Improve Energy Installs Odorless, Infection-Preventing Portable Toilets 'ZoneZero' for Limited Time During Sannōsai Festival on June 13th to Support Comfortable Environment for Festival Staff and Mikoshi Bearers

Improve Energy Inc. (Headquarters: Osaka City, Osaka Prefecture; President and CEO: Nobuyuki Owari) will install two units of the "Wow?! No Odor?! Infection-Preventing Portable Toilet 'ZoneZero' Series" (hereinafter referred to as ZoneZero) on June 13, 2026, for a limited time, at a corner of Shimizu Corporation's headquarters premises, in coordination with relevant parties, coinciding with the "Sannōsai" festival, known as one of Japan's three major festivals. This initiative is positioned as an opportunity to provide a comfortable toilet environment for the bearers and staff supporting the festival, and simultaneously to communicate the importance of improving on-site working conditions, including toilets, to the construction industry, which is facing severe labor shortages and high turnover.

Supporting the Sannōsai, one of Japan's three major festivals, with a more comfortable environment for staff

The Sannōsai is a traditional festival that ranks among Japan's three major festivals, attracting many visitors during its period.

The Sannōsai is a historic festival that has continued since the Edo period as the annual festival of Hie Shrine in Tokyo, and is known as one of the "Three Great Festivals of Japan" alongside Kyoto's Gion Matsuri and Osaka's Tenjin Matsuri.

During the festival period, the central Tokyo area attracts many people, and the streets and surrounding areas are bustling with visitors coming to see the portable shrine procession and various rituals.

In such large-scale festivals and events, environmental improvements that support the comfort of staff are also important factors. Toilet facilities, in particular, are infrastructure directly linked to satisfaction, yet conventional portable toilets still carry a strong image of being "smelly," "dirty," and "difficult to use."

We aim to contribute to enhancing the value of the festival experience by providing a comfortable toilet environment that festival staff can use with peace of mind, even during the historic and traditional Sannōsai.

Eliminating challenges of portable toilets at outdoor events and improving comfort for festival operations staff

In recent years, interest in toilet environments has been growing for events such as fireworks festivals, music festivals, sports events, and local festivals. The larger the scale of the event, the longer the operational staff and visitors stay around the venue, making the convenience and hygiene of toilets crucial factors that influence the overall impression of the event.

However, traditional portable toilets have faced challenges such as:

● Discomfort due to odor

● Concerns about hygiene

● Insect intrusion

● Interior dirtiness

● Cleaning burden after use

We are developing ZoneZero with the concept of "changing the common perception of portable toilets" to solve these issues.

Equipped with proprietary technology aiming for "no odor"

ZoneZero is an infection-preventing portable toilet developed with consideration for user comfort and hygiene.

Key features are as follows:

■ Odor-preventing infection control technology (Patented technology "Odourless-Fi System")

Releases negative ions and low-concentration ozone into the interior and the waste tank to decompose and inactivate odor molecules, viruses, and bacteria.

It also considers the environment, aiming to suppress odor generation without using chemicals.

■ Spacious and comfortable interior (Meets Ministry of Land, Infrastructure, Transport and Tourism "Comfortable Toilet Recommended" standards)

Provides an interior space of 900mm x 1280mm.

As a mass-produced plastic portable toilet, each unit meets the Ministry of Land, Infrastructure, Transport and Tourism's "Comfortable Toilet Recommended" standards.

■ Equipped with automatic flushing system

Includes a non-contact automatic hand-washing station as standard equipment inside, made possible by the spacious interior.

The automatic flushing system is water-saving, using only 150cc of water per flush.

■ Industry-first* silicone flapper device

Prevents the backflow of odors and insects due to its high sealing performance.

Supports the maintenance of a comfortable indoor environment.

■ Large capacity 450L tank

Equipped with a waste tank approximately 1.5 times larger than conventional portable toilets.

Reduces the frequency of emptying, enabling stable operation even during long events.

■ Floor structure that can be washed entirely

Features a unique floor panel design where drainage during cleaning flows into the waste tank.

Allows for the entire interior to be washed, contributing to maintaining a hygienic environment.

*According to our research

Installation Overview

【Event Name】

Sannōsai

【Installation Date】

Saturday, June 13, 2026

【Installation Location】

A corner of Shimizu Corporation Headquarters (2-16-1 Kyobashi, Chuo-ku, Tokyo)

【Number of Units】

Two units of "Wow?! No Odor?! Infection-Preventing Portable Toilet 'ZoneZero' Series"

【Target Users】

Festival staff (e.g., Mikoshi bearers)

From outdoor events to construction sites: Addressing toilet challenges in outdoor environments

This installation is positioned not only to enhance the comfort of staff supporting the Sannōsai but also as an opportunity to showcase the potential for improving toilet environments for people working and supporting outdoor activities, such as at outdoor events and construction sites.

According to the Ministry of Land, Infrastructure, Transport and Tourism, the number of workers in the construction industry (average for Reiwa 6) is 4.77 million, a decrease of about 30% from its peak (Heisei 9), indicating a severe labor shortage. While those aged 55 and over account for 36.7% of the workforce, those aged 29 and under represent only 11.7%, showing a simultaneous progression of aging and a shortage of young talent. Securing and retaining young, female, and foreign workers is an urgent issue for the construction industry.

One of the factors hindering the recruitment and retention of such personnel is the toilet environment at construction sites. The impression of "odor" and "unhygienic conditions" can cause psychological stress to workers, potentially leading to decreased job satisfaction, lower retention rates, and ultimately, turnover. The Ministry of Land, Infrastructure, Transport and Tourism also promotes the spread of "comfortable toilets" as an important measure for improving working conditions, and major general contractors are increasingly recognizing the quality of toilet facilities as a factor influencing talent acquisition.

ZoneZero, with its "odorless" environment achieved through the patented "Odourless-Fi System" and its design that reduces cleaning and maintenance burdens, will transform the often-neglected toilet environment at work sites into a core element for "worker comfort" and "creating an attractive worksite." We aim not only to provide comfort to festival staff but also to contribute to improving working conditions in the construction industry and creating worksites where young and female workers can thrive.