The Prevention of the Snow Entrance to the HVAC-systems

SUMMARY Entrance of snow into the HVAC-systems is common problem in the arctic-and sub-arctic climates and may cause moistening or wetting of filters and outdoor air chambers which promotes microbe growth. Blocking the filters also increases pressure drop or even damages the filters. The design features and velocity of air in the outdoor air intake play key role when the problems occurs. To eliminate the snow entrance into the HVAC-systems the face velocity of the outdoor air shall be below 1 m/s at the intake louvre. The pressure caused by wind is one of the external conditions that influence the snow penetration through the intake louvre and some solutions for elimination of this problem are presented. If the snow, however, is entranced to the HVAC-system good design and hygiene control of the intake section of the HVAC-system is important which is discussed more detailed in this paper

Exposure of cleaning workers to chemical agents and physical conditions in swimming pools and spas

Swimming pools and spas require a high hygiene level, and therefore constant cleaning. In this study, cleaning workers’ exposure to volatile organic compounds (VOCs), trichloramine (TCA), and particulate matter (PM) in the swimming pools and spas were evaluated. Also, statistical methods were employed to determine what activities affect the exposure to disinfection byproducts (DBPs). The study was conducted in 32 swimming pools and spas. The measurement locations were pool areas, bathrooms, and locker rooms, both during cleaning and opening hours. During the cleaning, the total volatile organic compound (TVOC) concentrations were low, on average 96, 251, and 91 µg/m3 for locker rooms, bathrooms, and pool areas, respectively. Similarly, during the opening hours, the TVOC concentrations were on average 78, 125, and 83 µg/m3, for locker rooms, bathrooms, and pool areas, respectively. This is in line with previous studies investigating cleaning work in other environments. The most prevalent compounds during the cleaning were 2-(2-butoxyethoxy)ethanol (DEGBE), 2-(2-ethoxyethoxy)ethanol (DEGEE), 2-butyl-1-octanol, trichloromethane (chloroform), decamethylcyclopentasiloxane (D5), and carbon tetrachloride. The most prevalent compounds during the opening hours were D5, D-limonene, carbon tetrachloride (bathrooms and pool areas), and trichloromethane (bathrooms and pool areas). The TCA concentrations during the cleaning in the bathrooms and pool areas were on average 60 and 67 µg/m3, respectively, and during the opening hours, 28 and 122 µg/m3, respectively. The use of disinfectants was found to increase the TCA concentration in the bathrooms, while the other cleaning products did not. Even though the TCA concentrations were below the WHO’s guideline and the Finnish occupational exposure limit value of 500 µg/m3, the measured TCA levels were occasionally high enough to pose a risk of irritative symptoms. The PM concentrations were low, both in the real-time monitoring (aerodynamic diameter, Dae ≤ 15 µm) and inhalable dust samples (Dae ≤ 100 µm). Highest measured inhalable dust concentration was 350 µg/m3, well below the Finnish occupational limit value of 5,000 µg/m3 for organic inhalable dust.</p

VOCs concentrations and emission rates in hospital environment and the impact of sampling locations

In this study, volatile organic compounds (VOCs) were measured from 47 hospital rooms to determine the most suitable sampling location for VOCs indoors. Another goal was to find out the most predominant VOCs and their emission per floor area in a hospital environment. Three samples were taken from each room simultaneously: one from the center of the room, one from the floor near the wall, and one from the exhaust air terminal. Concentrations of the VOCs were relatively low in all the cases, and the most abundant compounds were decamethylcyclopentasiloxane, d-limonene, xylenes, and 2-methyl-2-propanol. The average emission rates of the main compounds per floor area varied between 49 and 81 mu g/m(2)h. Statistical analyses showed that room area and volume affected differently the total volatile organic compounds (TVOC) concentrations among the sampling locations. Concentrations were higher at the exhaust air terminal than in samples at the floor and middle of the room. VOC levels were the same at the different sampling locations when the size of the room was below 10 m(2). However, field measurements and statistical analyses showed that when the size of the room increased, the most evenly distributed VOCs can be measured most reliably in the vicinity of the exhaust terminal device or in the exhaust air

Weathering of Antibacterial Melt-Spun Polyfilaments Modified by Pine Rosin

For many antibacterial polymer fibres, especially for those with natural functional additives, the antibacterial response might not last over time. Moreover, the mechanical performance of polymeric fibres degrades significantly during the intended operation, such as usage in textile and industrial filter applications. The degradation process and overall ageing can lead to emitted volatile organic compounds (VOCs). This work focused on the usage of pine rosin as natural antibacterial chemical and analysed the weathering of melt-spun polyethylene (PE) and poly lactic acid (PLA) polyfilaments. A selected copolymer surfactant, as an additional chemical, was studied to better integrate rosin with the molecular structure of the plastics. The results reveal that a high 20 w-% of rosin content can be obtained by surfactant addition in non-oriented PE and PLA melt-spun polyfilaments. According to the VOC analysis, interestingly, the total emissions from the melt-spun PE and PLA fibres were lower for rosin-modified (10 w-%) fibres and when analysed below 60 ℃. The PE fibres of the polyfilaments were found to be clearly more durable in terms of the entire weathering study, i.e., five weeks of ultraviolet radiation, thermal ageing and standard washing. The antibacterial response against Gram-positive Staphylococcus aureus by the rosin-containing fibres was determined to be at the same level (decrease of 3–5 logs cfu/mL) as when using 1.0 w-% of commercial silver-containing antimicrobial. For the PE polyfilaments with rosin (10 w-%), full killing response (decrease of 3–5 logs cfu/mL) remained after four weeks of accelerated ageing at 60 ℃

Massiivipuun päästöt sisäilmaan : Kirjallisuuskatsaus

Rakennus- ja sisustusmateriaaleista ja -tuotteista haihtuvien päästöjen määrät ovat nousseet materiaalien, liimojen, pinnoitteiden, tapettien jne. keskeisiksi laatuvaatimuksiksi. Vähäpäästöisyys on erityisen tärkeää rakennettaessa tai remontoitaessa kohteita riskialttiille ryhmille, kuten allergikoille. Puusta sisäilmaan haihtuvia yhdisteitä on tutkittu viime vuosikymmeninä, mutta tutkimusten lähtökohdat ja tulosten esitystavat vaihtelevat siinä määrin, että asioiden omaksuminen ilman merkittävää ajankäyttöä on aiheeseen syvällisesti perehtymättömälle vaikeaa. Puun sisäilmapäästöistä on kirjoitettu joitain englanninkielisiä yhteenvetoja ja kirjallisuuskatsauksia, mutta aihepiirin kattavaa suomenkielistä tarkastelua ei ole ollut käytettävissä. Tämä raportti kokoaa kansainvälistä ja kotimaista tutkimustietoa puhtaan puun sisäilmapäästöistä. Kaikista puulajeista haihtuu yhdisteitä ympäröivään ilmaan, mutta päästöjen määrä ja koostumus vaihtelevat muun muassa puulajin, näytetyypin ja näytteen käsittelytavan mukaan. Puun interaktio ympäröivän ilman kanssa voidaan estää tai sitä voidaan vähentää pintakäsittelyllä, mutta päästöjen hallinnan näkökulmasta se on tarpeen vain poikkeustapauksissa. Puusta haihtuvien terveydelle haitallisten yhdisteiden pitoisuudet ovat normaaleissa käyttöolosuhteissa niin vähäisiä, ettei suomalaisen puun sisäkäytön rajoittamiselle ole perusteita. Poikkeuksen tekevät tilat, joissa sisäilman laadulle asetetaan erityisvaatimuksia (esim. yliherkkyyskohteet) – tällöinkin päästöjä on helppo hallita esimerkiksi puulajivalinnalla. Vasta-asennetusta puutuotteesta haihtuvien yhdisteiden kokonaispitoisuuden perusteella ei tule tehdä päätelmiä sisäilman laadusta, koska suurin osa yhdisteistä on harmittomia ja päästöt laskevat nopeasti asennuksen jälkeen. Terveydelle ja hyvinvoinnille haitallisten yhdisteiden päästöille on määritelty sekä EU-tasolla että kansallisesti raja-arvoja, joita sisäilman laatuun vaikuttavissa kohteissa käytettävät tuotteet eivät saa ylittää. Puu luetaan kotimaisessa päästöluokituksessa vähäpäästöiseen M1-luokkaan yhdessä lasin, keraamien, luonnonkiven, metallien ja tiilen kanssa. Puu on kuitenkin hygroskooppinen materiaali, josta haihtuvien yhdisteiden määrä ja koostumus muuttuvat ympäristöolosuhteiden (lämpötila, ilmankosteus) mukaan. Niinpä vakioiduissa olosuhteissa tehdyistä päästömittauksista ei voi tehdä suoraviivaisia päätelmiä koskien puun sisäilmapäästöjä esimerkiksi eri vuodenaikoina

Level of Satisfaction of Admitted Patients

&nbsp;Background: To determine the level of satisfaction of admitted patients in respect of three components of health services (doctors, nurses, facilities) in different wards and its comparison of level of satisfaction between male and female patients.Methods: In this cross sectional study admitted patients (n= 170) were surveyed using close-ended questionnaire. The variables noted were age, gender, type of room or ward, satisfaction with doctors, nurses and health facilities measured using different variables for each. Satisfaction level was graded as satisfied, no comments, not satisfied and was compared between male and female patients.Results: Out of 170 patients 82.53% were satisfied with health facilities. Most satisfying variables were attitude of doctors for which 91% were satisfied with it and timeliness of nurses as 90% patients were satisfied with it. Most unsatisfying variable was free medication availability as 61% were dissatisfied; followed by cleanliness with which 23% were dissatisfied; and thirdly, expertise of nurses, with it 17% were dissatisfied. Overall 15.84% patients were dissatisfied with health services.Conclusion: There was a reasonable degree of satisfaction in admitted patients of Holy Family Hospital with health services provided to them except for free medication and hygien

Asbestipurkutyön turvallisuuden ja siihen liittyvien testaus- ja mittaustoimintojen kehittäminen : AsbTest

Tutkimuksessa kehitettiin ja ohjeistettiin sellaisia asbestipurkutyön turvallisuuden mittaus- ja valvontakäytäntöjä, joiden avulla työntekijöiden ja muiden ihmisten asbestialtistuminen voidaan ennaltaehkäistä. Hankkeessa kehitetyillä ja testatuilla mittausmenetelmillä voidaan todentaa osastoinnin, ilmankäsittelylaitteiden ja hengityksensuojainten toimivuus. Turvallisessa asbestipurkutyössä yksikään riskinhallintamenetelmä ei saa pettää ja niiden tehokkuutta tulee seurata mittauksin. Tutkimuksen tulosten pohjalta laadittiin malliratkaisut altistumisen ehkäisemiseksi. Tuloksia voidaan soveltaa myös kaikessa muussa korjausrakentamisessa, jossa ilmaan vapautuu terveydelle haitallisia tai vaarallisia altisteita