Comparison of modeled and measured indoor air trichloroethene (TCE) concentrations at a vapor intrusion site: influence of wind, temperature, and building characteristics

There is a lack of vapor intrusion (VI) models that reliably account for weather conditions and building characteristics, especially at sites where active alternative pathways, such as sewer connections and other preferential pathways, are present.

Download Full-text

Evaluation of Passive Diffusive‐Adsorptive Samplers for Use in Assessing Time‐Varying Indoor Air Impacts Resulting from Vapor Intrusion

Groundwater Monitoring & Remediation ◽

10.1111/gwmr.12481 ◽

2021 ◽

Author(s):

Yuanming Guo ◽

Harry O'Neill ◽

Paul Dahlen ◽

Paul C. Johnson

Keyword(s):

Indoor Air ◽

Time Varying ◽

Vapor Intrusion

Download Full-text

Indoor Air Quality (IAQ): Accuracy of Natural Ventilation for Temperature, Air Flow Rate and Relative Humidity (RH) in School Building Classrooms

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.9.15271 ◽

2018 ◽

Vol 7 (3.9) ◽

pp. 42

Author(s):

Norsafiah Norazman ◽

Adi Irfan Che Ani ◽

Nor Haslina Ja’afar ◽

Muhamad Azry Khoiry

Keyword(s):

Air Quality ◽

Relative Humidity ◽

Indoor Air Quality ◽

Indoor Air ◽

Natural Ventilation ◽

Air Flow ◽

Weather Conditions ◽

Potential Health ◽

The Hours ◽

Hot Weather

Indoor Air Quality (IAQ) is an essential matter in achieving students’ satisfaction for the learning process. Building’s orientation is a factor that may encourage sufficient natural ventilation for the classroom occupants. Inadequate ventilation is an issue for most existing classrooms. The purpose of this paper is to analyze the accuracy of natural ventilation in classrooms. Therefore, experimental on 20 classrooms has been conducted by using Multipurpose Meter at secondary school buildings in Malaysia. The findings indicated that the accuracy of natural ventilation testing was below the permissible limits throughout the hours monitored, thus this may cause potential health hazards to the students. Temperature and air flow rates were lower than 23 °C and 0.15 m/s respectively, it fulfilled the basic requirements as a standard learning environment. However, measurements taken showed the overall relative humidity (RH) in the classrooms can be categorized as acceptable with 40% to 70% range. On the basis of these findings, it is evident that naturally ventilated classrooms are important especially due to energy efficiency, whereas mechanical ventilation should only be installed as an alternative under extremely hot weather conditions.

Download Full-text

Long-Term Impacts of Weather Conditions on Indoor Radon Concentration Measurements in Switzerland

Atmosphere ◽

10.3390/atmos13010092 ◽

2022 ◽

Vol 13 (1) ◽

pp. 92

Author(s):

Joan Frédéric Rey ◽

Stéphane Goyette ◽

Mauro Gandolla ◽

Martha Palacios ◽

Fabio Barazza ◽

...

Keyword(s):

Radon Concentration ◽

Indoor Radon ◽

Weather Conditions ◽

Indoor Environments ◽

Indoor Radon Concentration ◽

Prone Area ◽

Building Characteristics ◽

Study Sites ◽

Radon Measurements

Radon is a natural and radioactive gas that can accumulate in indoor environments. Indoor radon concentration (IRC) is influenced, among other factors, by meteorology, which is the subject of this paper. Weather parameters impact indoor radon levels and have already been investigated, but rarely in Switzerland. Moreover, there is a strong need for a better understanding of the radon behaviour inside buildings in Switzerland for public health concerns as Switzerland is a radon prone area. Based on long-term, continuous, and hourly radon measurements, radon distributions classified according to different weather event definitions were investigated and then compared at three different study sites in Western Switzerland. Outdoor temperature influences the most indoor radon, and it is globally anti-correlated. Wind influences indoor radon, but it strongly depends on intensity, direction, and building characteristics. Precipitation influences periodically indoor radon levels relatively to their intensity. Atmospheric pressure and relative humidity do not seem to be huge determinants on IRC. Our results are in line with previous findings and provide a vivid example in Western Switzerland. This paper underlines the different influence complexities of radon, and the need to communicate about it within the broader public and with construction professionals, to raise awareness.

Download Full-text

Indoor air quality in the Swedish housing stock and its dependence on building characteristics

Building and Environment ◽

10.1016/j.buildenv.2013.07.013 ◽

2013 ◽

Vol 69 ◽

pp. 44-54 ◽

Cited By ~ 67

Author(s):

Sarka Langer ◽

Gabriel Bekö

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Housing Stock ◽

Building Characteristics

Download Full-text

Field measurement of PM2.5 concentration in office buildings

E3S Web of Conferences ◽

10.1051/e3sconf/201911106064 ◽

2019 ◽

Vol 111 ◽

pp. 06064

Author(s):

Naoki Kagi ◽

U Yanagi ◽

Kenichi Azuma ◽

Hoon Kim

Keyword(s):

Indoor Air ◽

Air Conditioning ◽

Office Buildings ◽

Central System ◽

Outdoor Concentration ◽

Central Air Conditioning ◽

Building Characteristics ◽

The Individual ◽

Pm2.5 Concentration

The characterization of indoor PM2.5 has been concerned about health effects. PM2.5 in indoor air is affected by not only indoor emissions but also penetrations from outdoor air. Therefore, it is important for indoor PM2.5 to take into account of penetration factors of PM2.5 through air conditioning units in buildings. This study aimed at investigating PM2.5 concentrations and I/O ratios (indoor/outdoor concentration) in office buildings. As a result, the relationships between PM2.5 concentrations or I/O ratios and building characteristics could be classified as the types of buildings, such as specific or non-specific, and air conditioning units, such as the individual or central system. The I/O ratio for the specific buildings, over 3,000 m2 of total floor area and buildings that had the central air conditioning unit was relatively low because of medium performance filter in air conditioning units.

Download Full-text

Radon Investigation in 650 Energy Efficient Dwellings in Western Switzerland: Impact of Energy Renovation and Building Characteristics

Atmosphere ◽

10.3390/atmos10120777 ◽

2019 ◽

Vol 10 (12) ◽

pp. 777 ◽

Cited By ~ 5

Author(s):

Shen Yang ◽

Joëlle Goyette Pernot ◽

Corinne Hager Jörin ◽

Hélène Niculita-Hirzel ◽

Vincent Perret ◽

...

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Energy Efficient ◽

Energy Savings ◽

Geometric Mean ◽

Radon Level ◽

Efficiency Measures ◽

Building Characteristics ◽

Radon Measurements

As part of more stringent energy targets in Switzerland, we witness the appearance of new green-certified dwellings while many existing dwellings have undergone energy efficiency measures. These measures have led to reduced energy consumption, but rarely consider their impact on indoor air quality. Consequently, such energy renovation actions can lead to an accumulation of radon in dwellings located in radon-prone areas at doses that can affect human health. This study compared the radon levels over 650 energy-efficient dwellings in western Switzerland between green-certified (Minergie) and energy-renovated dwellings, and analyzed the building characteristics responsible of this accumulation. We found that the newly green-certified dwellings had significantly lower radon level than energy-renovated, which were green- and non-green-certified houses (geometric mean 52, 87, and 105 Bq/m3, respectively). The new dwellings with integrated mechanical ventilation exhibited lower radon concentrations. Thermal retrofitting of windows, roofs, exterior walls, and floors were associated with a higher radon level. Compared to radon measurements prior to energy renovation, we found a 20% increase in radon levels. The results highlight the need to consider indoor air quality when addressing energy savings to avoid compromising occupants’ health, and are useful for enhancing the ventilation design and energy renovation procedures in dwellings.

Download Full-text

Indoor Air Quality Campaign in an Occupied Low-Energy House with a High Level of Spatial and Temporal Discretization

Applied Sciences ◽

10.3390/app112411789 ◽

2021 ◽

Vol 11 (24) ◽

pp. 11789

Author(s):

Najwa Kanama ◽

Michel Ondarts ◽

Gaëlle Guyot ◽

Jonathan Outin ◽

Evelyne Gonze

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Low Cost ◽

Weather Conditions ◽

Low Energy ◽

Health Impacts ◽

Cumulative Exposure ◽

Temporal Discretization ◽

Low Energy Buildings

Background and gaps. The topic of indoor air quality (IAQ) in low-energy buildings has received increasing interest over the past few years. Often based on two measurement points and on passive measurements over one week, IAQ studies are struggling to allow the calculation of pollutants exposure. Objectives. We would like to improve the evaluation of the health impacts, through measurements able to estimate the exposure of the occupants. Methodology. This article presents detailed IAQ measurements taken in an energy-efficient occupied house in France. Two campaigns were conducted in winter and spring. Total volatile organic compounds (TVOC), formaldehyde, the particle numbers and PM2.5, carbon dioxide (CO2), relative humidity (RH), temperature (T), ventilation airflows, and weather conditions were dynamically measured in several points. Laboratory and low-cost devices were used, and an inter-comparison was carried out for them. A survey was conducted to record all the daily activities of the inhabitants. IAQ performance indicators based on the different pollutants were calculated. Results. PM2.5 cumulative exposure did not exceed the threshold available in the literature. Formaldehyde concentrations were high, in the kitchen, where the average concentrations exceeded the threshold. However, the formaldehyde cumulative exposure of the occupants did not exceed the threshold. TVOC concentrations were found to reach the threshold. With these measurements performed with high spatial and temporal discretization, we showed that such detailed data allow for a better-quality health impacts assessment and for a better understanding of the transport of pollutants between rooms.

Download Full-text