How much clearance should an AED case interior have?

Answer: 25 to 30 mm each side. Under 25 mm the lid must be forced, over 40 mm the unit shifts.

What is the real difference between two latches and four?

Answer: About 1.2 seconds. Four spread pressure more evenly but need both hands; two plus a centre button open in one.

Does a wall-mounted AED case need a relief valve?

Answer: Where temperature swings exceed 30 degrees, yes. Without one the vacuum holds the lid with over 30 kg of pull.

Where should the inspection record sit?

Answer: In an A6 slot inside the lid, on the same face as the seal, so it is seen whenever the case opens.

Which criterion is most often missed?

Answer: Depth. Buyers measure length and width, forget the height taken by a handle, then find the lid will not close.

AED Case Selection Guide: Five Criteria That Decide Fit

Quick answer: Judge an AED case in this order: interior fit, opening time, sealing and relief, mounting and security, inspection visibility. The first two decide whether it works, the last three whether it can stay on a wall.

AED Case Interior Fit Against the Device
Opening and Retrieval Time
Sealing and Pressure Equalisation
Mounting, Security and Inspection
Scoring the Five Criteria
FAQ

1. AED Case Interior Fit Against the Device

An AED case interior is sized from the device plus clearance, not from outside dimensions. Most biphasic units measure 300×230×90 to 340×280×110 mm, so a 420×320×130 mm interior covers the common models with 30 mm each side.

Device (mm)	Interior (mm)	Clearance	Insert
300×230×90	360×290×140	30	single cavity, 3 mm pad
340×280×110	400×330×160	30	two layers, pads in lid
260×200×80	320×260×130	30	two retaining ribs

Under 25 mm the handle presses into foam and the lid must be forced; past 40 mm the unit slides and shears the walls. Depth is most often missed: 30 mm of foam at ten percent compression leaves about 97 mm usable, plus 25 mm in the lid.

2. Opening and Retrieval Time

Two seconds, one hand, standing to device out, is the pass line. Four latches cost 1.2 seconds more than two, and the handle is rated 25 kg. The hinge stops at 100 degrees so the lid stays put.

AED case: olive green body closed, two black latches, folding metal handle with a round centre lock button, grid ribs on the lid

On scene one hand is often all there is. With the lock button at the centre of the handle, an AED case opens in one press and lift, leaving the other hand free. Clearance of 25 mm takes a winter glove; under 20 mm the glove jams on the grip. A hinge short of 90 degrees lets the lid drop back.

3. Sealing and Pressure Equalisation

IP66 and IP67 differ only in immersion: spray against short soaking. A sheltered wall point needs IP65, an open platform IP66, a wash-down bay IP67. A double-lip gasket traps air between 3 mm lips, so pressure drops before water reaches the interior.

Sealing well creates a second problem. At 50 degrees by day and 0 at night, cooling air leaves a vacuum holding the lid with over 30 kg of pull; a 0.2 bar relief valve on the short side releases it without using interior space.

Location	Rating	Relief valve	Temperature
Sheltered exterior	IP65	needed	-5 to 50 C
Open platform	IP66	needed	-10 to 55 C
Wash-down bay	IP67	needed	-5 to 45 C

Polypropylene turns brittle at minus twenty, and the body drops from a 1.2 m to a 0.8 m test height.

4. Mounting, Security and Inspection

Mounting height is 1100 mm to the lid edge, so the wrist stays neutral. The bracket is rated 40 kg, three times a loaded case, and a 3 mm coated cable loops body to bracket.

AED case: black case closed at an angle, two front latches, round pressure valve on the left short side, vertical wall ribs

Inspection of an AED case fails when nothing is visible. A 30 percent clear panel reveals a disturbed insert without opening, and an A6 slot inside the lid keeps the record beside the seal.

Security and access conflict. A padlock adds two seconds and a key to manage; a one-time seal shows an unauthorised opening and breaks in one pull, and at a 30 day cycle it is cheaper.

5. Scoring the Five Criteria

Criterion	Weight	Pass line	Usual failure
Interior	30	25 mm side clearance	depth from device only
Opening	25	one hand, two seconds	four latches, two hands
Sealing	20	IP65 or better, with relief	rating marked, no valve
Mounting	15	bracket rated 40 kg	four expansion bolts
Inspection	10	insert visible unopened	no record slot

Weighted to 100, below 70 should not go on a wall and below 55 belongs indoors. Interior fit takes 30 because a new device forces a new case, inspection 10 because management can compensate.

When criteria conflict, sealing and opening win: weak sealing fogs the interior and slow opening delays the analysis.

Conclusion

The order matters: interior fit decides whether the device goes in, opening whether it arrives in time, sealing and mounting whether it can hang for years, inspection whether hanging still means anything. Score the five on one sheet and choosing an AED case becomes a matter of conditions.

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.