Measurements of Volatile Organic Compounds in a Newly Built Daycare Center

Abstract

We measured temporal changes in concentrations of total volatile organic compounds (TVOCs) and individual volatile organic compounds in a newly built daycare center. The temporal changes of the TVOC concentrations were monitored with a photo ionization detector (PID), and indoor air was sampled and analyzed by Gas Chromatography/Mass Spectrometry (GC/MS) and high performance liquid chromatography (HPLC) to determine the concentrations of the constituent VOCs. The measurements were performed just after completion of the building and again 3 months after completion. The TVOC concentration exceeded 1000 µg·m−3 for all the sampling locations just after completion of building, and decreased almost one tenth after 3 months, to below the guideline values of the TVOC in Japan at 400 µg·m−3. The concentrations of the target VOCs of which the indoor concentrations are regulated in Japan were below the guideline values for all the cases. The air-exchange rates were determined based on the temporal changes of the TVOC concentrations, and it was found that the countermeasure to increase the air exchange rate successfully decrease the TVOC concentration level in the rooms.

A first overview of textile fibers, including microplastics, in indoor and outdoor environments

“…Sampled volumes range between 2 and 5 m 3 depending on occupants presence. The samplings were carried out at a 1.2 m height because it is standardly used to correspond to the breathing height of an adult (Noguchi et al, 2016). Sampling periods ranged between 4 and 7 h. It was carried out discontinuously for both apartments, a part of the sampling in the morning before the inhabitants left home and the other half in the afternoon when they were back home, in order to sample the air only when the they were present.…”

Combined Model for IAQ Assessment: Part 1—Morphology of the Model and Selection of Substantial Air Quality Impact Sub-Models

“…In order to obtain more exact values of the VOC concentrations remaining in the room for the air change rate function, it is possible to use the published dependencies or for the assumed volumes V of ventilated spaces with determinate concentrations, as they can be determined experimentally. A simplified method for determining the ventilation rate N from a simple formula for the time, t, course of a trial ventilation was provided by the Japanese researchers Noguchi et al [41] in 2016. A description of this method is worth reading.…”

“…where I j is the ratio of the gas-phase concentration to the reference concentration value. For example, for the LCI (Lowest Concentration of Interest) value for the jth compound emitted from the building material, the factor R j is dimensionless, since y j is the gas-phase concentration for the jth compound in µg•m −3 , I j is the lowest concentration of interest (LCI) [41] for the jth compound in µg•m −3 and m is the number of all elected compounds. The weight coefficients W j are used as the weights of the equations in the IAQ index, according to:…”

Changes in the concentration of volatile organic compounds and aldehydes in newly constructed houses over time

“…These studies indicate that the concentrations of VOCs in the indoor air of newly built buildings are much higher than the guideline values specified by each country, and Holøs et al (2019) indicated that the off-gassing phase would last at least 2 years. However, Tuomainen et al (2001) showed that VOC concentrations in new houses constructed using low-emitting materials could be reduced by ventilating the houses for 1 week, and Noguchi et al (2016) also concluded that operating the ventilation system for 3 months would effectively reduce VOCs in newly constructed buildings. Herein, in cooperation with a residential building company, we investigated whether the IAQ of seven newly built houses, constructed using low-emission materials, could achieve good air quality; we also noted how much the VOC concentration decreases over time, specifically after 1 week and 1 month of the construction.…”