relaxed
Broadcast gear	Insert support for body and lens	Latch retention after drop	Marking method
Third-party testing	Ingress rating	Seal and repeatable closing	Colour
Defence supply	Stacking and shell stiffness	Weathering and salt spray	Insert finish
Medical equipment	Wipeable surface and seam seal	Drop height	Case weight
Emergency stock	Seal after long storage	Thermal cycling	Insert tolerance

2. Step One: Ingress Rating and Drop Height

Case selection by industry means putting two numbers in the enquiry, not the phrase waterproof and shockproof. In IP65 the second digit means water jets; IP67 one metre of immersion for 30 minutes; IP68 a depth and duration in writing. Drop height needs height, faces and cycles.

Higher is not better by default. Twenty-six drops at 1.2 m across six faces is a common empty-case baseline, but a loaded case loads the latches 30 percent harder, so a loaded corner drop is taken at 0.8 m.

Tier	Ingress	Drop protocol	Typical setting
Basic	IP54 dust and splash	0.8 m corner drop	Indoor transfer, vehicle
Standard	IP65 water jets	26 drops at 1.2 m, six faces	Field shoots, inspection
Reinforced	IP67, 1 m for 30 min	Six faces at 1.5 m	Outdoors, marine, response

Acceptance is measured: no latch opens, the seal face shifts under 1 mm, the diagonal under 2 mm.

3. Step Two: Temperature Range and Sealing

Case selection by industry treats temperature as two columns: working, typically -20 to 60 degrees Celsius loaded, and storage 10 degrees beyond, so -30 to 70. Quote one range and the supplier prices its easiest end.

Sealing rests on the O-ring and a pressure test. A 5.5 mm silicone cord in a groove cut to 75 percent of that diameter leaves 25 percent compression; less seeps water, more takes a set. Pressurise to 20 kPa, hold 30 seconds, allow 1 kPa.

Cooling a case from 45 to 5 degrees can build 15 kPa across the lid, so any post opened a dozen times a shift needs a purge valve at 0.35 bar.

4. Step Three: Insert and Hardware

Case selection by industry turns on the insert, which sets how much room the shell needs. EVA at 45 kg/m³ and 25 mm thick rebounds best at 10 to 15 percent compression; foam below 35 kg/m³ collapses within two closures. A 15 by 15 mm pick-and-pluck grid suits regular shapes; irregular items need a cavity cut to drawing.

Internal height is a sum: bottom foam, object height, lid foam, plus 8 mm. Under 5 mm of margin the lid never seats; over 12 mm the load travels.

Case selection by industry also fixes hardware before the tool is cut, since each item needs a hole or a boss, and bolt-on parts break first.

5. Step Four: Marking and Traceability

Case selection by industry ends with marking. Laser burns into the surface and survives 50 wipes with 70 percent alcohol; screen print fails by the third move; a 0.8 mm riveted plate suits changing data, at the cost of two holes.

Traceability needs a 12-digit serial, a 15 by 15 mm code and a batch, always 30 mm in from the lower right corner of the lid, plus a calibration date held behind the code.

Case selection by industry produces twelve to fifteen numbers on one page.

Conclusion

The rating decides whether water gets in, the drop whether the latches hold, temperature and sealing whether the lid still opens, insert and marking whether each shift is easy. Once the numbers sit on one page, quotes compare and acceptance becomes a measurement. Case selection by industry is not five rulebooks; it is one order of four steps.

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.