Why portable toilets smell and rust — and how we solve both

Every portable toilet in the world, whatever system it uses, runs into the same two problems: odor and rust. This article explains why that happens regardless of system, and how Container To Build's units are designed to solve both.

Portable toilets use two main systems

The difference between portable toilet systems comes down to where the waste tank sits:

• Tank-under-booth system — a waste tank attached directly under the booth, waste drops straight in. Easy to move, suits temporary work.
• Buried septic-tank system — the tank is buried underground and doubles as a treatment tank. Suits more permanent installations.

Zoomed out, the world's sanitation systems split the same way: pump-and-collect (emptied later) versus direct discharge into a septic tank — and among countries, Japan has taken toilet technology the furthest.

Japanese technology: waterless systems

Japan developed toilets that need no flushing water at all, using mechanical force instead:

• Air-pump systems — air pressure plus a small amount of water carries waste to the tank
• Motor-driven systems (Shattlet-type) — a motor's rotational force carries waste instead of a large water flush

Both save large amounts of water, and a wide variety of other toilet types have been built on the same idea since.

Why the old systems (pump-and-collect / septic) haven't disappeared

Here's the interesting part: even after Japan built powered toilet systems, the traditional pump-and-collect and direct-discharge systems are still in everyday use alongside them — they were never fully replaced. That's because the traditional system is already a complete, settled design: the new systems (air-pump/motor) need electricity to run, while pump-and-collect / direct-discharge relies only on the natural pull of gravity on water — as long as the tank sits lower than the toilet bowl, it works with zero energy input at all. It is, in that sense, the most energy-efficient system there is.

The shared weakness of every system: odor and rust

Whatever the system, as long as the waste tank sits close to the booth, two problems are unavoidable:

• Odor — smell from the tank rises easily into the booth
• Rust — corrosive substances in waste eat away at the metal frame under the booth and the tank itself faster than normal

How our units solve this

Container To Build addresses both weaknesses directly:

• Block the odor path — the booth structure is designed to cut down as much as possible on smell rising back up
• Dedicated anti-corrosion coating — a corrosion-resistant coating is applied to both the frame under the booth and the steel waste tank, extending the unit's service life

These are two points we give special attention to in every portable toilet we manufacture, because they're exactly what most units on the market overlook.

In short

Interested in a portable toilet built specifically to cut odor and resist rust? Contact our team, or browse all toilet unit models we carry.