Review on the generation, characteristics and control methods of indoor ozone pollution

Under the dual effects of outdoor ozone (O₃) pollution intrusion and indoor pollution source generation, the formation mechanism, characterization, prevention and control methods of indoor O₃ pollution have been one important scientific issue in the field of indoor air quality (IAQ) research. To have a systematic understanding of this issue, this study summarizes the trends and hotspots of indoor ozone pollution research, systematically reviews the sources, hazards, and characteristics of indoor ozone pollution and analyzes the different prevention and control methods of indoor ozone pollution, including active and passive ozone removal technologies. On this basis, the engineering applications of indoor ozone pollution prevention and control methods in residential, educational, and commercial scenarios are further discussed. Furthermore, the development trends and technical challenges of indoor ozone pollution prevention and control are pointed out. The development of efficient and low-cost ozone removal materials, the optimization of intelligent monitoring systems, and integrated pollution control strategies adapted to climate change should be focused on in the future, in order to provide healthier and safer indoor air environment. The insights could inform designers, engineers, and policymakers seeking to integrate ozone-responsive strategies into building ventilation, material selection, IAQ management, and air-cleaning systems.

1 Introduction

Ozone in the stratosphere absorbs the energy of ultraviolet photons and is protective of life on earth. However, ozone in the troposphere, especially in indoor environments, can adversely affect human health and even negatively impact socio-economics and productivity (Wang et al., 2022). Due to (i) the difficulty of accurately measuring ozone with past detection technologies, (ii) the public’s lack of awareness about the hazards of ozone, and (iii) the delayed effects of ozone on human health, indoor pollution research has focused more on substances such as PM2.5, formaldehyde, and carbon dioxide, while neglecting the harm of indoor ozone to humans. In recent years, ozone measurement technology has developed rapidly, such as Kernbach (2026) had proven an efficient electrochemical method for measuring ozone concentration through long-term field tests, this type of research has laid the foundation for subsequent research on indoor ozone pollution. More and more data show that the high concentration of outdoor ozone can enter indoor environment through ventilation, infiltration and other channels. Which causes indoor ozone concentration to be close to or even exceeding the health standard, bringing many pathological hazards to humans. Therefore, indoor ozone pollution has become a typical pollution problem that can’t be ignored.

Along with the development of industrialization and urbanization, ozone pollution is becoming increasingly serious, and has been attracted attention for its potential health and ecological hazards. Fadeyi (2015) reviewed the progress of indoor ozone research from 2000 to 2015,told us that high-performance buildings are a fundamental requirement for the 21st century. And called on us to properly consider ozone and its induced chemical products for their impact on human physiological, psychological and social conditions. Kong et al. (2022) observed that the negative health effects of ozone were not caused by other pollutants or precursors but by the nature of ozone itself, with higher ozone concentrations resulting in greater negative health effects. In addition, it has been found that ozone pollution exposure can induce cardiovascular disease. Therefore, it is a significant task in IAQ research field to grasp the formation mechanism and hazardous effects of indoor ozone pollution, and to construct its prevention and control methods.

In order to better grasp the latest research trend and research hotspots in indoor ozone pollution field, this study adopts CiteSpace to visualize the relevant literature in the Web of Science database in the past 10 years, seen in Figure 1. Figure 1 shows the “high intensity emergent keywords” for studies related to indoor ozone pollution from 2014 to 2024, listing the top 10 keywords with the highest emergent intensity. It can be found that the health risks of indoor ozone pollution have received a high level of attention in a given year. Secondly, “pollutants” and “oxidative stress” had significant emergence in 2015–2016 and 2015–2018, respectively, showing the importance of pollutants and oxidative stress in earlier studies. Meanwhile, “risk assessment” and “temperature” appeared in 2022–2024, indicating a gradual focus on pollutants and oxidative stress in recent years. In addition, from the perspective of timeline changes, keywords such as “ultrafine particles” and “black carbon” appeared more frequently in 2016–2021 and 2018–2019. Which reflects the attention paid by scholars in related fields to the synergistic effect of various indoor pollutants.

Figure 1

Figure 1. Indoor ozone pollution keywords highlighting: (a) Emergence Years; (b) Emergence Strength.[CiteSpace Workflow and Parameter Disclosure:TS = (“indoor ozone”OR“indoor O3” OR (“ozone” AND “indoor air quality”) OR (“ozone” AND “built environment”) OR (“ozone” AND “ventilation”)); Time slicing: 2014–2024, 1-year per slice; Node types: keywords, references; Selection criteria: g-index (k = 25).].

According to the following structure, shown in Figure 2, this study analyzes the sources and health effects of indoor ozone from its concentration change characteristics, reaction mechanism and chemical characteristics perspectives. Then, the existing ozone prevention and control technologies are summarized, and the advantages and disadvantages of active and passive control methods are compared. Thirdly, the engineering application of ozone control technology is discussed for different types of buildings. Finally, the key problems and development trends for future research are pointed out.

Figure 2

Figure 2. Content structure of this article.

2 Sources and regularity of indoor ozone pollution

On the one hand, the permeability of ozone is strong, and it is difficult to completely isolate ozone in the outside air. On the other hand, ozone is chemically active and it is easy to react with indoor Volatile Organic Compounds (VOCs) to generate more secondary pollutants. Therefore, the sources of indoor ozone pollution include two major parts: external infiltration (exogenous) and indoor generation (endogenous). The concentration distribution shows obvious characteristics, and will react violently with other indoor chemical substances, generating new types of pollutants. The following is described from three aspects: pollution source, concentration distribution law and ozone chemical reaction.

2.1 Sources of indoor ozone pollution

2.1.1 External sources

Atmospheric ozone concentration is significantly affected by seasonal and climatic factors, and ozone concentration is higher in summer under high temperature and strong ultraviolet irradiation. Outdoor ozone indirectly increases the indoor ozone level when it enters indoors through the ventilation system or building crevices, which is the primary source of indoor ozone. Zhong et al. (2017) analyzed the relationship between climate change and indoor ozone, and found that climate change directly affects atmospheric ozone concentration, while indoor ozone concentration depends largely on the ozone concentration around the building. Xu F. et al. (2023) measured indoor ozone concentration under different window opening conditions in 24 residential buildings in Nanjing, China. The data showed that the average outdoor ozone concentration under the test conditions was 68.2 μg/m³, the average indoor concentration when the window was closed was 21.2 μg/m³, and the average indoor concentration when the window was open was 35.3 μg/m³. From these results, it can be seen that the outdoor ozone concentration has a significant effect on the indoor ozone concentration.

2.1.2 Internal sources

In addition to external sources, some indoor devices generate ozone through high-voltage discharges or photochemical reactions and release it into indoor air during operation. Guo et al. (2019) conducted field sampling measurement and noted that the average ozone emission rate for ducted air purifiers, photocopying machines, laser printers, and other small devices was 62.8, 76.3, 4.6, 3.3, 0.8, and 0.4 mg per hour (mg/h), respectively. Ozone concentrations were significantly higher in environments where these devices are frequently used than in ordinary residential environments. Therefore, reducing the time and frequency of use of such equipment can help reduce indoor ozone concentration.

2.2 Indoor ozone concentration analysis

Factors affecting indoor ozone concentration include outdoor environmental infiltration, indoor equipment generation, chemical reactions, ventilation removal, purification technology removal and plant absorption, seen in Figure 3. The specific changes in indoor ozone concentration are shown in Equation 1:

$\frac{\mathrm{d}\left(O_3\right)}{\text{dt}}=G_{\text{in}}+G_{\text{dev}}+G_{chem}-L_{vent}-L_{tech}-L_{\text{abso}}(1)$

Figure 3

Figure 3. Gain and loss of indoor ozone.

There G_in represents the ozone infiltration from outdoor environment; G_dev is the ozone generated by the indoor equipment; G_chem represents the ozone produced by indoor chemical reaction; L_vent is the ozone removed by ventilation; L_{tech, purification} represents the ozone removed by technology removal; L_abso is the ozone absorbed by PRM materials.

Although the sources of indoor ozone have been identified, real-time monitoring of its concentration remains a significant challenge. Choi et al. (2023) developed a detection method utilizing o-dianisidine as a reaction reagent coated on a polydimethylsiloxane (PDMS) substrate, with a limit of detection of about 1.79 ppb, which is able to meet the indoor low concentration ozone. Indoor ozone concentrations at different measurement points are affected by a variety of factors. Nazaroff and Weschler (2022) concluded that outdoor ozone penetration is closely related to building parameters, mainly reflected in the following seven aspects: (i) ozone removal from mechanical ventilation systems, (ii) ozone permeability through the building envelope, (iii) the rate of air exchange, (iv) the rate of ozone loss from fixed indoor surfaces, (v) the rate of ozone loss from human occupants, (vi) ozone loss through homogeneous reaction with nitric oxide, and (vii) ozone loss through reaction with gas-phase organic matter.

In terms of temporal distribution, by observing the data from https://www.aqistudy.cn/. It is found that ozone concentrations are usually higher in summer and daytime than in winter and nighttime, directly leading to an increase in the infiltration of outdoor ozone. In terms of spatial distribution, Zhang et al. (Zhang et al., 2024) mentioned that ozone concentration increases with the rise of floors, which is due to the better air circulation in the upper floors of high-rise buildings, which makes it easy for outdoor ozone to infiltrate. Through the literature search (Nazaroff and Weschler, 2022; Mandin et al., 2017; Branco et al., 2015; Che et al., 2021; Uchiyama et al., 2015; Kalimeri et al., 2016; Jovanović et al., 2014; Nørgaard et al., 2014; Demirel et al., 2014; Othman et al., 2020; Barkjohn et al., 2021), the average indoor ozone concentrations of different types of buildings in some regions were summarized, as shown in Figure 4. It can be seen that the degree of indoor ozone pollution is different in different regions. This disparity is caused by differences in sampling locations of different samples, measurement seasons, recording methods, indoor ozone removal strategies, sample sizes, and other factors.

Figure 4

Figure 4. Indoor ozone concentrations in different types of buildings in selected areas. [Data comes from 11 related articles on science.direct.com.Reference (Nazaroff and Weschler, 2022; Mandin et al., 2017; Branco et al., 2015; Che et al., 2021; Uchiyama et al., 2015; Kalimeri et al., 2016; Jovanović et al., 2014; Nørgaard et al., 2014; Demirel et al., 2014; Othman et al., 2020; Barkjohn et al., 2021)].

2.3 Chemical reaction mapping of ozone

The physicochemical properties and molecular structure of ozone are fundamental to understanding its behavior in the air. The bond in the ozone molecule involves a resonance structure in which a double bond is formed between two oxygen atoms and a single bond is formed between the third oxygen atom and one of the oxygen atoms. Due to its strong oxidizing properties, indoor ozone can react with a wide range of VOCs to produce complex secondary pollutants, including aldehydes and ketones, which are harmful gasses, as shown in Figure 5.

Figure 5

Figure 5. Chemical reaction mapping of indoor ozone.

Ozone production involves two main precursors, VOCs and NOx. As mentioned in the papers by Weschler and Nazaroff (2023) and Rim et al. (2018), indoor ozone and the reaction by-products undergo a more complex chemical reaction on the surface of the human skin and surrounding environment, with 30%–55% of the ozone secondary reactions possibly being caused by human skin oils. In addition to human skin oils, complex ozone-related reactions can also occur on the surfaces of other materials indoors. Quarcoo et al. (2019) used a mass-balance indoor/outdoor ratio expression to model indoor ozone to simulate indoor particles of Secondary Organic Aerosol (SOA) generated by ozone-induced chemical reactions. Shen and Gao (2018) showed that chemicals contained in indoor materials react with ozone to generate SOA, and Hassan et al. (2025) found that the increase in ozone concentration raised the concentration of VOCs in air filters and the odor indoors. It is worth noting that chemical reactions are usually affected by temperature, humidity and air flow rate, but the strong oxidizing properties of ozone allow these reactions to take place at room temperature. The reaction products are further hydrolyzed with moisture in the air and slowly evaporate indoors over a long period of time, making them difficult to remove.

3 Study on the hazards of indoor ozone pollution

The hazards of ozone exposure to humans are related to the duration of exposure, the strength of the body’s immune system, and the secondary hazards of complex products, as shown in Table 1. This section provides an overview from four aspects of the hazards: (i) short-term exposure hazard; (ii) long-term exposure hazard; (iii) health risks to vulnerable populations, and (iv) the potential health effects of the secondary products of ozone.

Table 1

Table 1. Summary of indoor ozone hazards.

3.1 Health hazards of short-term exposure

Short-term exposure to high ozone concentrations can irritate the human respiratory system, leading to airway inflammation, airway allergic reactions, and other acute symptoms, even asthma. Regarding the period of high outdoor ozone concentration, Yue (2024) used large-scale population data analysis to propose that ozone-exposed groups have a significantly higher risk of lung health, especially among those who have frequent outdoor activities in summer. Verstraelen et al. (2024) carried out an in vitro study on the effects of ozone on the lungs of people exposed to ozone in a simulated indoor environment of ozone and limonene, etc. The results showed that ozone-induced oxidative products were significantly toxic to airway cells, short-term exposure to high ozone concentrations caused pronounced damage to airway epithelial cells, as evidenced by increased apoptosis and increased expression of inflammatory factors. Tan et al. (2024) analyzed ozone exposure at the cellular level, and found that short-term exposure may induce early cardiovascular injury, partly through oxidative protein damage and TGF-β₁ signaling. Woller et al. (2025) studied 25,083 venous thromboembolism (VTE) cases in Utah’s Wasatch and found that during the wildfire season, elevated ozone was associated with an increased odds of VTE at lag 1-day (OR, 1.05; 95% CI, 1.00–1.10; P = 0.0545), mean 3-day lagged average (OR, 1.06; 95% CI, 1.00–1.13; P = 0.05), and mean 7-day lagged average (OR, 1.09; 95% CI, 1.01–1.18; P = 0.037). Therefore, short-term exposure to high concentrations of ozone can lead to a variety of health problems, prevention and control of ozone pollution is important for the public to prevent cardiovascular risk early.

3.2 Health hazards of long-term exposure

Compared to short-term exposure, long-term exposure to low-level ozone is more difficult to detect, but the resulting health hazards cannot be ignored. Zhong et al. (2017) tracked and analyzed the health of different populations in low-level ozone environments, and found that long-term exposure to low-level ozone can cause chronic damage to multiple systems, exacerbating the risk of lung function decline and chronic respiratory disease. He et al. (He et al., 2025) analyzed the clinical data, and the results showed that continuous exposure to an indoor environment with ozone concentrations of 29 ± 13 ppb for 24 h led to a 1% (0.3%–1.6%) decrease in FVC and a 0.8% (0.2%–1.5%) decrease in FEV₁ in healthy adults. Li et al. (2024) analyzed the relationship between ozone exposure and cardiorespiratory fitness by monitoring indoor ozone concentrations during sleep (mean 20.3 μg/m³) and repeated measurements of lung function indices, heart rate variability (HRV) in 81 healthy adults aged 18–28 years. The relationship between ozone exposure and cardiorespiratory function was found to be significantly reduced by ozone exposure (e.g., FEF25-75 decreased by 9.60%). Shi et al. (2024), purposively recruited 32,541 males aged 22 and 65 and used generalized linear models to evaluate the relationship between ozone exposure and sperm quality parameters. The study results suggest that ozone may be a risk factor for reduced sperm quality in men. Rodrigu et al. (2024) pointed out that long-term ozone exposure induced oxidative damage in the nervous system. Following this work, Zhang et al. (2025) focused on the mechanism of action of ozone, and pointed out that ozone affected intercellular signaling, which results in central nervous system disorders (e.g., ischemic stroke). In summary, long-term exposure to low concentrations of ozone can cause chronic damage to various bodily functions that is difficult to detect, and its obvious delayed effects often lead people to overlook this harm.

3.3 Health risks for vulnerable populations

People with relatively low immunity, such as children and the elderly, are highly sensitive to ozone pollution, and these populations tend to exhibit more severe health risks. Yen et al. (2020) demonstrates that prolonged exposure of children to indoor environments with ozone concentrations exceeding 10 ppb may cause irreversible respiratory system developmental damage. Liu et al. (2021) recruited 46 healthy children aged 11–14 and monitored the ozone concentration in the classroom in real time, analyzing the children’s metabolic characteristics. The results showed that ozone exposure (average concentration 8.7 ± 6.6 ppb) caused significant changes in nine metabolites in the children’s urine, such as abnormalities in amino acid metabolism and bile acid secretion. Due to the low immunity of the elderly, ozone exposure is associated with higher blood pressure, increased cardiac load, and increased incidence of cardiovascular disease. Qu et al. (2023) found that for every 10 μg/m³ increase in ozone concentration, serum brain-derived neurotrophic factor (BDNF) and neurofilament light chain (NfL) increased by 74% and 197%, respectively, in 34 people with an average age of 63.7. It can be seen that vulnerable populations face more severe health risks when exposed to ozone pollution, therefore, they should pay more attention to prevent indoor ozone pollution and live in an environment with better IAQ indicators.

3.4 Potential hazards of secondary reaction products

In addition to the direct health hazards associated with indoor ozone pollution, the indirect effects of secondary reaction products (aldehydes, ketones, etc.) resulting from the reaction of indoor ozone with indoor wood paneling and cleaning agents should not be underestimated (Xu J. et al., 2023; Xue et al., 2022). Waring and Wells (2015) employed a time-averaged equation based on Monte Carlo-driven modeling effort and found that ozone participates in complex chemical reactions to generate VOCs in typical residential buildings. Shen and Gao (2018) investigated the heterogeneous reaction of ozone with indoor surface materials (e.g., wall paints) and found that the chemicals contained in these materials react with ozone secondarily to generate SOA, which further contributes to the deterioration of IAQ. In addition to the secondary pollutants already summarized above, ozone in indoor environments will certainly generate some potential harmful substances that have not yet been discovered. These substances constantly threaten people’s health and require further in-depth research by scholars.

4 Prevention and control methods of indoor ozone pollution

Indoor ozone pollution prevention and control methods are endless, can be summarized probably can be divided into active, passive and composite control strategy three categories. The following will be respectively from the specific technical means of these prevention and control methods, the application effect and applicability will be analyzed, shown in Table 2.

Table 2

Table 2. Comparative analysis of different prevention and control methods.

4.1 Active control methods

Active ozone removal methods are those that actively remove indoor ozone through external equipment or energy inputs, and include two broad categories: the use of purification technologies and the optimization of ventilation strategies. These methods are generally more efficient and can quickly reduce indoor ozone concentrations, and are suitable for locations with high ozone concentrations or where rapid ozone removal is required in a short period of time.

4.1.1 Air purification technology

Some purification devices are able to capture or decompose ozone molecules during air circulation. Namdari et al. (2021) and Khararood et al. (2022) analyzed a wide range of purification devices, and in total concluded that (i) air purifiers with HEPA filters, (ii) activated charcoal, (iii) photocatalytic filtration systems, as well as (iv) electrostatic filtration and ultraviolet decomposition functioned air treatment technologies are capable of removing indoor ozone quickly and efficiently. Some new technologies can also remove indoor ozone. Xu et al. (2018) found that ozone removal devices containing nanoporous TiO₂ films and Mn-Fe catalysts were able to reduce ozone content from 250 to 75 ppb. Duan et al. (2024) found that manganese oxide (MnOx)-based catalysts could decompose ozone into oxygen at room temperature without generating a large number of by-products through comparative studies. These approaches are certainly effective, but they require energy consumption, have high equipment maintenance costs, and some may produce other by-products during operation.

4.1.2 Rational ventilation strategies

Reasonable design of ventilation strategies and regular window opening can help to dilute indoor ozone, optimizing the filtration system when ventilating can improve the quality of the supplied air. Coffaro and Weisel (2022) analyzed the reaction and products of squalene and ozone, and Wang and Chen (2016) established the theoretical model for the chemical reaction between ozone and squalene on the surface of the human body. The results of the study showed that, under replacement ventilation, increasing the air exchange rate is conducive to reducing exposure to ozone and its secondary pollutants. Ben-David and Waring (2018) investigated the effects of ventilation and filtration on PM2.5 and ozone exposure of office buildings in the U.S. Analysis of the differences showed that ventilation and filtration are complementary, the use of high-efficiency filters can mitigate the negative impacts of ventilation, and a higher ventilation rate can improve the filtration efficiency. It can reasonably be inferred that adding filtration during ventilation can reduce the ozone concentration in the fresh air entering indoors, preventing high concentrations of outdoor ozone from entering the interior. In fact, in addition to the above methods, the low ozone concentration at night can also be used for air exchange, which can also reduce the accumulation of ozone during the day.

4.2 Passive control methods

Passive ozone removal methods are those that do not require an external energy input and rely on the properties of the materials themselves to reduce ozone concentrations, usually through the selection of special decorative materials, or houseplants. Passive methods are usually energy-neutral, low-cost, suitable for long-term use and environmentally friendly, but are slow to remove ozone and are suitable for relatively low indoor ozone concentrations or as a means of routine maintenance.

4.2.1 Ozone removal by PRM settling

Eco-friendly furniture, coatings, and paints have low VOC emissions, which can effectively reduce the formation of indoor ozone through chemical processes. Moreover, there are even materials that can passively remove ozone. Darling et al. (2016) presented the idea that Passive Removal Materials (PRMs) have a certain ozone-removal potential without the formation of a large number of harmful reaction products. Jing et al. (2022a) found that the ozone-removal ability of PRMs was correlated with the material area, migration-limited deposition rate, air change rate, and so on. Ye et al. (2020) and Ranesi et al. (2024) analyzed the deposition of ozone on seven common indoor materials and the effectiveness of eight paints in reducing ozone concentration when applied to indoor walls and ceilings, respectively. The results showed that the deposition rate of ozone varied among different materials, with the clay-based stucco and gypsum stucco with the incorporation of tree bark showing the best ozone removal activity. In addition to conventional building materials and furniture, Jiang et al. (2022) measured the ozone removal and ozone deposition rate of fine coffee powder to be 58.5% and 0.62 cm/s, respectively, which implies that the use of similar hydrocarbon materials for IAQ control is also feasible.

4.2.2 Indoor plant applications

Plants have a relatively limited effect on ozone removal, but have a complementary role as an energy-free green means. Abbass et al. (2017) studied the effect of five indoor plants (Peace Lily, Ficus, Caribbean Begonia, Tropical Calla Lily, and Golden Greenery) on ozone removal, and the results showed that all of these plants were able to settle indoor ozone more or less efficiently, with a settlement rate of between 0.5 and 5.5 m/h. However, the effectiveness of ozone removal is limited by plant species, indoor environmental conditions, and it is usually more effective at removing low concentrations of ozone.

4.3 Compound control methods

4.3.1 Ventilated coupled PRM

Active ozone removal technology is highly efficient, while passive ozone removal technology is more environmentally friendly and cost-effective. Combining the two is a good option for removing indoor ozone. Gall and Rim (2018) tested the effect of surface quality accumulation on ozone surface deposition by deploying clean borosilicate glass plates in two indoor environments: a mechanically ventilated (MV) office and a naturally ventilated (NV) residence, both located in Singapore. The test results show that the ozone removal rates before and after PRM material deployment were (0.06–0.74) × 10^–6 and (0.15–1.2) × 10^–6, respectively. Removal rate of 4.3 nmol O₃/mg for the NV residence and 2.4 nmol O₃/mg for the MV office. These findings demonstrate that integrating active and passive ozone removal strategies not only enhances overall removal efficiency but also improves system robustness across diverse ventilation conditions, offering a more comprehensive and stable approach for indoor ozone mitigation.

4.3.2 Synergistic control of PM2.5 and ozone

Synergistic prevention and control of different types of pollutants can reduce invisible and hard-to-detect ozone generation pathways. Hong et al. (2019) made several suggestions on synergistic control of PM2.5 and ozone pollution in the atmosphere. Kong et al. (2024) pointed out that, the implementation of a multipollutant emission reduction control strategy aimed at the prevention and control of PM2.5 and ozone pollution is the only means to realize the coordinated control of PM2.5 and ozone. Xu et al. (2025) proposed a composite fiber material based on microbial carbon coating (MBC@PET) for the efficient removal of indoor PM2.5 and ozone, with an ozone removal rate of up to 91.42%. Through the synergistic design of physical adsorption and chemical decomposition of microbial charcoal and the composite material, the efficient removal of indoor ozone was achieved, which provides a new idea for the green air purification technology.

5 Engineering applications of prevention and control methods

The prevention and control of indoor ozone pollution have their own needs in different types of building environments. The following three common building types, namely, residential, educational, and commercial, are introduced to introduce the application of ozone control engineering in different environments, with an emphasis on the prevention and control strategies and their implementation effects that are suitable for each type of building.

5.1 Applications for residential type buildings

Ozone prevention and control in residential buildings should emphasize the rational design of ventilation systems and careful selection of decorative materials in order to provide a comfortable environment while reducing the risk of pollution. Ma et al. (2023) focused on typical envelope airflow paths used in homes in the Philadelphia area of the United States, and indoor ozone prediction models based on inputs from the environmental investigations can be effective in predicting. Predicting ozone concentrations during the architectural design phase allows for the early development of control strategies, thereby improving and creating a healthy living environment. Jing et al. (2022b) found that the increase in ozone deposition rate will cause more ozone to be removed by indoor surfaces, thus reducing indoor ozone concentration, which is very suitable for residential buildings. The selection of environmentally friendly materials with ozone adsorption or decomposition ability, such as activated carbon coatings and titanium dioxide catalysts, can effectively reduce ozone content in the home environment and safeguard the health of occupants. This passive prevention and control method not only does not produce more pollutants, but also improves IAQ indicators by decomposing ozone.

5.2 Applications for educational type buildings

In educational buildings such as kindergartens, school buildings, and libraries, where IAQ is critical to the health of children and adolescents, low ozone-emitting equipment and materials should be prioritized. Salonen et al. (2018) reviewed dozens of papers and calculated median ozone concentrations in school and office environments to be 8.50 μg/m3 (mean 0.8 μg/m³-114 μg/m³) and 9.04 μg/m³ (mean 0–96.8 μg/m³), respectively, indicating a risk of exceeding the WHO 8-h guideline value (100 μg/m³). Effective ozone control in educational buildings can be achieved by (i) optimizing ventilation schedules to avoid outdoor ozone peaks, (ii) isolating printers or photocopiers in dedicated exhausted rooms, and (iii) applying passive removal materials (PRMs) such as manganese oxide–based coatings, activated-carbon-enhanced wall materials, or low-VOC treated wood. These methods can sustainably remove ozone without increasing energy consumption and are particularly suitable for classrooms and corridors.

5.3 Applications for commercial type buildings

In commercial spaces such as shopping malls, hotels, and restaurants, ozone prevention and control needs to take into account the characteristics of heavy foot traffic and diverse equipment. Tang et al. (2022) evaluated the ozone removal performance of 14 commercially available air purification devices used in building ventilation systems, which retained their efficiency over long periods of time in the building ventilation system. In commercial buildings, ozone mitigation can be enhanced through ventilation–filtration coupling strategies using advanced media such as MERV 13+ activated carbon. Optimize airflow distribution to limit ozone intrusion, incorporating catalytic ozone decomposition units—including MnO_x catalysts, TiO₂–VUV photocatalytic modules—into HVAC systems for high single-pass removal efficiency. Apply PRM coatings, catalytic panels near diffusers, and airflow optimization (e.g., CFD-based design) to reduce ozone accumulation in atriums, corridors, and other large open spaces. These methods can significantly reduce ozone levels, enhance customer experience, and are ideal for commercial buildings.

6 Conclusion

The rising demand for the prevention and control of indoor ozone pollution has led to the emergence of new technologies and methods, which shows a broad development prospect from the development of advanced functional materials, intelligent monitoring and control systems, synergistic cross-pollutant management, and so on. This paper summarizes the sources of indoor ozone pollution, health hazards, concentration distribution characteristics, and the application of its prevention and control technologies. Synthesizing the existing literature and research results, the following main conclusions are drawn:

Firstly, indoor ozone pollution comes from a variety of sources, including the infiltration of outdoor ozone and the generation of indoor equipment. Ozone in the indoor environment not only poses a direct hazard to the respiratory, cardiovascular and nervous systems, but also generates potential secondary pollutants by reacting with other chemicals, exacerbating the threat to human health.

Secondly, ozone pollution prevention and control technologies have made significant progress in recent years, including active, passive and combined control methods. Active methods include air purification techniques and optimization of ventilation strategies; passive methods include the use of PRM materials with ozone decomposition or adsorption capacity and the use of indoor plants to absorb ozone.

However, there are still a number of challenges and scientific issues that need to be addressed for indoor ozone prevention and control. How to make the new PRM materials play an efficient ozone removal role while meeting the economic requirements is a key direction for future research; the Internet of Things (IoT)-driven air quality monitoring and control technology under the premise of disciplinary crossover is facing technical problems such as cost, data compatibility and system stability. Therefore, future research on indoor ozone pollution shows the following two trends:

On the one hand, the development of advanced nanomaterials and composite functional coatings with efficient ozone decomposition ability has been a major research focus in recent years. On the other hand, an intelligent ozone monitoring device based on the IoT needs to be developed to track indoor ozone levels in real-time and promptly detect potential hazards. Of course, further research on indoor ozone prevention and control technology relies on government policy support, and synergy between academia and industry to create a healthier, safer, and higher IAQ level living environment. It is hoped that relevant scholars will further study the above issues that need to be resolved in order to more comprehensively address the health threats posed by indoor ozone pollution.

Author contributions

JW: Writing – original draft, Writing – review and editing. QW: Investigation, Writing – original draft, Formal Analysis. TW: Writing – original draft, Methodology, Data curation.

Funding

The author(s) declared that financial support was received for this work and/or its publication. The National Natural Science Foundation of China under Grant No. 51308361 and the Key Research and Development Program of Sichuan Province Grant No. 2022YFG0138, No. 2020YFN0016.

Conflict of interest

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Generative AI statement

The author(s) declared that generative AI was not used in the creation of this manuscript.

Any alternative text (alt text) provided alongside figures in this article has been generated by Frontiers with the support of artificial intelligence and reasonable efforts have been made to ensure accuracy, including review by the authors wherever possible. If you identify any issues, please contact us.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

References

Abbass, O. A., Sailor, D. J., and Gall, E. T. (2017). Effectiveness of indoor plants for passive removal of indoor ozone. Build. Environ. 119, 62–70. doi:10.1016/j.buildenv.2017.04.007

CrossRef Full Text | Google Scholar

Barkjohn, K. K., Norris, C., Cui, X., Fang, L., Zheng, T., Schauer, J. J., et al. (2021). Real-time measurements of PM_2.5 and ozone to assess the effectiveness of residential indoor air filtration in shanghai homes. Indoor Air 31 (1), 74–87. doi:10.1111/ina.12716

PubMed Abstract | CrossRef Full Text | Google Scholar

Ben-David, T., and Waring, M. S. (2018). Interplay of ventilation and filtration: differential analysis of cost function combining energy use and indoor exposure to PM 2.5 and ozone. Build. Environ. 128, 320–335. doi:10.1016/j.buildenv.2017.10.025

CrossRef Full Text | Google Scholar

Branco, PTBS, Nunes, R. A. O., Alvim-Ferraz, M. C. M., Martins, F. G., and Sousa, S. I. V. (2015). Children’s exposure to indoor air in urban nurseries – part II: gaseous pollutants’ assessment. Environ. Res. 142, 662–670. doi:10.1016/j.envres.2015.08.026

PubMed Abstract | CrossRef Full Text | Google Scholar

Che, W., Li, A. T. Y., Frey, H. C., Tang, K. T. J., Sun, L., Wei, P., et al. (2021). Factors affecting variability in gaseous and particle microenvironmental air pollutant concentrations in Hong Kong primary and secondary schools. Indoor Air 31 (1), 170–187. doi:10.1111/ina.12725

PubMed Abstract | CrossRef Full Text | Google Scholar

Choi, H., Seo, J. H., and Weon, S. (2023). Visualizing indoor ozone exposures via o-dianisidine based colorimetric passive sampler. J. Hazard Mater 460, 132510. doi:10.1016/j.jhazmat.2023.132510

PubMed Abstract | CrossRef Full Text | Google Scholar

Coffaro, B., and Weisel, C. P. (2022). Reactions and products of squalene and ozone: a review. Environ. Sci. Technol. 56 (12), 7396–7411. doi:10.1021/acs.est.1c07611

PubMed Abstract | CrossRef Full Text | Google Scholar

Darling, E., Morrison, G. C., and Corsi, R. L. (2016). Passive removal materials for indoor ozone control. Build. Environ. 106, 33–44. doi:10.1016/j.buildenv.2016.06.018

CrossRef Full Text | Google Scholar

Demirel, G., Özden, Ö., Döğeroğlu, T., and Gaga, E. O. (2014). Personal exposure of primary school children to BTEX, NO2 and ozone in eskişehir, Turkey: relationship with indoor/outdoor concentrations and risk assessment. Sci. Total Environ. 473–474, 537–548. doi:10.1016/j.scitotenv.2013.12.034

PubMed Abstract | CrossRef Full Text | Google Scholar

Duan, W., Tang, K., Zhao, L., Tian, Z., Wang, J., Hu, Y., et al. (2024). MnOx nanoparticle-loaded polyacrylonitrile fibers for efficient catalytic ozonation of toluene. Atmos. Pollut. Res. 15 (5), 102079. doi:10.1016/j.apr.2024.102079

CrossRef Full Text | Google Scholar

Fadeyi, M. O. (2015). Ozone in indoor environments: research progress in the past 15 years. Sustain. Cities Soc. 18, 78–94. doi:10.1016/j.scs.2015.05.011

CrossRef Full Text | Google Scholar

Gall, E. T., and Rim, D. (2018). Mass accretion and ozone reactivity of idealized indoor surfaces in mechanically or naturally ventilated indoor environments. Build. Environ. 138, 89–97. doi:10.1016/j.buildenv.2018.04.030

CrossRef Full Text | Google Scholar

Guo, C., Gao, Z., and Shen, J. (2019). Emission rates of indoor ozone emission devices: a literature review. Build. Environ. 158, 302–318. doi:10.1016/j.buildenv.2019.05.024

CrossRef Full Text | Google Scholar

Hassan, M. A., Liu, J., Jiang, J., Faheem, M., Zhang, M., and Yao, M. (2025). Elevated volatile organic compounds and odorant emissions from used air filters due to ozone exposure. Build. Environ. 275, 112826. doi:10.1016/j.buildenv.2025.112826

CrossRef Full Text | Google Scholar

He, L., Hao, Z., Weschler, C. J., Li, F., Zhang, Y., and Zhang, J. J. (2025). Indoor ozone reaction products: contributors to the respiratory health effects associated with low-level outdoor ozone. Atmos. Environ. 340, 120920. doi:10.1016/j.atmosenv.2024.120920

CrossRef Full Text | Google Scholar

Hong, L., Liang, P., Bi, F., Ling, L., Bao, J., and Junling, L. (2019). Strategy of coordinated control of PM2. 5 and ozone in China. Research of environmental sciences. Res. Environ. Sci. 32 (10), 1763–1778.

Google Scholar

Jiang, E. Y., and Wen, T. Y. (2022). “Indoor ozone removal and deposition using unactivated solid and liquid coffee. PLOS One 17 e0273188. doi:10.1371/journal.pone.0273188

PubMed Abstract | CrossRef Full Text | Google Scholar

Jing, L., and Wang, J. (2022a). Study on indoor ozone removal by PRM under the influence of typical factors. E3S Web Conf., 356, 5037. doi:10.1051/e3sconf/202235605037

CrossRef Full Text | Google Scholar

Jing, L., and Wang, J. (2022b). Characteristics of indoor ozone pollution in residential buildings based on outdoor air pollution. E3S Web Conf. 356, 5033. doi:10.1051/e3sconf/202235605033

CrossRef Full Text | Google Scholar

Jovanović, M., Vučićević, B., Turanjanin, V., Živković, M., and Spasojević, V. (2014). Investigation of indoor and outdoor air quality of the classrooms at a school in Serbia. Energy 77, 42–48. doi:10.1016/j.energy.2014.03.080

CrossRef Full Text | Google Scholar

Kalimeri, K. K., Saraga, D. E., Lazaridis, V. D., Legkas, N. A., Missia, D. A., Tolis, E. I., et al. (2016). Indoor air quality investigation of the school environment and estimated health risks: two-season measurements in primary schools in kozani, Greece. Atmos. Pollut. Res. 7 (6), 1128–1142. doi:10.1016/j.apr.2016.07.002

CrossRef Full Text | Google Scholar

Kernbach, S. (2026). In-situ biological ozone detection by measuring electrochemical impedances of plant tissues. Bioelectrochemistry 168, 109088. doi:10.1016/j.bioelechem.2025.109088

PubMed Abstract | CrossRef Full Text | Google Scholar

Khararoodi, M. G., Haghighat, F., and Lee, C. S. (2022). Removal of indoor air ozone using carbon-based filters: systematic development and validation of a predictive model. Build. Environ. 219, 109157. doi:10.1016/j.buildenv.2022.109157

CrossRef Full Text | Google Scholar

Kong, D., Liang, J., and Liu, C. (2022). Invisible enemy: the health impact of ozone. China Econ. Rev. 72, 101760. doi:10.1016/j.chieco.2022.101760

CrossRef Full Text | Google Scholar

Kong, L., Song, M., Li, X., Liu, Y., Lu, S., Zeng, L., et al. (2024). Analysis of China’s PM2.5 and ozone coordinated control strategy based on the observation data from 2015 to 2020. J. Environ. Sci. 138, 385–394. doi:10.1016/j.jes.2023.03.030

PubMed Abstract | CrossRef Full Text | Google Scholar

Li, L., Zhang, W., Liu, S., Wang, W., Ji, X., Zhao, Y., et al. (2024). Cardiorespiratory effects of indoor ozone exposure during sleep and the influencing factors: a prospective study among adults in China. Sci. Total Environ. 924, 171561. doi:10.1016/j.scitotenv.2024.171561

PubMed Abstract | CrossRef Full Text | Google Scholar

Liu, S., Huang, Q., Zhang, X., Dong, W., Zhang, W., Wu, S., et al. (2021). Cardiorespiratory effects of indoor ozone exposure associated with changes in metabolic profiles among children: a repeated-measure panel study. Innovation 2 (1), 100087. doi:10.1016/j.xinn.2021.100087

PubMed Abstract | CrossRef Full Text | Google Scholar

Ma, N., Zhang, Q., and Braham, W. W. (2023). Rethinking building envelope design: machine learning approaches to evaluate its impact on indoor ozone exposures. J. Phys. Conf. Ser. 2600 (10), 102002. doi:10.1088/1742-6596/2600/10/102002

CrossRef Full Text | Google Scholar

Mandin, C., Trantallidi, M., Cattaneo, A., Canha, N., Mihucz, V. G., Szigeti, T., et al. (2017). Assessment of indoor air quality in office buildings across Europe – the OFFICAIR study. Sci. Total Environ. 579, 169–178. doi:10.1016/j.scitotenv.2016.10.238

PubMed Abstract | CrossRef Full Text | Google Scholar

Namdari, M., Lee, C. S., and Haghighat, F. (2021). Active ozone removal technologies for a safe indoor environment: a comprehensive review. Build. Environ. 187, 107370. doi:10.1016/j.buildenv.2020.107370

CrossRef Full Text | Google Scholar

Nazaroff, W. W., and Weschler, C. J. (2022). Indoor ozone: concentrations and influencing factors. Indoor Air 32 (1), e12942. doi:10.1111/ina.12942

PubMed Abstract | CrossRef Full Text | Google Scholar

Nørgaard, A. W., Kofoed-Sørensen, V., Mandin, C., Ventura, G., Mabilia, R., Perreca, E., et al. (2014). Ozone-initiated terpene reaction products in five european offices: replacement of a floor cleaning agent. Environ. Sci. Technol. 48 (22), 13331–13339. doi:10.1021/es504106j

PubMed Abstract | CrossRef Full Text | Google Scholar

Othman, M., Latif, M. T., Yee, C. Z., Norshariffudin, L. K., Azhari, A., Halim, N. D. A., et al. (2020). PM2.5 and ozone in office environments and their potential impact on human health. Ecotoxicol. Environ. Saf. 194, 110432. doi:10.1016/j.ecoenv.2020.110432

PubMed Abstract | CrossRef Full Text | Google Scholar

Qu, R., Sun, B., Jiang, J., An, Z., Li, J., Wu, H., et al. (2023). Short-term ozone exposure and serum neural damage biomarkers in healthy elderly adults: evidence from a panel study. Sci. Total Environ. 905, 167209. doi:10.1016/j.scitotenv.2023.167209

PubMed Abstract | CrossRef Full Text | Google Scholar

Quarcoo, M. A., Strickland, P. O., and Shendell, D. G. (2019). Indoor ozone estimation from outdoor ozone and LBNL relocatable classroom study data. Atmos. Environ. 213, 491–498. doi:10.1016/j.atmosenv.2019.06.036

CrossRef Full Text | Google Scholar

Ranesi, A., Faria, P., Veiga, M. R., and Gall, E. T. (2024). Eco-efficient coatings for healthy indoors: ozone deposition velocities, primary and secondary emissions. Build. Environ. 254, 111306. doi:10.1016/j.buildenv.2024.111306

CrossRef Full Text | Google Scholar

Rim, D., Gall, E. T., Ananth, S., and Won, Y. (2018). Ozone reaction with human surfaces: influences of surface reaction probability and indoor air flow condition. Build. Environ. 130, 40–48. doi:10.1016/j.buildenv.2017.12.012

CrossRef Full Text | Google Scholar

Rodriguez, P., López-Landa, A., Romo-Parra, H., Rubio-Osornio, M., and Rubio, C. (2024). Unraveling the ozone impact and oxidative stress on the nervous system. Toxicology 509, 153973. doi:10.1016/j.tox.2024.153973

PubMed Abstract | CrossRef Full Text | Google Scholar

Salonen, H., Salthammer, T., and Morawska, L. (2018). Human exposure to ozone in school and office indoor environments. Environ. Int. 119, 503–514. doi:10.1016/j.envint.2018.07.012

PubMed Abstract | CrossRef Full Text | Google Scholar

Shen, J., and Gao, Z. (2018). Ozone removal on building material surface: a literature review. Build. Environ. 134, 205–217. doi:10.1016/j.buildenv.2018.02.046

CrossRef Full Text | Google Scholar

Shi, Y., Zhang, Y., Yuan, K., Han, Z., Zhao, S., Zhang, Z., et al. (2024). Exposure to ambient ozone and sperm quality among adult men in China. Ecotoxicol. Environ. Saf. 283, 116753. doi:10.1016/j.ecoenv.2024.116753

PubMed Abstract | CrossRef Full Text | Google Scholar

Tan, Q., Zhou, M., You, X., Ma, J., Ye, Z., Shi, W., et al. (2024). Association of ambient ozone exposure with early cardiovascular damage among general urban adults: a repeated-measures cohort study in China. Sci. Total Environ. 957, 177380. doi:10.1016/j.scitotenv.2024.177380

PubMed Abstract | CrossRef Full Text | Google Scholar

Tang, M., Siegel, J. A., Corsi, R. L., and Novoselac, A. (2022). Evaluation of ozone removal devices applied in ventilation systems. Build. Environ. 225, 109582. doi:10.1016/j.buildenv.2022.109582

CrossRef Full Text | Google Scholar

Uchiyama, S., Tomizawa, T., Tokoro, A., Aoki, M., Hishiki, M., Yamada, T., et al. (2015). Gaseous chemical compounds in indoor and outdoor air of 602 houses throughout Japan in winter and summer. Environ. Res. 137, 364–372. doi:10.1016/j.envres.2014.12.005

PubMed Abstract | CrossRef Full Text | Google Scholar

Verstraelen, S., Maes, F., Jacobs, A., Remy, S., Frijns, E., Goelen, E., et al. (2024). In vitro assessment of acute airway effects from real-life mixtures of ozone-initiated oxidation products of limonene and printer exhaust. J. Environ. Sci. Health A 59 (8), 403–419. doi:10.1080/10934529.2024.2406113

PubMed Abstract | CrossRef Full Text | Google Scholar

Wang, J., and Chen, Y. (2016). Concentration characteristics of ozone and product for indoor occupant surface chemical reaction under displacement ventilation. Energy Build. 130, 378–387. doi:10.1016/j.enbuild.2016.08.065

CrossRef Full Text | Google Scholar

Wang, C., Lin, Q., and Qiu, Y. (2022). Productivity loss amid invisible pollution. J. Environ. Econ. Manage 112, 102638. doi:10.1016/j.jeem.2022.102638

CrossRef Full Text | Google Scholar

Waring, M. S., and Wells, J. R. (2015). Volatile organic compound conversion by ozone, hydroxyl radicals, and nitrate radicals in residential indoor air: magnitudes and impacts of oxidant sources. Atmos. Environ. 106, 382–391. doi:10.1016/j.atmosenv.2014.06.062

PubMed Abstract | CrossRef Full Text | Google Scholar

Weschler, C. J., and Nazaroff, W. W. (2023). Human skin oil: a major ozone reactant indoors. Environ. Sci. Atmos. 3 (4), 640–661. doi:10.1039/d3ea00008g

CrossRef Full Text | Google Scholar

Woller, S. C., Stevens, S. M., Bledsoe, J. R., Bride, D., Lloyd, J. F., Butler, A., et al. (2025). Risk of venous thromboembolism associated with short-term exposure to fine particulate matter (PM2.5) and ozone air pollution. Res. Pract. Thromb. Haemost. 9 (7), 103226. doi:10.1016/j.rpth.2025.103226

PubMed Abstract | CrossRef Full Text | Google Scholar

Xu, T., Zheng, H., and Zhang, P. (2018). Performance of an innovative VUV-PCO purifier with nanoporous TiO2 film for simultaneous elimination of VOCs and by-product ozone in indoor air. Build. Environ. 142, 379–387. doi:10.1016/j.buildenv.2018.06.047

CrossRef Full Text | Google Scholar

Xu, F., Shen, J., and Gao, Z. (2023). A field measurement study of the effects of outdoor pollutants and room volumes on indoor fine particle and ozone concentrations. J. Build. Eng. 78, 107615. doi:10.1016/j.jobe.2023.107615

CrossRef Full Text | Google Scholar

Xu, J., Deng, H., Wang, Y., Li, P., Zeng, J., Pang, H., et al. (2023). Heterogeneous chemistry of ozone with floor cleaning agent: implications of secondary VOCs in the indoor environment. Sci. Total Environ. 862, 160867. doi:10.1016/j.scitotenv.2022.160867

PubMed Abstract | CrossRef Full Text | Google Scholar

Xu, J., Xie, Y., Han, W., Yao, Q., Lv, L., Zhang, Y., et al. (2025). Micro-biochar coated on coarse fiber by in situ growth for efficient indoor PM2.5 and ozone removal. Sep. Purif. Technol. 361, 131458. doi:10.1016/j.seppur.2025.131458

CrossRef Full Text | Google Scholar

Xue, M., Liu, J., Zhao, L., and Pei, J. (2022). Identification of odour compounds emitted by wooden boards with the presence of indoor ozone. Build. Environ. 221, 109341. doi:10.1016/j.buildenv.2022.109341

CrossRef Full Text | Google Scholar

Ye, W., Wang, H., Chen, Z., and Zhang, X. (2020). Ozone deposition on free-running indoor materials and the corresponding volatile organic compound emissions: implications for ventilation requirements. Appl. Sci. 10 (12), 4146. doi:10.3390/app10124146

CrossRef Full Text | Google Scholar

Yen, Y. C., Yang, C. Y., Ho, C. K., Yen, P. C., Cheng, Y. T., Mena, K. D., et al. (2020). Indoor ozone and particulate matter modify the association between airborne endotoxin and schoolchildren’s lung function. Sci. Total Environ. 705, 135810. doi:10.1016/j.scitotenv.2019.135810

PubMed Abstract | CrossRef Full Text | Google Scholar

Yue, Z. (2024). Analysis of variation characteristics and source of atmospheric ozone pollution in the yangtze river Delta region. Research of environmental sciences. Res. Environ. Sci. 37 (7), 1500–1512.

Google Scholar

Zhang, Q., Li, L., Zhou, J., Braham, W. W., and Ma, N. (2024). A spatial analysis of ozone and PM2.5 distribution for assessing design factors of healthy buildings. J. Build. Eng. 89, 109357. doi:10.1016/j.jobe.2024.109357

CrossRef Full Text | Google Scholar

Zhang, X., Wang, S. J., Wan, S. C., Li, X., and Chen, G. (2025). Ozone: complicated effects in central nervous system diseases. Med. Gas. Res. 15 (1), 44–57. doi:10.4103/mgr.MEDGASRES-D-24-00005

PubMed Abstract | CrossRef Full Text | Google Scholar

Zhong, L., Lee, C. S., and Haghighat, F. (2017). Indoor ozone and climate change. Sustain. Cities Soc. 28, 466–472. doi:10.1016/j.scs.2016.08.020

CrossRef Full Text | Google Scholar