Can cleaning and disinfecting cases run in one pass with one bottle?

Answer: No. Cleaning lifts soil while disinfection kills organisms, and the two want opposite conditions. Merging them misses both and leaves film in the groove.

Is hypochlorite at 500 mg/L safe?

Answer: Milder than 5000 mg/L, still not safe. It raises PP roughness by 0.2 μm and swells the gasket 3 percent, but it still pits 304 hardware, so two water wipes stay mandatory.

How long after an ethanol wipe can the lid close?

Answer: Three to five minutes at room temperature, with groove corners blown out. In a hurry, 60 s of cold air works; air above 60 °C softens a TPE section.

Is 30 min of UV enough inside a case?

Answer: For surfaces yes, for gaps no. Lid grooves, hinge bores and counterbores stay in shadow, so treat the lamp as support; gaps need an agent.

The case still smells after disinfection. Can it go back into use?

Answer: Trace the smell. Quat residue is strongest, and a tacky feel means the film survived; a lingering chlorine note means the same, which a leak-down over 2 kPa confirms.

Cleaning and Disinfecting Cases: Safe Agents

Quick answer: A case only tolerates what its weakest material allows, which is why 5000 mg/L hypochlorite for 30 min lifts PP roughness from Ra 1.6 to 2.8 μm.

Four Materials Decide the Answer
Oxidisers: Hypochlorite Attacks the Gasket First
Alcohols and Quats: Time in Seconds, Not Minutes
Peroxide and UV: Two Damages That Leave No Mark
Three Settings, One Retest
FAQ

1. Four Materials Decide the Answer

Inside a case sit four materials, not one: the shell, the gasket, the print, the foam. An agent is judged against the weakest. Soak PP at any pH from 2 to 12 for 24 hours and it sheds under 0.3 percent of its mass; hold an EPDM gasket above pH 11 for the same time and hydrolysis has started.

Cleaning and disinfecting cases has to be written around the seal, not the wall.

The print is the third weak point. Cross-cut adhesion to ISO 2409 reads grade 1 out of the mould; six chlorine wipe-downs take it to grade 3. Foam is worse: 30 s in 5000 mg/L hypochlorite carries liquid 2 mm deep, past any cloth.

Agent, setting	Shell	Gasket	Print	Foam	Verdict
Hypochlorite 5000 mg/L, 30 min	Ra to 2.8 μm	+8 percent	grade 3	wet 2 mm	reject
Ethanol 75 percent, 60 s	no change	within 3 percent	4 passes	flash-off	limited
Quat 2000 mg/L, 10 min	no change	plasticiser drawn	none	tacky	limited
Peroxide 3 percent, 30 min	no change	within 2 percent	none	intact	acceptable
UV, 30 min	ΔE 1.5	chalked	pigment fades	brittle	surface only

Strength multiplies concentration, dwell and temperature, so doubling one means pulling the other two back. A 40 °C solution reacts twice as fast as the same mix at 20 °C, turning 30 min into an hour in a sun-warmed case. Temperature never appears on the label.

2. Oxidisers: Hypochlorite Attacks the Gasket First

Hypochlorite at 5000 mg/L is the hospital-floor strength. A PP coupon soaked 30 min comes out at Ra 2.8 μm instead of 1.6 μm, with cracks along the weld lines. Past Ra 2.5 μm the surface holds soil, so the next clean takes longer.

Cleaning and disinfecting cases at the outer wall: black case closed at an angle, two red catches biting the lid edge, rounded corners

The gasket fails first. Thirty minutes swells an EPDM section by 8 percent; two hours takes it past 10 percent, and 10 percent is the line. A section over that will not seat in its groove, the lid edge never bottoms out, and the seal is done.

Residue is what costs money.

Drying is not removing. Chloride under screw heads waits for the next damp spell, and 304 springs pit within four weeks. Where chlorine is unavoidable, cap contact at 30 min, hold strength at or below 1000 mg/L, wipe twice, and dry below 45 °C for 6 h.

3. Alcohols and Quats: Time in Seconds, Not Minutes

Ethanol at 75 percent is the easiest option in the cabinet: it flashes off and moves PP and EPDM by under 3 percent of mass. The limit is dwell and frequency. Keep one pass under 60 s and stay at or below 4 passes a month; past that the print loses gloss first.

Quats go in at 1000–2000 mg/L, 10 min. The shell barely notices, yet the residue pulls moisture into the groove and turns tacky, and once the lid closes that film is trapped against the sealing face. Leak-down climbs from 0.6 kPa to 2.2 kPa in 60 s, over the 2 kPa line.

Write the pH rule separately: 4 to 10 works, anything above 11 stays out. Caustic only dulls PP, but it hydrolyses the silicone backbone, so the two cannot share one scale.

One detail runs against instinct. Ninety-five percent ethanol works worse than 75 percent, because the stronger mix coagulates protein and shields what lies underneath, while attacking print harder. For cleaning and disinfecting cases, stay on 75 percent.

4. Peroxide and UV: Two Damages That Leave No Mark

Three percent peroxide held 30 min breaks into water and oxygen, the lowest-residue option where carry-over matters. PP shrugs it off; copper alloy springs and plated rivets do not, so hardware gets a thin silicone film within 48 h.

Cleaning and disinfecting cases inside the tub: black case standing open, bare lid and empty base with no liner, red catches folded out

Ultraviolet runs another track. Thirty minutes shifts PP yellowing to ΔE 1.5; by 2000 hours impact strength keeps around 70 percent under the GB/T 16422.3 cycle. UV travels in straight lines, so lid grooves and hinge bores sit in shadow. For cleaning and disinfecting cases the lamp covers exposed surfaces only; gaps still need chemistry.

Neither damage announces itself. Both simply change the material.

5. Three Settings, One Retest

Medical use has the longest kill list and runs 1000 mg/L chlorine or 75 percent ethanol for 10 to 30 min, then two water wipes. Laboratories lean on quat at 2000 mg/L for 10 min. Food-contact surfaces take 3 percent peroxide for 30 min, where residue limits bite.

Setting	Agent	Strength	Dwell	Follow-up
Medical	hypochlorite	1000 mg/L	30 min	2 wipes, dry 6 h
Medical	ethanol	75 percent	60 s	air dry
Laboratory	quat	2000 mg/L	10 min	1 wipe
Food contact	peroxide	3 percent	30 min	2 wipes
Rotation	quat	1000 mg/L	10 min	tub only

The retest takes 2 readings, no shipping. A 60 s leak-down at 2 kPa or less says the sealing face carries no film; three caliper readings say whether the gasket grew past 0.3 mm.

Log 3 fields: agent and strength, dwell, retest figure. Once the chemistry changes, they are the only way to compare rounds.

Conclusion

The hard part of cleaning and disinfecting cases is the finish, not the kill: agent left in a groove, in foam or on print shows up four weeks later. Pick chemistry against the gasket rather than the shell, fix dwell at 60 s and 4 passes a month for ethanol, 30 min and 1000 mg/L for chlorine, then close each round with two water wipes, drying below 45 °C for 6 h and a leak-down under 2 kPa. Hold all three and a case survives three years of cycles; skip the finish and the gasket goes first.

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.