Experimental Evaluation of a Source-Control Toilet System for Aerosol Suppression Using Ammonia (NH3) and Hydrogen Sulfide (H2S) Gases

IF 4.3 2区环境科学与生态学 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Indoor air Pub Date : 2026-03-31 DOI:10.1155/ina/6686313

Man-Gyu Song, Sumin Kim, Sang-Gyu Kim, Philip Kofie, Ju-Dong Jang

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引用次数: 0

Abstract

Background

Toilet flushing in public restrooms generates bioaerosols that may contain pathogenic microorganisms, posing potential risks for airborne infection transmission. Conventional control strategies such as ventilation and disinfection primarily function after contaminants have already dispersed, offering limited preventive efficacy.

objective

This study is aimed at scientifically verifying the effectiveness of a negative-pressure toilet system applying the source control principle, which captures and removes contaminants at the point of generation.

Methods

To simulate bioaerosol behavior, ammonia (NH₃) and hydrogen sulfide (H₂S) were used as surrogate gases due to their comparable aerodynamic properties. The performance of the Etish-D1st system was evaluated under the official testing protocols of the Korea Conformity Laboratories (KCL), focusing on odor gas removal efficiency, suction flow rate, and noise level under operating and nonoperating conditions.

Results

When the system was activated, NH₃ concentration inside the toilet was reduced to a nondetectable level (≤ 5 ppm) within 10 min, whereas nonoperating conditions reached up to 45 ppm. The mean suction flow rate was 114 mL/s, and the average noise level was 48 dB, indicating both high collection efficiency and environmental compatibility for public use.

Conclusions

The negative-pressure system effectively contained gaseous contaminants at the emission source, reducing their concentrations to below the 5-ppm detection limit and preventing measurable dispersion into the surrounding air. These findings provide a scientific foundation for active prevention in public health engineering. Future policy integration into the Public Restroom Act and Building Facility Standards, along with R&D and certification support, would strengthen institutional adoption. The Etish-D1st system presents an innovative sanitary technology with potential to enhance restroom hygiene and establish a new international standard for infection prevention infrastructure.

Abstract Image

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氨（NH3）和硫化氢（H2S）气体抑制气溶胶源控厕所系统的实验评价

背景：在公共厕所冲马桶会产生生物气溶胶，其中可能含有致病微生物，有可能通过空气传播感染。传统的控制策略，如通风和消毒，主要在污染物已经分散后发挥作用，预防效果有限。本研究旨在科学验证应用源控制原理的负压厕所系统的有效性，该系统在产生点捕获并去除污染物。方法采用氨（NH3）和硫化氢（H2S）作为替代气体，模拟生物气溶胶的行为，因为它们具有相似的气动特性。etish - d1系统的性能根据韩国合格实验室（KCL）的官方测试方案进行了评估，重点是在运行和非运行条件下的恶臭气体去除效率、吸入流量和噪音水平。结果系统启动后，厕所内NH3浓度在10 min内降至不可检测水平（≤5 ppm），而非运行状态下可达45 ppm。平均吸流量为114 mL/s，平均噪声为48 dB，表明收集效率高，适合公共使用。结论该负压系统有效地控制了排放源处的气态污染物，将其浓度降至5ppm以下的检测限值，并防止了可测量的向周围空气中的扩散。这些发现为公共卫生工程中的主动预防提供了科学依据。未来的政策整合到公共厕所法案和建筑设施标准中，以及研发和认证支持，将加强机构的采用。etish - d1系统是一种创新的卫生技术，具有提高厕所卫生和建立新的感染预防基础设施国际标准的潜力。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Indoor air 环境科学-工程：环境

CiteScore

10.80

自引率

10.30%

发文量

175

审稿时长

3 months

期刊介绍： The quality of the environment within buildings is a topic of major importance for public health. Indoor Air provides a location for reporting original research results in the broad area defined by the indoor environment of non-industrial buildings. An international journal with multidisciplinary content, Indoor Air publishes papers reflecting the broad categories of interest in this field: health effects; thermal comfort; monitoring and modelling; source characterization; ventilation and other environmental control techniques. The research results present the basic information to allow designers, building owners, and operators to provide a healthy and comfortable environment for building occupants, as well as giving medical practitioners information on how to deal with illnesses related to the indoor environment.