Toilet Seat + Button · Moran

Close and Flush
Integration System

A toilet lid and flush button redesign that automates lid-closing and flushing — without requiring user action.

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Every flush without a closed lid
sends invisible aerosols
into shared air.

Public restrooms almost never have toilet lids. And even when they do, closing the lid before flushing requires a conscious act most people don't take. The result: every flush disperses pathogen-laden aerosols into the air around you.

Toilet aerosol plume experiment

What the science
says about
toilet plume.

1.5m
Aerosol height
Toilet plume reaches 1.5 meters within 8 seconds of an open-lid flush — completely invisible to the naked eye.
5ft
Spread radius
Aerosols contaminate floors, walls, and surfaces over 5 feet from the toilet bowl.
90min
Airborne duration
Smaller particles remain suspended — and detectable — for up to 90 minutes after a single flush.
2×
Surface contamination
Open-lid flushing results in twice as many bacterial colonies on surrounding surfaces vs. closed-lid.
44%
Flush lid-up
44% of Americans flush with the lid up. 47% say it's because they didn't know the risk.

My approach

The lid shouldn't
be a choice.

Make closing the lid the default step, not an extra one.

How it works

Step 1
Step 2
Step 3
Step 4
01

Enter.

The lid is open by default, ready for the next user.

02

Trigger.

After use, the user triggers the button with their foot — no hands, no surfaces touched.

03

Close & flush.

The lid closes automatically. Only once sealed, the flush activates — containing the aerosol plume inside.

04

Reset.

After flushing, the lid reopens, ready for the next user.

How It Looks

Close and Flush Integration System Servo-driven hinge Automated lid closing Hall sensor Confirms lid fully sealed Flush button Triggers close + flush

Built. And it works.

Installation view

Details.

Servo-driven hinge
Servo-driven hinge

Two servos control the toilet lid and seat ring independently.

Hall sensor
Seat ring with Hall sensor

Confirms lid fully sealed before flush.

Seat button Flush button
Seat button · Flush button

102mm accessible size. Operable by foot or wheelchair.

In action.

Then came the making.

Building a working prototype meant solving each mechanical and electronic constraint from scratch.

Cardboard prototype

Early prototype. Cardboard looks-like model to test scale and lid geometry.

Electronics

Electronics. Servo, Hall sensor, and buttons wired to Arduino Uno.

Works-like model

Works-like model. A functional mock-up to validate servo angles and test the full user flow.

Custom hinge shaft

Custom hinge shaft. Designed and 3D printed to fit the servo inside the existing hinge geometry.

Structural modeling

Modeling. Full hinge assembly in Fusion 360. Servo housing, bearing seats, and lid attachment.

Assembly

Assembly. Fitting the 3D printed components together with the servo and hinge mechanism.

Five interventions.
One restroom.

Each product targets a different moment where hygiene fails.

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