Building Indoor Air Research Articles

Microplastic levels in the indoor air of buildings based on plastic waste recycling in Indonesia

Introduction: Microplastics are a new type of contamination in the environment caused by plastic fragmentation and degradation. The generation of plastic waste increases every year, therefore efforts are made to recycle it into building materials. It is unclear how building use resulting from recycling plastic waste affects the development of microplastics in the atmosphere. The purpose of this study is to determine the airborne concentrations of microplastics in buildings constructed from recycled plastic waste. Materials and methods: The study measured microplastic levels in the air for 30 days in a miniature building made from plastic waste. Samples taken during the dry season in Indonesia in 2023. Air sampling is carried out by passive method. Visual observation of the shape, and amount of microplastics using a microscope. Results: Microplastics are found in the air of building spaces made from recycled plastic waste with varying levels every day. The average level of microplasty in the air for 30 days was 30,8 particles/m2/day. Maximum microplastic rate of 63 particles/m2/day, and minimum rate of 18 particles/m2/ day. The average air temperature when sampling is 25,48 ºC, air humidity is 68,37 % and ultraviolet intensity is 860 mwatt/cm2. Conclusions: Microplastic levels in the air of building spaces made from recycled plastic waste that can not be identified can be identified whether they are still within safe limits or not. This is because there is no regulation in Indonesia even in the world that regulates the safe limit of microplastic levels in the environment.

Quaternary ammonium salt coated air filter for bioaerosol removal from building indoor air

Developing air filters with biocidal ability is important to protect the public from infectious respiratory diseases. A simple spray-coating approach was devised to fabricate antimicrobial air filters to remove bioaerosols. The commercial antimicrobial agent Goldshield 75 was coated on the air filters through covalent immobilization, endowing the fabricated filter with long-lasting biocidal ability. All coated filters significantly inhibited both Gram-positive bacteria (Micrococcus luteus) and Gram-negative bacteria (Escherichia coli). The antibacterial ability of the coated filters is similar to the commercial AeraSafe antibacterial filter. The coated filter showed over 99.9 % antibacterial efficiency 3 months after the application of the coating. Both bacterial and virus filtration efficiencies of coated charged polypropylene filter were higher than 99.9 %. The coating did not have much effect on the NaCl aerosol filtration efficiency of the filters. This simple spray-coating strategy is a practical method for producing antimicrobial air filters for the prevention of infectious respiratory diseases.

Effect of the urban microenvironment on the indoor air temperature of the residential building stock in the Helsinki region

Due to climate change, there is an increased risk of apartment overheating. In Nordic countries, heatwaves have not been common in the past and hence apartments are not equipped with mechanical cooling systems, so wise urban design might be a solution. This study evaluated the influence of the urban microenvironment on residential building indoor air temperature via green view index (GVI), floor area ratio and distance from the sea. We analyzed a large dataset of over 2000 apartments in the Helsinki region during summers of 2018 and 2021, where severe heatwaves were presented, and combined it with the aforementioned parameters. In the method used, closely situated buildings were clustered into groups by the microenvironment parameters. The results showed consistent correlations between clustered groups and microenvironment parameters, where the best-performing group had an indoor air temperature of about 1 °C lower than the average during the summers and 0.7 °C lower during the severe heatwaves. Building groups with higher GVI demonstrated a greater ability to endure long heatwaves, where combined influence of other urban microenvironment factors was significantly reduced. A substantial influence of sea distance and floor area ratio was observed during short heatwaves in the middle and late summer. The indoor temperature difference of the groups was compared to the average outdoor temperature difference of group areas based on the Finnish Meteorological Institute HARMONIE-AROME weather model implemented with the SURFEX module. The results revealed a consistent correlation between predicted outdoor and indoor temperatures and their distribution of group-to-area differences.

A new clustering method with an ensemble of weighted distance metrics to discover daily patterns of indoor air quality

This paper presents a novel clustering method with an ensemble distance metric to identify meaningful daily patterns of building indoor air quality (IAQ). The novelty of this work is to construct an ensemble of weighted distance metrics with weights being adaptive to the characteristics of IAQ data. The ensemble distance was constructed based on Euclidean distance, Pearson correlation coefficient and cross-correlation coefficient to capture absolute levels, overall trends, and volatilities of IAQ data. The weights for individual distance metrics are automatically adapted to the characteristics of IAQ data based on the Z-scores of the distances among all pair-wise samples in the dataset. In addition, IAQ daily time series are segmented into short sequences to reduce the computational cost. Two datasets containing one-week IAQ observations were used to verify the proposed method. The results showed that the proposed method is able to capture insightful information on the distribution and frequency of the peaks, volatilities, and absolute levels of various IAQ parameters by identifying the patterns with unique characteristics from the IAQ daily sequences. The use of the ensemble distance metric offered better performance with an improved pattern consistency rate of 11–22% when compared with using a single distance metric for IAQ data. The discovered patterns can provide an increased understanding of the pollutant levels, the IAQ changing trends, and the distributions in the peaks and valleys of IAQ pollutants and, hence, can support the optimal operation of building HVAC systems.

Development of indoor work environmental air quality index for a dyeing and printing industry

Introduction: Due to various components, materials, and processes, industrial indoor air quality differs from building indoor air. Air quality and the working environment impact health, performance, and comfort. This study developed an Indoor Work Environmental Air Quality Index (IWEAQI) to assess and characterize industrial work environments.
 Materials and methods: Surat “Textile city” is situated in the western part of India in Gujarat state. The small-scale dyeing and printing industry has been selected as a study area. The industry locations like Jet dyeing machine area, stenter machine area, printing machine area, looping machine area and washing basin area has been selected. Various chemicals, adhesives, solvents, dyes, and varied temperature and humidity conditions are used to transform the raw cloth into the finished product. CO, CO2, SO2, NO2, O3, Total Volatile Organic compounds (TVOC), Formaldehyde, Particulate Matters (PM10, PM2.5), WBGT index, humidity, noise, and light were considered to construct IWEAQI. Continuous observations were recorded at minute intervals with a real-time monitoring system. To account for all contributing aspects, United States Environmental Protection Agency (USEPA) air quality index technique was updated for index formulation. IWEAQI was validated using the Pollution Index approach.
 Results: The proposed approach calculated IWEAQI from results. Both approaches gave an index value of 46-80. The developed approach and pollution index method were compared using regression analysis. All study locations had regression values between 0.93 and 0.99.
 Conclusion: The technique classifies IWEAQI as excellent (0-20), good (21-40), moderate (41-60), poor (61-80), and very poor (81-100). From the developed index value, which parameters are influencing the most can be judged.
 

Effects of Indoor Environmental Quality in Urban Housing on Residents' Health and Wellbeing in Nigeria

The building industry's contribution as a non-clinical contributor to the quality of life is its impact on occupants' health. A health-based standardised questionnaire and a digital data collection device were used to investigate the susceptibility of building indoor air quality (IAQ) to infectious diseases. PM2.5 (63 μm/m3) and PM10 (228 μm/m3) obtained exceeded the international standard. Some associations between certain building characteristics and potential risk factors for certain diseases were seen. This study provides a platform for future intervention in housing and public health policies and addresses the conundrum of safe and healthy buildings for the urban populace in Nigeria

Evaluating the effects of indoor air quality on teacher performance using artificial neural network

PurposeA building's Indoor Air Quality (IAQ) has a direct impact on the health and productivity on its occupants. Understanding the effects of IAQ in educational buildings is essential in both the design and construction phases for decision-makers. The purpose of this paper is to outline the impact air quality has on occupants' performance, especially teachers and students in educational settings.Design/methodology/approachThis study aims to evaluate the effects of IAQ on teachers' performances and to deliver air quality requirements to building information modelling-led school projects. The methodology of the research approach used a quasi-experiment through questionnaire surveys and physical measurements of indoor air parameters to associate correlation and deduction. A technical college building in Saudi Arabia was used for the case study. The study developed an artificial neural network (ANN) model to define and predict relationships between teachers' performance and IAQ.FindingsThis paper contains a detailed investigation into the impact of IAQ via direct parameters (relative humidity, ventilation rates and carbon dioxide) on teacher performance. Research findings indicated an optimal relative humidity with 65%, ranging between 650 to 750 ppm of CO2, and 0.4 m/s ventilation rate. This ratio is considered optimum for both comfort and performanceOriginality/valueThis paper focuses on teacher performance in Saudi Arabia and used ANN to define and predict the relationship between performance and IAQ. There are few studies that focus on teacher performance in Saudi Arabia and very few that use ANN in data analysis.

Spatial and seasonal variations in the carbon and lead isotopes of PM2.5 in air of residential buildings and their applications for source identification

To understand isotope distributions of PM2.5 in residential buildings and apply them for source identification, carbon (δ13C) and lead (Pb) isotope ratios in indoor and outdoor air of residential buildings were analyzed. Moreover, factor analysis (FA) was employed to investigate sources, which were compared through isotopic analyses. The average δ13C values of indoor air are −26.94 ± 1.22‰ and −27.04 ± 0.44‰ in warm (August to October) and cold (February to March) seasons, respectively, and the corresponding values for outdoor air are −26.77 ± 0.54‰ and −26.57 ± 0.39‰. The average 206Pb/207Pb (208Pb/207Pb) ratios of indoor air are 1.1584 ± 0.0091 (2.4309 ± 0.0125) and 1.1529 ± 0.0032 (2.4227 ± 0.0081) in warm and cold seasons, respectively, and the corresponding values for outdoor air are 1.1594 ± 0.0069 (2.4374 ± 0.0103) and 1.1538 ± 0.0077 (2.4222 ± 0.0085). Seasonal variation in δ13C values or Pb isotope ratios of indoor air was not significant, and similar results were obtained for outdoor air. Significant differences were not observed between δ13C values or Pb isotope ratios of indoor and outdoor air. Traffic emission is the major contributor to indoor and outdoor PM2.5 based on isotopic analyses; this result was consistent with the results of FA. The δ13C values of indoor air in buildings with poor ventilation conditions were significantly lighter than those of outdoor air. In summary, the spatial and seasonal variations of isotopes were similar in residential buildings, which can be used to identify sources of indoor PM2.5, and ventilation condition is an influencing factor.

Simulation of a desiccant air-conditioning system integrated with dew-point indirect evaporative cooler for a school building

In this study, a desiccant based air-conditioning system supported by a dew-point indirect evaporative cooler, a direct evaporative cooler, two heat recovery units was investigated during a complete cooling season for air-conditioning of a school building located in Adana, Turkey. A mathematical model of the air-conditioning system was developed by deriving new equations for modelling two key components of the system, namely desiccant wheel and dew-point indirect evaporative cooler using the available correlations and experimental data. Effectiveness of desiccant wheel and dew-point evaporative cooler, heat transfer rates realized in the main system components, the thermal energy requirement to drive the system and cooling performance of the system are investigated thoroughly. The effect of desired building indoor air temperature and mixing ratio of exhaust air on the operation and performance of the system was detailed. The results show that it is possible to obtain desired comfort conditions within the building during complete cooling season with the air-conditioning system considered. The monthly average thermal COP is maximum in October with 0.78 and minimum in July with 0.22. The seasonal thermal COP of the system is 0.43.

A study of the impact of attacked façades on microbial contamination of the indoor air

The concentration of moulds in interiors varies over a wide range and is significantly related to the mould concentration in the outdoor air. According to other studies, the mould propagules concentration in the outdoor environment depends on the season of the year, examination location, and climatic conditions. The façade attacked by biological agents is considered to be more of a technical or aesthetic problem. This study compares the results of mapping microbial infestation of façade with levels of microbial ambient air contamination and also with microbial air contamination levels inside housing units of ten buildings in the Czech Republic. The obtained data show that the attacked facade of the building can affect the indoor air of buildings by increasing the number of moulds propagules spreading in the air and their genus representation.

Internet of Things (IoT) Technologies for Managing Indoor Radon Risk Exposure: Applications, Opportunities, and Future Challenges

Radon gas is a harmful pollutant with a well-documented adverse influence on public health. In poorly ventilated environments, that are often prone to significant radon levels, studies indicate a known relationship between human radon exposure and lung cancer. Recent technology advances, notably on the Internet of Things (IoT) ecosystem, allow the integration of sensors, computing, and communication capabilities into low-cost and small-scale devices that can be used for implementing specific cyber-physical systems (CPS) for online and real-time radon management. These technologies are crucial for improving the overall building indoor air quality (IAQ), contributing toward the so-called cognitive buildings, where human-based control is tending to decline, and building management systems (BMS) are focused on balancing critical factors, such as energy efficiency, human radon exposure management, and user experience, to achieve a more transparent and harmonious integration between technology and the built environment. This work surveys recent IoT technologies for indoor radon exposure management (monitoring, assessment and mitigation), and discusses its main challenges and opportunities, by focusing on methods, techniques, and technologies to answer the following questions: (i) What technologies have been recently in use for radon exposure management; (ii) how they operate; (iii) what type of radon detection mechanisms do they use; and (iv) what type of system architectures, components, and communication technologies have been used to assist the referred technologies. This contribution is relevant to pave the way for designing more intelligent and sustainable systems that rely on IoT and Information and Communications Technology (ICT), to achieve an optimal balance between these two critical factors: human radon exposure management and building energy efficiency.

THE EFFECT OF ROOF INTEGRATED PHOTOVOLTAIC (RIPV) ON BUILDING INDOOR AIR IN AFRICAN TROPICAL CLIMATE

Photovoltaic energy has the potential to become one of the major energy sources used in the households in the tropical region of Africa, where the solar radiation intensity is abundant and almost constant over the year. Solar photovoltaic systems present many advantages when they are integrated in the building structure envelope and have a significant influence on the indoor air temperature of dwelling buildings due to the thermal resistance modification. In this paper, a simplified model of the photovoltaic system integrated on the roof of a residential building according to the building construction customs and materials has been designed and modelled. The heat transfer is studied in several situations: with and without a Building Integrated Photovoltaic (BIPV) system, for a building with and without false ceiling. The BIPV system, installed over an effective area of 35 m2 increases the building indoor air temperature of approximately 5°C which is corrected by the heat insulation optimization of the false ceiling made up with building local materials. The final indoor air temperature obtained are in good agreement with the ASHRAE standards and can therefore be applied in tropical regions.

Key performance indicators for the evaluation of building indoor air temperature control in a context of demand side management: An extensive analysis for Romania

Besides being the main consumer of energy, buildings can be smart energy hubs offering demand side flexibility for the grid. The main loads in buildings are heating and cooling and they have the advantage to be flexible if controlled in a smart way. There are plenty of ways in which controllers can act for increasing the demand side energy flexibility of buildings and different approaches in quantifying and assessing it.This study uses a set of three existing key performance indicators to make a qualitative assessment on how the heating and cooling energy control is impacting indoor thermal comfort, the costs with energy and the self-consumption of the locally produced energy for a typical household located in different geographical conditions in Romania, under an electricity market design with a demand response program. The selected metrics are adapted for this analysis to allow a quick qualitative evaluation on how the building and its systems can reach the maximum achievable potential in terms of comfort, costs, and self-consumption. This approach can be applied both at design and operational phase. The results show that the participation in a demand response program does not influence negatively the indoor thermal comfort if constraints are imposed on these parameters, that the geography does not have a relevant impact upon the costs if a control technique dedicated for the participation in the demand response program is implemented and the participation in a demand response program does not influence the self-consumption.

Research progress and consideration of VOC pollution control in healthy buildings in China

In China, VOC pollution in indoor air is quite serious, and the control of VOC concentration in indoor air has always been a difficult problem. It is also an important control target of healthy buildings in China, since VOC has significant health hazards to human body. This paper introduces the definition and source of volatile organic compounds in indoor air, analyses the present situation of pollution and expounds the human hazards of VOC. There are differences between VOC control indexes in China and other countries in terms of indoor air quality standards. In the future revision of standards, health needs, industry status and implement ability should be fully considered. There are three ways to control indoor VOC pollution: Source control, ventilation dilution and air purification. Source control is the most fundamental way to avoid indoor air pollution. The identification of “health performance” of building materials and furniture products will be the main development direction. The main idea of control is “release rate” instead of “content” control method. For high-risk substances, developing alternative products is the most direct solution, but this method depends on technological progress. Diluting indoor air pollutants with outdoor fresh air is the most convenient way to reduce VOC concentration. How to achieve precise ventilation according to the emission characteristics of pollution sources will be the main task of ventilation research in healthy buildings. Air purification is an indispensable means of controlling indoor air pollution in modern buildings. With the standard limit of VOC concentration in indoor environment getting lower and lower, the application of air purification technology will be more and more widely. High CADR, high CCM, low resistance and no secondary pollution will become the main development direction. Since 2017, JGJ/T 436-2018 ( Technical Standard for Interior Decoration Pollution Control of Residential Buildings ) and JGJ/T 461-2019 ( Design Standard for Controlling Indoor Air Quality of Public Building ) have been released successively. They fill in the standard gap in the architectural design stage, and require architectural designers to systematically consider the guarantee of indoor air quality. These two standards play an important role in promoting the promotion of healthy building. GB 50325 ( code for Indoor Environmental Pollution Control of Civil Building Engineering ) and GB/T 18883 ( Indoor Air Quality Standard ) are still the two most commonly used evaluation standards in building indoor air quality control in China. When these two standards are implemented, they all tend to adopt the instantaneous evaluation method, that is, to use the concentration data of a certain day for conformity evaluation. Therefore, how to evaluate the long-term total exposure risk of VOC is also one of the important problems in the future. VOC control in building indoor air in China can be roughly divided into three stages: The first stage focuses on product control, the second stage focuses on engineering control, and the third stage focuses on human exposure. In the future, with the implementation of health buildings evaluation standards in China, the number of indoor air quality indicators will be more and more, the limits will be more and more stringent, and the corresponding solutions will be constantly changing. How to systematically control VOC will become a major challenge in healthy buildings.

Comprehensive review of 2-ethyl-1-hexanol as an indoor air pollutant.

Objectives2‐Ethyl‐1‐hexanol (2EH), a fragrance ingredient and a raw material for the production of plasticizer di(2‐ethylhexyl) phthalate, is responsible for sick building syndrome (SBS). This review aims to clarify the 2EH characteristics as an indoor air pollutant such as indoor air concentration, emission mechanism, toxicity, and clinical effects.MethodsScientific publications in English that has been made available on PubMed as of June 2018 and ad hoc publications in regional languages were reviewed.ResultsInhalation exposure to 2EH caused mucous membrane irritation in the eyes, nose, and throat in experimental animals. Studies in human volunteers revealed an increase in olfactory irritation and eye discomfort. There has been increasing evidence of 2EH being present in indoor air in buildings. The primary sources of 2EH emissions are not building materials themselves, but instead the hydrolysis of plasticizers and flooring adhesives. In particular, compounds like di(2‐ethylhexyl) phthalate present in polyvinyl chloride flooring materials are hydrolyzed upon contact with alkaline moisture‐containing concrete floors. That being said, it may be observed that indoor concentrations of 2EH increased every year during summer.ConclusionsUnlike other volatile organic compounds that cause SBS, 2EH can be retained in indoor air for long durations, increasing the likelihood of causing undesirable health effects in building occupants exposed to it. As a precautionary measure, it is important to use flooring materials that do not emit 2EH by hydrolysis, or to dry concrete before covering with flooring materials.

Modelling of vapour intrusion into a building impacted by a fuel spill in Antarctica

A new vapour intrusion contaminant transport model was designed specifically to allow an assessment of the impact of a hydrocarbon fuel spill on air quality in cold region buildings. The model is applied to a recent situation in Antarctica, where a diesel spill impacted the construction of a new building. For the first time, this model allows consideration of the diffusive resistance of different vapour barrier to the transport of hydrocarbons into the building and an assessment of the effectiveness of different products. Site specific indoor air criteria are derived. Five scenarios are modelled at field temperatures: (1) build on current contaminated site; (2) excavate contaminated soil, backfill with clean soil and assess impact of residual contamination; (3) excavate and backfill with remediated (biopile) soil; (4) backfill with remediated soil and assess impact of residual contamination; (5) backfill with remediated soil and assess impact of a potential future fuel spill. Two different vapour barriers, a co-extruded ethylene vinyl alcohol (EVOH) geomembrane (VB1) and a linear low-density (LLDPE) geomembrane (VB2), are investigated for each scenario and compared to a base case with no vapour barrier, providing quantifiable evidence of the benefit of installing an engineered vapour barrier Contaminant concentrations were below regulatory limits for Scenarios (2–5) with VB1 and air exchange in the building. For all scenarios, the EVOH geomembrane (VB1) was consistently superior at reducing vapour transport into the building indoor air space over the LLDPE geomembrane (VB2) and no vapour barrier. The risk mitigation measures developed for this contaminated Antarctic site may be relevant for other buildings in cold regions.

Energy saving potential of an air treatment system for improved building indoor air quality in Singapore

The design of air conditioning mechanical ventilation (ACMV) system affects the building energy performance and the indoor pollutant removal process. The present study aims to reduce energy consumption on ACMV systems by employing a renewable air treatment system (ATS). The ATS is able to purify the recirculated air through the ozone-based oxidation process and air scrubbing devices. The air purification performance of primary equipment in the ATS has been studied in order to demonstrate the capability to remove indoor air pollutants. Due to the air purification process, the ATS allows a reduced supply of outdoor-air translating to a lower cooling load. In addition, the reduced outdoor-air fraction results in an improved chiller efficiency. Therefore, the ATS is capable of achieving marked energy savings because of the reduced cooling load for conditioning outdoor airflow. The proposed ATS is particular adept during a period when Singapore faces periodic bad haze situations. Activating the ATS while decreasing the outdoor-air fraction can be an attractive solution. Based on Singapore climatic condition, an energy consumption analysis has been carried out to estimate the energy saving potential of the proposed ATS with varying outdoor-air intake. The “plug-and-play” ATS can be easily integrated into any new or existing ACMV systems to realize immediate improvement in indoor air quality and building energy efficiency.

Adaptive approach of thermal comfort and correlation between experimental data and mathematical model in some schools and traditional buildings of Madagascar under natural ventilation

A good ventilation is important to improve indoor air in buildings. In Sub-Saharan Africa regions and other countries, both health and productivity are indeed elements depending on indoor comfort. The purpose of this research is to suggest a new thermal comfort approach based on subjective responses of occupants and mathematical models. There is a lack of data about indoor comfort in residential buildings in the tropical islands of Indian Ocean and the aim of the research is to propose guidelines for more comfortable constructions in Madagascar and other countries of the Indian Ocean. Experimental and subjective data were collected in 67 traditional habitats and 25 public and private schools, located in 25 districts of urban communes in the Northern Madagascar. Mathematical modelling was based on Rohles approach. At total of 992 questionnaires were collected and analysed during rainy and dry seasons. The results showed that traditional buildings were more comfortable than schools. Comfort temperature varied from 24.6 to 28.4 °C during both seasons in residences and schools. When the indoor air temperature varied in the 24.5–27.5 °C range, more than 80% of peoples were satisfied.

Estimation of the residential radon levels and the annual effective dose in dwellings of Shiraz, Iran, in 2015.

IntroductionRadon is the second most important cause of lung cancer after smoking. Thus, the determination of indoor radon concentrations in dwellings and workplaces is an important public health concern. The purpose of this research was to measure the concentration of radon gas in residential homes and public places in the city of Shiraz and its relationship with the type and age of the buildings as well as the type of materials used to construct the building (brick, block). We also determined the radon dosages that occupants of the building would receive.MethodsThe present study is a descriptive-analytical and cross-sectional research that was conducted on the building’s indoor air in the city of Shiraz in 2015. Using geographic information system (GIS) software and a spatial sampling cell with an area of 25 square kilometers, 200 points were selected. In this study, we used passive diffusive samplers as Solid State Nuclear Track Detector (SSNTD) CR-39 polycarbonate films for three months in the winter. Sampling was conducted in accordance with the U.S. Environmental Protection Agency’s protocol. We determined the concentrations of radon gas at the time of sampling, and calibration factors were determined. The data were analyzed by IBM-SPSS, version 20, descriptive statistics, Kruskal-Wallis, and Mann–Whitney tests.ResultsThis study showed that the average radon concentration was 57.6 ± 33.06 Bq/m3 in residential dwellings. The average effective dose was 1.45 mSv/y. The concentration of radon in 5.4% of the houses was found to be greater than 100 Bq/m3, which is above the level allowed by the World Health Organization (WHO).ConclusionSince radon is the second leading cause of lung cancer, it seems necessary to increase the public’s awareness of this issue and to take action to reduce radon in homes when the concentrations are above the WHO’s guideline.

The impact of design ventilation rates on the indoor air quality in residential buildings: An Italian case study

The paper investigates the effects on building indoor air quality (IAQ) resulting from the choice of different design ventilation rates. A reference residential building was analysed by means of the multizone modelling software CONTAM, by monitoring the concentration of two pollutants: occupant-generated carbon dioxide (CO2) and total volatile organic compounds (TVOC) from indoor sources. A demand-controlled ventilation strategy based on building occupancy was implemented and users' presence schedules were defined. Specifically, the evolution of indoor pollutant concentrations was investigated when the design ventilation rates, recommended by two IAQ-related standards (the Italian UNI 10339 and the European EN 15251), were implemented through a mechanical ventilation system. Different results regarding the IAQ level were achieved accordingly to the dissimilar ventilation rates. After a statistical analysis on the distributions of CO2 and TVOC concentrations, EN 15251 outcomes showed overall better results of the analysed statistical metrics, i.e. prevalence, sensitivity and accuracy. Indeed, the EN 15251 design airflows led to indoor conditions that were more often classified either in the correct air quality class or in a higher class. Finally, a better alignment between the national and European IAQ standards is recommended, especially in terms of airflows, air quality classes and pollutant limit values.