Indoor Ammonia Research Articles

Simulating indoor inorganic aerosols of outdoor origin with the inorganic aerosol thermodynamic equilibrium model ISORROPIA.

Outdoor aerosols can transform and have their composition altered upon transport indoors. Herein, IMAGES, a platform that simulates indoor organic aerosol with the 2-dimensional volatility basis set (2D-VBS), was extended to incorporate the inorganic aerosol thermodynamic equilibrium model, ISORROPIA. The model performance was evaluated by comparing aerosol component predictions to indoor measurements from an aerosol mass spectrometer taken during the summer and winter seasons. Since ammonia was not measured in the validation dataset, outdoor ammonia was estimated from aerosol measurements using a novel pH-based algorithm, while nitric acid was held constant. Modeled indoor ammonia sources included temperature-based occupant and surface emissions. Sensitivity to the nitric acid indoor surface deposition rate was explored by varying it in model runs, which did not affect modeled sulfate due to its non-volatile nature, though the fitting of a filter efficiency was required for good correlations of modeled sulfate with measurements in both seasons. Modeled summertime nitrate well-matched measured observations when , but wintertime comparisons were poor, possibly due to missing thermodynamic processes within the heating, ventilating, and air-conditioning (HVAC) system. Ammonium was consistently overpredicted, potentially due to neglecting thirdhand smoke impacts observed in the field campaign, as well as HVAC impacts.

EFFECTS OF FERMENTED MEALWORM LARVAE MEAL WITH DIFFERENT PROBIOTICS ON LITTER QUALITY IN BROILER HOUSE

This study was conducted to investigate the effects of the supplementation of fermented mealworm larvae meal with two different probiotic bacteria (Lactobacillus plantarum or Lactobacillus brevis) to diets of broilers reared normal or high stocking density on litter quality. Wood shavings, commonly used in broiler houses, are used as litter material. High stocking density significantly increased litter moisture content compared to that of broiler reared normal stocking density (P<0.0001). Dietary supplementing of fermented mealworm larvae meal with Lactobacillus plantarum or Lactobacillus brevis significantly decreased litter moisture content compared to that of control diet (P<0.0001). High stocking density significantly increased litter pH level compared to normal stocking density (P<0.0001). On the other hand, dietary treatments had no significant effect on litter pH. High stocking density significantly increased ammonia gas emissions in the 5th day (P<0.05) and 7th day (P<0.0001) compared to normal stocking density. Furthermore, feeding on diets supplemented with fermented mealworm larvae meal with Lactobacillus plantarum or Lactobacillus brevis numerically decreased ammonia gas emissions in the 5th and 7th days although their effects on ammonia gas emissions are not significant. It was concluded based on present findings that fermented mealworm larvae meal with probiotics can be used as a natural feed additive to prevent the problems resulted from wet litter and high indoor ammonia levels in broiler houses.

Indoor exposure levels of ammonia in residences, schools, and offices in China from 1980 to 2019: A systematic review.

Indoor ammonia (NH3 ) pollution has been paid more and more attention in view of its health risk. However, few studies have investigated the exposure level in the non-occupational environment in China. This study systematically reviewed the indoor ammonia exposure level in different regions, the equivalent exposure concentration of different populations, and the factors that influence indoor air ammonia in residences, offices, and schools in China. The literature published in 1980-2019 from main databases was searched and detailed screened, and finally, 56 related studies were selected. The results illustrated that the median concentration of indoor air ammonia in residences, offices, and school buildings was 0.21mg/m3 , 0.26mg/m3 , and 0.15mg/m3 . There were 46.4%, 71.4%, and 40% of these samples exceeding the NH3 standard, respectively. The national concentrations and the equivalent exposure levels of adults and children were calculated and found to be higher than 0.20mg/m3 . The concentration of ammonia varied greatly in different climate zones and economic development regions. Higher concentrations were found in the severe cold zone and the regions with higher economic level. This review reveals a high exposure risk of indoor air ammonia and the crucial impact of human emission, indoor air temperature, new concrete, and economic level, suggesting further investigation on indoor air ammonia evaluation and health effects.

On-site performance investigation of liquid-desiccant air-conditioning system applied in laboratory rodent room: A comparative study

Considerable ventilation rates in laboratory animal rooms indicate huge energy consumption of air-conditioning systems. The liquid-desiccant air-conditioning (LDAC) system is regarded as an energy-efficient system, which can help to save energy in laboratory animal rooms. However, limited studies have applied LDAC systems to this kind of rooms for energy conservation. In this study, a demonstration project is focused on, wherein both the LDAC system and conventional vapor-compression system are used in the laboratory rodent center. On-site measurements were conducted to reveal the energy performance difference between the two systems. The test results reveal that the considerable cooling loads of two rodent rooms air-conditioned by the conventional system and LDAC system are 482.1 W/m2 and 576.8 W/m2, respectively, under the summer conditions in Beijing. The LDAC system can avoid reheating and recover cooling from the exhaust air from indoors. Thus, the coefficient of performance (COPsys) of the LDAC system ranges 3.5–4.5, whereas the COPsys of the conventional system only ranges 1.8–2.3 during the test period. During the entire cooling season, an electric power saving rate of 37.3% can be achieved by the LDAC system. Moreover, although both systems can satisfy all the environment control requirements, the LDAC system is beneficial for particulate matter filtration, yet slightly unfavorable for reducing indoor ammonia concentration, compared to the conventional system.

Study of Risk Assessment of Indoor NH3 in Two Urban Households of NCR-Delhi

Indoor air pollution is a matter of serious concern in the mega cities which are grappling with poor air quality. There are very few reports available that discuss the indoor air quality of gaseous ammonia (NH3). This study reports the abundance and risk assessment of NH3 in two distinct urban households of Delhi city during July 2017 to June 2018. Results showed that the NH3 concentrations were consistently higher during entire sampling period at the Dwarka household (DH) site which represented the residential sector having an average value of 102.5 µg/m3, as compared to the Mayapuri household (MH) site which represented the industrial sector having an average value of 57.2 µg/m3. The spatio-temporal analysis suggested a characteristic seasonal influence as indoor concentrations were very high during monsoon season following the order, monsoon > summer > post-monsoon ≥ winter, at DH site but indoor NH3 at MH site did not show any remarkable seasonal variation except a sweeping increase during monsoons. Short term and long term health risk characterisation using multiple appropriate toxicological end limits for NH3 in the two households showed that at its present concentrations indoor NH3 cannot be a health hazard to the inmates. However, it does not fail to escape our notice that mushrooming urban areas with their complex problems such as poor sanitation, industrialisation, waste management, high vehicular traffic, high occupant density, etc. have become major hubs of continual rise in indoor ammonia.

Efficiency of Various Reagents on Ammonia Reduction in Litter Removal From Belt Conveyors for Battery Cages

With the development of technogenic civilization, various anthropogenic factors (ionizing radiation, toxic substances, etc.) affect virtually all living organisms, and often this effect is negative. The current state of affairs on many poultry farms is that they have a negative impact on the surrounding biosphere due to harmful emissions. This is due to the accumulation of litter. The purpose of the study was to investigate the microclimate parameters in the poultry house with the addition of various reagents and zeolite in the belt conveyors of cage batteries. It was proposed to add adsorbents (zeolite) and chemical reagents (phosphogypsum, superphosphate, and aluminium chloride and iron sulphate) directly onto the litter removal belt conveyors of cage batteries. It was found that application of zeolite onto the conveyor belt in an amount of 600 g/m2 reduces the content of ammonia in the premises by 1.6 times on the first day of accumulation of litter, and by 1.25 times on the seventh day, not exceeding during all seven days of maximum allowable concentrations. However, within all seven days of litter accumulation, a difference in this indicator with control was statistically significant (P=0.001). The reduction of ammonia emissions was less significant when applying a dose of zeolite of 300 g/m2 conveyor belt: by 1.6 times on the first day of accumulation of litter, and from the fifth day the difference with control was statistically significant. The application of phosphogypsum onto the conveyor belt in the amount of 600 g/m2 provided a reduction of ammonia emission by 2.1-1.1 times, 300 g/m2-by 1.8 times on the first day of accumulation of litter. Since the fifth the day, the difference in control was statistically significant. The application of superphosphate onto the litter removal conveyor belts reduced the ammonia content in the poultry house in almost the same extent as when applying phosphogypsum. The effective time of this reagent was also close in importance. Aluminium chloride and ferrous sulphate were used in smaller doses than other absorbents and reagents, but on the initial five days of litter accumulation, they provided a relatively significant reduction in the ammonia content of the air in the poultry house: ferrous sulphate at a dose of 200 g/m2 of the conveyor belt area - by 2.0-1.2 times, aluminium chloride - by 4.0-1.5 times. Anyway, the efficacy of these reagents in the last days of litter accumulation was considerably decreased. The use of aluminium chloride and ferrous sulphate in doze of 100 g/m2 for the conveyor belt provided a proper reduction of indoor ammonia content only for the initial tree-four days.

Observations and Contributions of Real-Time Indoor Ammonia Concentrations during HOMEChem.

Although ammonia (NH3) is usually found at outdoor concentrations of 1-5 ppb, indoor ammonia concentrations can be much higher. Indoor ammonia is strongly emitted from cleaning products, tobacco smoke, building materials, and humans. Because of ammonia's high reactivity, solubility in water, and tendency to sorb to a variety of surfaces, it is difficult to measure, and thus a comprehensive evaluation of indoor ammonia concentrations remains an understudied topic. During HOMEChem, which was a comprehensive indoor chemistry study occurring in a test house during June 2018, the real-time concentration of ammonia indoors was measured using cavity ring-down spectroscopy. A mean unoccupied background concentration of 32 ppb was observed, with further enhancements of ammonia occurring during cooking, cleaning, and occupancy activities, reaching maximum concentrations during these activities of 130, 1592, and 99 ppb, respectively. Furthermore, ammonia concentrations were strongly influenced by indoor temperatures and heating, ventilation, and air conditioning (HVAC) operation. In the absence of activity-based sources, the HVAC operation was the main modulator of ammonia concentration indoors.

Simultaneous determination of indoor ammonia pollution and its biological metabolite in the human body with a recyclable nanocrystalline lanthanide-functionalized MOF.

A Eu(3+) post-functionalized metal-organic framework of nanosized Ga(OH)bpydc(Eu(3+)@Ga(OH)bpydc, 1a) with intense luminescence is synthesized and characterized. Luminescence measurements reveal that 1a can detect ammonia gas selectively and sensitively among various indoor air pollutants. 1a can simultaneously determine a biological ammonia metabolite (urinary urea) in the human body, which is a rare example of a luminescent sensor that can monitor pollutants in the environment and also detect their biological markers. Furthermore, 1a exhibits appealing features including high selectivity and sensitivity, fast response, simple and quick regeneration, and excellent recyclability.

Environmental assessment of three egg production systems–Part I: Monitoring system and indoor air quality

To comprehensively assess conventional vs. some alternative laying-hen housing systems under U.S. production conditions, a multi-institute and multi-disciplinary project, known as the Coalition for Sustainable Egg Supply (CSES) study, was carried out at a commercial egg production farm in the Midwestern United States over two single-cycle production flocks. The housing systems studied include a conventional cage house (200,000 hen capacity), an aviary house (50,000 hen capacity), and an enriched colony house (50,000 hen capacity). As an integral part of the CSES project, continual environmental monitoring over a 27-month period described in this paper quantifies indoor gaseous and particulate matter concentrations, thermal environment, and building ventilation rate of each house. Results showed that similar indoor thermal environments in all three houses were maintained through ventilation management and environmental control. Gaseous and particulate matter concentrations of the enriched colony house were comparable with those of the conventional cage house. In comparison, the aviary house had poorer indoor air quality, especially in wintertime, resulting from the presence of floor litter (higher ammonia levels) and hens’ activities (higher particulate matter levels) in it. Specifically, daily mean indoor ammonia concentrations had the 95% confidence interval values of 3.8 to 4.2 (overall mean of 4.0) ppm for the conventional cage house; 6.2 to 7.2 (overall mean of 6.7) ppm for the aviary house; and 2.7 to 3.0 (overall mean of 2.8) ppm for the enriched colony house. The 95% confidence interval (overall mean) values of daily mean indoor carbon dioxide concentrations were 1997 to 2170 (2083) ppm for the conventional cage house, 2367 to 2582 (2475) ppm for the aviary house, and 2124 to 2309 (2216) ppm for the enriched colony house. Daily mean indoor methane concentrations were similar for all three houses, with 95% confidence interval values of 11.1 to 11.9 (overall mean of 11.5) ppm. The 95% confidence interval values (overall mean) of daily mean PM10 and PM2.5 concentrations, in mg/m3, were, respectively, 0.57 to 0.61 (0.59) and 0.033 to 0.037 (0.035) for the conventional cage house, 3.61 to 4.29 (3.95) and 0.374 to 0.446 (0.410) for the aviary house, and 0.42 to 0.46 (0.44) and 0.054 to 0.059 (0.056) for the enriched colony house. Investigation of mitigation practices to improve indoor air quality of the litter-floor aviary housing system is warranted.

Ammonia concentrations in a free-stall dairy barn

AbstractThe paper presents the results of research on indoor ammonia (NH3) concentrations in the air in a free-stall barn. The differences in measurement results mainly depended on the season and weather conditions. The study also showed a significant correlation (P<0.01) between the NH3 concentration and temperature, relative humidity and air movement velocity inside the barn. The lowest NH3 concentration was recorded in the summer (0.0 ppm) in the presence of high air temperatures, low humidity and increased exchange of ventilated air. In winter during severe frosts, highest ammonia concentration (8.0 ppm) was noted, caused by limited ventilation. The highest daily ammonia concentration was usually recorded during the night. This was due to increased relative air humidity and low air velocities. It was concluded that the average level of ammonia of 2.73 ppm during the entire year was significantly below values defined as harmful for animals and people.

Degradation of Typical Indoor Air Pollutants Using Fe-Doped TiO2Thin Film under Daylight Illumination

A type of iron-doped titania thin film was prepared by means of sol-gel method to degrade indoor formaldehyde (HCHO), ammonia (NH3), and benzene (C6H6) under sunlight. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis spectroscopy, and energy dispersive spetra (EDS). The results showed that the iron was doped in the TiO2photocatalyst successfully. The absorption edge of doped TiO2had red shifts and the doped TiO2had a stronger absorption than the pure TiO2in the visible region. Fe-doped TiO2thin film prepared with the optimal preparation condition could remove indoor HCHO, NH3and C6H6effectively under solar light irradiation. The removal percentage of HCHO, NH3or C6H6after 9 h photocatalytic reaction under solar light reached 55%, 53.1%, and 37.5%, respectively, when they existed in the air individually. When the three pollutants were mixed in the air, the removal percentage decreased to 33.3%, 28.3%, and 28%. The degradation reaction of the three pollutants followed the pseudo first-order kinetics, which reflects that the photocatalytic reaction was controlled by the surface chemical reaction and the reaction rate was controlled by concentration of reactants.

Flow-based ammonia gas analyzer with an open channel scrubber for indoor environments

A robust and fully automated indoor ammonia gas monitoring system with an open channel scrubber (OCS) was developed. The sample gas channel dimensions, hydrophilic surface treatment to produce a thin absorbing solution layer, and solution flow rate of the OCS were optimized to connect the OCS as in-line gas collector and avoid sample humidity effects. The OCS effluent containing absorbed ammonia in sample gas was injected into a derivatization solution flow. Derivatization was achieved with o-phthalaldehyde and sulfite in pH 11 buffer solution. The product, 1-sulfonateisoindole, is detected with a home-made fluorescence detector. The limit of detection of the analyzer based on three times the standard deviation of baseline noise was 0.9ppbv. Sample gas could be analyzed 40 times per hour. Furthermore, relative humidity of up to 90% did not interfere considerably with the analyzer. Interference from amines was not observed. The developed gas analysis system was calibrated using a solution-based method. The system was used to analyze ammonia in an indoor environment along with an off-site method, traditional impinger gas collection followed by ion chromatographic analysis, for comparison. The results obtained using both methods agreed well. Therefore, the developed system can perform on-site monitoring of ammonia in indoor environments with improved time resolution compared with that of other methods.

Degradation of Indoor Ammonia Using TiO<sub>2</sub> Thin Film Doped with Iron(III) under Visible Light Illumination

A type of titania thin film doped with iron(III) was prepared by means of sol-gel method to degrade indoor ammonia (NH3) under visible light irradiation. The photocatalysts was characterized by X-ray diffraction (XRD) and UV-vis spectroscopy. The results demonstrated that the adsorption edge of doped TiO2 thin film had red shifts and the doped TiO2 thin film had a stronger absorption than undoped TiO2 thin film in the visible region. Doping amount of Fe(III) effected the photocatalytic actitivity of Fe-doped TiO2 thin film significantly. The optimal doping amount of Fe(III) was 1%(mole fraction). Using the optimal Fe-doped TiO2 thin film, the removal percentage of NH3 after 9h phtocatalytic reaction under visible light reached 53.1%. The degradation reaction of NH3 was successfully described by the pseudo first-order kinetics. The reaction rate constant decreased with the increase of initial concentration of NH3, which reflected that there was oxidation competition between NH3 and its intermediate during the photocatalytic process.

A Comparison of Measurement Methods of Indoor Ammonia in New Buildings

A Comparison of Measurement Methods of Indoor Ammonia in New Buildings

A case of indoor air pollution of ammonia emitted from concrete in a newly built office in Beijing

A case of suspected indoor ammonia contamination from concrete was investigated in an airline company office in Beijing. A standardized questionnaire on indoor environment perceptions, medical symptoms and psychosocial work environment was distributed to all staff, and compared with a reference group of office workers from the same company in Stockholm. Temperature, relative humidity, formaldehyde, volatile organic compounds (VOC), ammonia, and carbon dioxide were measured both in Beijing and Stockholm. In Beijing mould and bacteria were also measured. Totally 95% ( N = 14) participated. The Beijing staff reported a higher rate of complaints regarding poor work satisfaction, and work stress as compared to the Stockholm reference group. In the total material ( N = 203) the psychosocial environment was related to general symptoms (headache and tiredness) but not odour perception or mucous membrane symptoms. Controlling for age, smoking habits, and psychosocial work environment the Beijing staff had more complaints on unpleasant odour and mucous membrane symptoms. An increased indoor concentration of ammonia (3–6 ppm) and benzene (26.8 μg/m 3) was measured in the indoor air in the Beijing office, as compared to the office in Stockholm (<0.1 ppm ammonia and 0.4 μg/m 3 benzene). The ammonia contamination in the Beijing office was confirmed, the probable source being additives in the concrete. The ammonia level was well below the Swedish threshold limit values (TLV) (25 ppm). In addition the exposure to benzene, an indicator of traffic exhaust pollution was high both indoors and outdoors in Beijing, possible related to increased levels of odour complaints and mucous membrane irritation.

Ammonia Emissions from Two Empty Broiler Houses with Built-Up Litter

Ammonia (NH3) emissions from broiler houses have been monitored almost exclusively while the house is populated with live birds. Many American growers utilize litter for more than one flock. Between flocks, various litter management practices are used to prepare this built-up litter for the next flock, including some degree of house ventilation to keep the indoor ammonia concentration low. Ammonia volatilized from the litter is emitted to the environment during the downtime. This ammonia emission should be accounted for in the determination of a facility's annual ammonia emission inventory. In the study reported here, ammonia emissions were monitored from two recently depopulated broiler houses in Pennsylvania using built-up litter managed for five consecutive flocks. Average house air temperature during the monitoring period was 10.2C, well below the typical temperature during flock production. Emission was calculated whenever a house exhaust fan was running. The results revealed ammonia emissions from the houses ranging from 212 to 1107 g h-1. The daily emission rate (ER) was highest on day 2, coinciding with the first harrowing of the litter, and then decreased over subsequent days. These average values during downtime were about one-quarter of the ER values for market-size birds observed during flock grow-out in the same houses over the previous year. The reduced ER during the cleanout period was anticipated, since the built-up litter was at a lower temperature than during grow-out and there was no further fresh manure addition contributing to potential ammonia volatilization. Observed variation between these two houses with identical management and construction showed that monitoring a single house may not accurately predict empty house emissions, with unidentified factors other than management being responsible for this variability.

Preparation of fibrous TiO 2 photocatalyst and its optimization towards the decomposition of indoor ammonia under illumination

Aqueous dispersion containing TiO 2 particles was firstly prepared and then mixed with silicone or acrylic additives to establish a treating bath. And the fibrous TiO 2 photocatalysts were produced by padding three woven fabrics including cotton, polyester and flax fabrics as support materials with this treating bath and some factors affecting the preparation process were discussed. Moreover, the fibrous TiO 2 photocatalysts were characterized by X-ray diffractometer, infrared Fourier transform spectrometer and scanning electron microscope, and evaluated with respect to the removal efficiency of ammonia under UV irradiation in air stream by a specifically designed photocatalytic reactor and environmental condition simulated chamber. The results showed that ammonia gas could well be decomposed by the fibrous TiO 2 photocatalysts based on cotton and flax fabrics. Increasing the dosage of TiO 2 aqueous dispersion led to the improved ammonia decomposition level of the fibrous TiO 2 photocatalysts. The additives caused the reduced ammonia decomposition level of the fibrous TiO 2 photocatalysts, but provided it with the enhanced resistance to water washing. The ammonia photocatalysis of the fibrous TiO 2 photocatalysts was not much affected by curing temperature and dyed cotton fabrics when preparing.

Decomposition of indoor ammonia with TiO 2-loaded cotton woven fabrics prepared by different textile finishing methods

Addition of urea-based antifreeze admixtures during cement mixing in construction of buildings has led to increasing indoor air pollution due to continuous transformation and emission of urea to gaseous ammonia in indoor concrete wall. In order to control ammonia pollution from indoor concrete wall, the aqueous dispersion was firstly prepared with nano-scale TiO 2 photocatalysts and dispersing agent, and then mixed with some textile additives to establish a treating bath or coating paste. Cotton woven fabrics were used as the support materials owing to their large surface area and large number of hydrophilic groups on their cellulose molecules and finished using padding and coating methods, respectively. Two TiO 2-loaded fabrics were obtained and characterized by X-ray diffractometer (XRD) and scanning electron microscopy (SEM). Moreover, a specifically designed ammonia photocatalytic system consisting of a small environmental chamber and a reactor was used for assessing the performance of these TiO 2-loaded fabrics as the wall cloth or curtains used in house rooms in the future and some factors affecting ammonia decomposition are discussed. Furthermore, a design equation of surface catalytic kinetics was developed for describing the decomposition of ammonia in air stream. The results indicated that increasing dosage of the TiO 2 aqueous dispersion in treating bath or coating paste improved the ammonia decomposition. And ammonia was effectively removed at low ammonia concentration or gas flow rate. When relative humidity level was 45%, ammonia decomposition was remarkably enhanced. It is the fact that ammonia could be significantly decomposed in the presence of the TiO 2-padded cotton fabric. Whereas, the TiO 2-coated cotton fabric had the reduced photocatalytic decomposition of ammonia and high adsorption to ammonia owing to their acrylic binder layer. Finally, the reaction rate constant k and the adsorption equilibrium constant K values were determined through a curve-fitting method and the TiO 2-padded cotton fabric had the higher k value and lower K value than the TiO 2-coated cotton fabric.

Heterogeneous Decomposition of Indoor Ammonia in a Photoreactor with TiO2-Finished Cotton Fabrics

Addition of urea-based antifreeze admixtures during cement mixing can make it possible to concrete cement in construction of buildings in cold weather. This, however has led to increasing indoor air pollution due to continuous transformation and emission from urea to gaseous ammonia in indoor concrete walls. In order to control ammonia from indoor concrete walls, aqueous dispersion of nano-titanium dioxide (TiO2) was prepared and mixed with silicone additive to establish a treating bath. Cotton fabrics were finished with this treating bath by using pad-dry-cure process and then characterized by X-Ray Diffractometer, Infrared Fourier Transform Spectrometer and Scanning Electron Microscope. The gaseous ammonia was derived from an environmental condition simulated chamber. The heterogeneous decomposition of gaseous ammonia by UV/TiO2 process in an annular photoreactor fixed with the TiO2-coated cotton fabric was studied under various dosages of aqueous nano-TiO2 dispersion, initial ammonia concentration, relative humidity and gas flow rate. A design equation of surface catalytic kinetics was developed for describing the decomposition of ammonia in air streams by UV/TiO2 process at given operating conditions. Experimental results indicated that increasing dosage of aqueous nano-TiO2 dispersion improved the ammonia decomposition of cotton fabric, which was prepared. At a constant temperature of 25°C, ammonia in the air stream was effective removed by decreasing initial ammonia concentration and gas flow rate. For moisture in the range of 15-65%, when the relatively humidity level was increased to 45%, the decomposition of ammonia was remarkably enhanced, and the decomposition of ammonia could be inhibited by excessive moisture.

오존 처리가 자돈사내 공기의 질과 자돈의 성장 효율에 미치는 영향

The present study was performed to investigate the effect of ozonation of the swine nursery building on indoor air quality and growth efficiency of the weanling piglets. Forty 21-day-old, cross-bred weanling piglets were housed in two ozonated or unozonated pens(10 males and 10 females per pen) for 3 wk alternately in a swine nursery building and this procedure was repeated three times. Ozone was generated using a commercial apparatus outside the nursery building and infused into the nursery building through a duct at a level of 0.03 ppm. Indoor concentrations of harmful gases were measured at 2-h intervals for a 24-h period per each 3-wk feeding trial. Indoor ammonia and carbon dioxide gas concentrations were reduced by the ozonation(P 0.01) by 21% and 7%, respectively, compared with those of the control(unozonation), although hydrogen sulfide concentration was not affected by the treatment. However, the weight gain, feed intake and feed/gain of the piglets did not change due to the ozonation. Results suggest that ozonation of the swine nursery building is effective for improving the indoor air quality without affecting the production efficiency of weanling piglets.