JAHKO Journal · Material Guide

Porous or Non-Porous: The Difference That Changes Hygiene

Poreux ou non poreux : la différence qui change l'hygiène

A sea-worn pebble and a piece of coral have both spent years in water. Take the coral in your hand: it's an architecture of a thousand small chambers, carved so something could take hold and grow inside — that's literally its function, a living coral hosts entire colonies within its pores. The pebble has no chambers. Water polished it patiently until there wasn't a single crevice left, nothing for anything to hold onto.

Your intimate object, structurally, resembles one or the other. Except at the microscopic scale, what settles in isn't marine life — it's whatever your body let pass through.

This isn't going to tell you which material to buy. It's going to teach you to recognize, by touch and by reading a product page, what belongs to the "coral" family — and what belongs to the "pebble" family.

What settles into the micro-cavities

A porous surface isn't dirty to the naked eye. It just has microscopic ridges — peaks and crevices invisible to touch — that water and soap never fully reach. That's where it happens.

The moment a fluid touches a surface, proteins and sugars settle onto it within minutes. Bacteria then latch onto that film, and once attached, start building what's called a biofilm — a colony protected by its own matrix, far more resistant to cleaning than a free-floating bacterium. The literature on reusable medical devices is clear on this: starting the cleaning process within the hour after use sharply limits the formation of a mature biofilm. After that, it's a different story.

A study published in Sexually Transmitted Infections (BMJ, 2014) tested this very concretely on intimate objects. Twelve women used two vibrators — one made of thermoplastic elastomer (the soft "jelly" type), the other silicone — then cleaned them with a commercial product. The result: 24 hours after cleaning, HPV was still detectable on 40% of the samples taken from the thermoplastic object. On the silicone one: zero. Same cleaning product, same protocol, two materials — two radically different outcomes.

This isn't surprising once you understand why a biofilm resists so well. Once settled into their protective matrix, bacteria can become up to 1000 times more resistant to disinfectants than the same bacterium floating free in water — it's the international ASTM standard that governs how the industry tests product effectiveness against biofilms, precisely because a disinfectant that works on an isolated bacterium can remain powerless against the same bacterium fortified in its cavities. The product didn't lie. The architecture of the material won.

Did you know two objects cleaned the exact same way can stay contaminated in such different ways?

The table that changes how you shop

Material Porosity Truly Cleanable Lube Compatible
Silicone platine Non-porous Yes, including disinfection Water; silicone-safe for glass/steel
Verre borosilicate Non-porous Yes, including boiling Almost anything
Acier inoxydable 316L Non-porous Yes, including boiling Almost anything
TPE / TPR Porous Partially, never deeply Water only; condom recommended
Jelly / PVC Highly porous No, surface never truly clean Water only; strictly personal use

A non-porous object stands out with one simple detail: the manufacturer can recommend boiling or full disinfection without fear of damaging the material. If the product page only says "clean with warm water and mild soap," with no mention of disinfection at all, that's already an answer.

The nuance also matters between the two left-hand columns. Borosilicate glass and 316L stainless steel withstand full sterilization — the clinical kind. Platinum silicone disinfects very well with a short boil, but remains, by its nature as a flexible polymer, a step behind the mineral rigidity of glass or metal. A difference of degree, not of safety — all three families remain more than sufficient for rigorous personal use.

The trap of unlabeled "silicone"

"Silicone" isn't a protected word. An object can be made from a blend of silicone and cheaper polymers, or simply coated in a thin layer of silicone over a porous material — and still carry the word "silicone" on the packaging, without technically lying.

The only method that actually identifies a polymer's real composition is called Fourier-transform infrared spectroscopy (FTIR) — it's the tool forensic labs use to analyze trace evidence, and the one industry uses to verify what's actually in a material before certifying it. It reads a sample's exact molecular signature. A smell, a texture, or a lighter flame don't come close to that level of precision — these homemade methods circulating online don't conclusively distinguish anything, and carry an unnecessary risk on top of it.

So there's no reliable test to run at home. The real protection is the source: a manufacturer who names their silicone precisely (platinum, medical, food-grade) and a seller who can answer the question instead of dodging it. An unusually low price for "100% platinum silicone" is information in itself.

Sharing an object: the clear rule

The study cited above has a direct implication here. According to the CDC (NHANES data), roughly 40% of people aged 15 to 59 carry some form of HPV at a given time — this isn't a rare infection you catch "by bad luck," it's one of the most common STIs, usually silent. And even well cleaned, a porous object can remain a carrier for at least 24 hours. That's not a reason to panic about what you already own — it's a reason to set one simple rule before sharing:

Has the material of your objects ever shaped a decision to share them, or not?

When to Stop and Ask a Professional

This article informs — it doesn't diagnose. If you're experiencing pain, infection, pregnancy, an IUD, recent surgery, or any doubt, the right next step is a healthcare professional, not a blog post.

Are you buying a shape — or a pebble, a surface that no longer offers anything to hold onto?

Next: Borosilicate Glass →

This article is educational and does not replace medical advice. If you're in pain, dealing with infection, pregnant, have an IUD, had recent surgery, or have any doubt, please speak with a healthcare professional.