© Inštitut za sanitarno inženirstvo, 2013.  Original scientific article Analysis of sanitary- -technical and hygienic conditions of slovenian kindergartens and proposed measures Katarina KACJAN ŽGAJNAR1, An GALIČIČ, Urška ZoRAN, Luka PAJEK, Mateja DoVJAK2* ABsTRACT Most children in early childhood spend approximately one third of the day in kindergartens. Therefore, it is essential that their stay in an educational institution is comfortable and without adverse health effects. Statistical data over the last decade show that the amount of enrol ed children in kindergartens has increased. The problem of overcrowded kindergartens is usual y solved by changing the existing norms for class sizes, or with alternative spaces that do not serve the original purpose. According to EU Directives, kindergartens are among building facilities that have to be renovated. The purpose of the paper was to analyse sanitary-technical and hygienic conditions of the selected playrooms of kindergartens and to define measures. Real-state conditions were evaluated in 35 playrooms of 16 kindergartens in the Central Slovenian region. The main emphasis was on the used materials, their cleaning capability, room acoustics, natural daylight, safety and comfort issues, as well on their possible adverse health effects. The combination of observation, measurements and Received: 11. 11. 2013 calculations of reverberation time, and comparison with regulation demands Accepted: 17. 12. 2013 was carried out. In many playrooms sanitary-technical and hygienic conditions did not fulfil regulation demands. Irregularities are mainly related to improper instal ation of final coverings, to low parapet heights and total opening area of windows, poor hygienic conditions, and selection of materials that may present health risks. Calculated and measured reverberation times deviated from 1 Senior Lecturer, MSc. Katarina Kacjan optimal values. Žgajnar, dipl. san. inž. University of Ljubljana Faculty of Health Sciences Key words: playrooms, sanitary-technical conditions, hygiene, noise, measures Zdravstvena pot 5, 1000 Ljubljana katarina.kacjan@zf.uni-lj.si * Corresponding author Assistant, PhD. Mateja Dovjak, dipl. san. inž. University of Ljubljana Faculty of Civil and Geodetic Engineering Chair for Buildings and Constructional Complexes, Jamova cesta 2 1000 Ljubljana, Slovenia mdovjak@fgg.uni-lj.si 4 International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. INTRoDUCTIoN In Slovenia, children are included in the system of pre-primary education (i.e. kindergartens, day-care centres, preschool) from the end of the ma- ternity leave (i.e. 11 month old) til starting compulsory education [1]. According to preschool legislation, learning standards and guidelines [2- 5], the maximum kindergarten class sizes are from 14 to 24 children, depending on the child age, special needs and disabilities. Kindergartens present biological, physical and social environment where a child usual y spends approximately one-third of the day. The environment of kindergar- Kindergartens present ten has a strong interactive influence on a child [6], so it is very impor- biological, physical and social tant to assure a high level of safety without any health risks. environment where a child Children represent a specific population group, mainly due to their lower usual y spends approximately body weight, higher activity levels and age-related behavioural charac- one-third of the day. The teristics. In the childhood, the immune system is not ful y developed, so environment of kindergarten children are more susceptible to environmental influences [7,8] than has a strong interactive adults. Moreover, entering kindergarten also presents a physiological influence on a child, so it is health risk for a child (i.e. stress). Epidemiological data indicate an in- creased morbidity among children in the first months of visiting kinder- very important to assure a gartens [9]. high level of safety without any health risks. Statistical data of the Republic of Slovenia showed that in the school year 2012/13 almost 77 % of all children of proper age were enrol ed in kindergartens. The number of enrol ed children in kindergartens in- creased from 70 % in school year 2008/2009 to 77 % in school year 2012/13 [10]. The EU benchmark on pre-school participation stipu- Epidemiological data indicate lates that by 2020 at least 95 % of children between the age of 4 and an increased morbidity among the starting age of compulsory education should participate in early children in the first months of childhood education [10-12]. Despite large amount of children enrol ed in early childhood education system, many existing buildings do not ful- visiting kindergartens. fil pre-school standards and guidelines. Moreover, the problem of over- crowded kindergartens is usual y solved by changing existing norms for class sizes, or with alternative spaces that usual y do not serve the orig- inal purpose (i.e. containers, mobile houses). For example, the average For example, the average age age of the selected kindergarten buildings in the Central Slovenian re- of the selected kindergarten gion is 1978. According to EU Directives [13-15], kindergartens are among the building facilities, which have to be renovated. buildings in the Central Slovenian region is 1978. Current studies on kindergartens and health issues are mainly focused According to EU Directives, on chemical risks, i.e. chemical pol utants in indoor air [16,17], metal contamination [18,19], radon emission sources [20]; biological risks, kindergartens are among the i.e. transmission of biological agents [21-23], microbiological quality building facilities, which have and safety of food [24] as well on physical risks, i.e. noise [25-28]. The to be renovated. review by Le Cann et al. [29] was taking a broad approach to the in- door environment and including chemical, microbial, physical and social aspects. Noise as a physical health risk in kindergartens presents well re- searched topic [25-27]. McAl ister et al. [25] studied children’s expo- sure to background noise at the ears during a normal day in three day- care centres in Linköping, Sweden. Chatzakis et al. [26] performed measurements of noise levels in occupied and unoccupied classrooms International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 5 K. Kacjan Žgajnar, A. Galičič, U. Zoran e  t al. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measures in overall ten kindergartens in the city of Heraklion, Crete, Greece. Sjö- din et al. [27] carried out an investigation on 101 employees at 17 pre- schools in Umea° county, Sweden. Voss [28] investigated the correla- tion between the reverberation time (that is the time that would be required for the sound pressure level in the enclosure to decrease by 60 decibels after the source has been stopped) and the resulting room noise level, as well as the correlation between the one-hour room noise levels and the number of children present in day-care centres, Den- mark. Kovačič and Kacjan Žgajnar [30] and Kacjan Žgajnar et al. [31,32] measured equivalent and impulse levels of noise in kindergar- tens in Ljubljana, Slovenia. The results from the above studies often ex- ceeded the permissible noise levels for working and living environments [33-35]. Based on the results by Voss [28], three main factors for ef- fective reduction of noise levels in day-care centres were defined, i.e. physical surroundings (buildings, rooms, etc.), the number of children, and social behaviour. Other guidances in schools also include acoustic [36] as well as educational measures [37]. The effectiveness of meas- ures for the reduction of noise levels was evaluated in a few studies. Gerhardsson and Nilsson [38] studied noise-related problems in per- sonnel at Swedish day-care centres before and after acoustical treat- ment. L’Espérance et al. [39] performed measures of noise levels, re- Studies dealing with overall verberation time and the surface radiation factor at 40 locations in 20 sanitary-technical and day-care centres in Quebec. Instal ing an acoustic ceiling and adding a hygienic issues of band of acoustic panels at the top of the wal s reduced noise levels on kindergarten playrooms are average by 6 to 7 dBA [39] and 2 to 6 dB [38]. There even exist de- rare. However, there are no fined recommendations for the reduction of noise levels in kindergar- defined measures important tens, but there is still a large gap between recommended implementa- for building design and tion and execution. Studies dealing with overall sanitary-technical and hygienic issues of kindergarten playrooms are rare. However, there are renovation. no defined measures important for building design and renovation. The purpose of our paper is to analyse sanitary-technical and hygienic conditions of selective playrooms of kindergartens in the Central Slove- nian region. The main emphasis was on the used materials, their clean- ing capability, room acoustics, natural daylight, safety and comfort is- sues, as well on their possible adverse health effects. The main findings will be compared with current regulations and guidelines. Based on the comparison, measures important for building design stage, construction and renovation will be prepared. sTATIsTICAL BACKGRoUND: sLoVENIA, EU In Slovenia, in the school year 2012/13, almost 77 % of all children of the proper age are enrol ed in kindergartens [10]. In the school year 2012/13, 938 kindergartens and their units were providing pre-school education; this is 16 more than in the previous school year [10]. The majority (95 %) of kindergartens are public; only 50 or 5 % are private. In the school year 2012/13 the number of children enrol ed in kinder- gartens increased by 2.3 % over the previous school year, but the growth is not as high as in the school years 2008/09 to 2011/12, 6 © Inštitut za sanitarno inženirstvo, 2013. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. when the annual growth rate was around 7 %. Slightly more than 83,000 children were enrol ed in kindergartens and in child-minders’ families, which is 76.7 % of all children of the proper age. Compared to the previous school year, the number of children particularly increased in the second age period (children from the age of 3 up to entering ba- sic school), which represented a 3.3 % increase in enrolment, so that the share now stands at almost 90 %. In the first age period (children up to 3 years) the number of children increased only slightly. Kindergar- tens now include more than half of the children in this age group. Slightly more than 38,500 4- and 5-year-olds are enrol ed in pre-school education, which is 93.3 % of all children of that age [10]. In the school year 2012/13 pre-school care and education in kindergartens is provid- ed by about 10,453 professional staff, of whom 4,986 are educators and 5,467 assistant educators. There are 2 % men – mostly assistant educators – among professional staff. There are on average 8.1 children per educator and assistant educator; in the first age period 6.2 children and in the second age period 9.4 children [10]. According to EU statistics [11,12], there was a significant rise in chil- dren attending pre-primary education, from 85.6 % in 2000 to 92.5 % in 2009 (between the age of 4 and the start of compulsory primary education). In Belgium, Spain, France, Italy and the Nether- According to EU statistics, lands, al children are enrolled at the age of 4 until the start of (com- there was a significant rise in pulsory) primary education, while Germany, Cyprus, Latvia, Lithuania, children attending pre-primary Austria, Poland, Portugal, Romania, Slovenia, Finland and Sweden education, from 85.6 % in have seen significant increases in participation over the period. In general, in the EU Member states, high levels of children attending 2000 to 92.5 % in 2009 pre-primary education correspond with high employment rates of (between the age of 4 and the women [11,12]. start of compulsory primary education). METHoDs Analysis of sanitary-technical and hygienic conditions was performed from March to May 2013 in 35 playrooms (for children age from 3 to 6 years) of 16 kindergartens in the Central Slovenian region. General characteristics of playrooms and population group are described in Ta- ble 1. According to the required demands [3] the main observed groups of sanitary-technical and hygienic parameters were: material type (floor, wal , ceiling covering), cleaning capability (instal ation of cove fil et, washable wall covering), safety (parapet height, protection of radiator surfaces), natural daylight (window-to-floor ratio), comfort (instal ation of wall covering up to 1.2 m high, thermal properties-warm/cool feeling to touch), basic hygienic conditions (dust, curtains), room acoustics (re- verberation time). Real-state conditions were evaluated according to EU and SI legislation. Possible adverse health effects were defined accord- ing to reviewed studies. Room acoustics were evaluated with calculated and measured rever- beration times. Reverberation time was calculated with Sabine formula Eq. (1) [40-42], Eyring formula Eq. (2) [41-43] and Mil ington-Sette for- mula Eq. (3) [44-46]. International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 7 K. Kacjan Žgajnar, A. Galičič, U. Zoran e  t al. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measures (1) where T is calculated reverberation time with Sabine formula [s], V is the S volume of the room [m3], A is the sum of the surface areas of the room multiplied by their respective absorption coefficients at a given frequency and m is the absorption coefficient as a function of air absorption and frequency [m-1]. Sabine formula (Eq. 1) should be used for rooms with volumes less than 200 m3 and a reasonable distribution of sound and lower sound absorption (absorption coefficient less than 0.2) [41,42]. (2) where T is calculated reverberation time with Eyring formula [s], where Ey V is the volume of the room [m3], S is the total surface area of the room in [m2], α– is average absorption coefficient [-] and m is the absorption coefficient as a function of air absorption and frequency [m-1]. Eyring formula (Eq. 2) should be used for rooms with higher sound absorption (absorption coefficient more than 0.2) [41,42]. (3) where T is calculated reverberation time with Mil ington-Sette formula M-S [s], V is the volume of the room [m3], α is the sound absorption coefficient 1 as sub-area S. Mil ington-Sette formula [44-46] should be used when the i materials of a room have a wide variety of absorption coefficients [46]. Absorption coefficients at 500 Hz (relevant for child voice, baby cry, unoc- cupied room [47]) were selected from the relevant literature [48]. For the calculation it was assumed that the rooms were unoccupied. Measurements of reverberation time were performed in two typical playrooms (playroom No. 28, located in kindergarten M; playroom No. 33 located in kindergarten O). Measurements were conducted accord- ing to the standards [49,50]. Reverberation time was measured with calibrated modular precision sound analyser type 2260 Investigator, manufacturer Brüel and Kjaer. The observed sanitary-technical and hygienic conditions were evaluated according to the Rules on the criteria and the minimum technical re- quirements for space and equipment of kindergartens [3], Rules on the acoustic insulation in buildings [41], TSG-1-005:2012 [42], Rules on the protection of workers from the risks related to exposure to noise at work [33], Rules on the ventilation and air-conditioning of buildings [51], Regulation (EU) No 305/2011 [15] of the European Parliament and of the Council of 9 March 2011 laying down harmonised conditions for the marketing of construction products and repealing Council Direc- tive 89/106/EEC. Calculated and measured reverberation times were compared to opti- mal levels for classrooms according to [42]. 8 © Inštitut za sanitarno inženirstvo, 2013. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. T = 0,32 log V – 0,17 (4) opt where T is calculated optimal reverberation time [s] and V is the vol- opt ume of the room [m3]. REsULTs AND DIsCUssIoN Design of active spaces According to regulation demands [3], all active spaces in kindergarten have to be functional y designed according to child age. The position of active spaces must be transparent and directly connected to the central area. The plan of the playroom should be dynamic with minimum sur- face area 40 m2. The examined 35 playrooms were functional y designed according to child age group 3-6 years with transparent and direct connection to the central area. All plans were dynamic, but the surface areas of 13 play- rooms (No. 1, No. 3, No. 7-9, No. 16, No. 22, No. 25, No. 26, No. 28 and No. 30-32) were less than 40 m2; surface areas of the fol owing 4 playrooms were less than 35 m2 (No. 1, No. 3, No. 7, No. 9). Playroom Construction No. of No. of professional Table 1: Kindergarten No. year [yr] children [ ] staff [ ] Analysed 35 playrooms of A 1 21 2 16 kindergartens (A-P) in the 1952 2 23 3 Central Slovenian region and B 3 1982 24 2 population group. C 4 19 2 5 1973 24 2 6 23 2 D 7 21 2 8 20 2 9 1976 20 2 10 21 3 11 23 2 E 12 1976 21 3 F 13 19 2 1979 14 20 3 G 15 2005 22 2 16 2013 24 2 HI 17 1971 19 2 18 24 2 J 19 19 2 20 23 2 21 1972 21 2 22 18 2 23 19 2 K 24 2 1963 21 25 19 3 26 21 2 L 27 1906 20 3 M 28 1979 22 4 N 29 20 2 30 1976 21 2 31 22 2 32 21 2 O 33 1976 19 2 P 34 2012 24 2 35 23 2 International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 9 K. Kacjan Žgajnar, A. Galičič, U. Zoran e  t al. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measures sanitary-technical conditions Results of the evaluation of sanitary-technical conditions of the 35 play- rooms in 16 kindergartens in the Central Slovenian region are pre- sented in Table 2. Fulfilment of regulated demands is marked with + (evaluated real-state condition fulfil ed regulation demand) or – (evalu- ated real-state condition did not fulfil regulation demand). Used materials in playrooms and their health issues Regulation (EU) No. 305/2011 [15] of the European Parliament and of the Council of 9 March 2011 laying down harmonised conditions for the marketing of construction products and repealing Council Directive 89/106/EEC define basic requirements for construction works and con- struction products (materials) that have to be fulfil ed throughout the whole life cycle of a building. The construction works as a whole and their separate parts must be fit for their intended use, taking into ac- count in particular the health and safety of persons involved throughout the life cycle of the works. Some of the main issues of the Regulation are hygiene, health and environment; safety and accessibility in use; The majority of materials used protection against noise explicitly defined in basic requirements No. 3, in playrooms were wood No. 4 and No. 5. The Regulation [15] shall be binding in its entirety (particle boards, plywood), and directly applicable in all Member States, as well as harmonized parquet, linoleum, paint, with their horizontal and vertical legal framework. glass, washable upholstery Basic requirement No. 3 – Hygiene, health and the environment [15], cushions, foam, cork, paper, relevant for used materials, demands that construction works must be fabric, and PVC (window designed and built in such way that throughout their life cycle they will frames). Most of used not be a threat to the hygiene or health and safety of workers, occu- materials are harmless, but pants or neighbours, nor have an exceedingly high impact, over their entire life cycle, on the environmental quality or on the climate during according to epidemiological their construction, use and demolition. This basic requirement is har- studies some of them may monized with the Rules on the criteria and the minimum technical re- present health risks. quirements for space and equipment of kindergartens [3] which defines that all constructional and instal ation products must be environmental- ly friendly without health risks. The majority of materials used in playrooms were wood (particle boards, plywood), parquet, linoleum, paint, glass, washable upholstery cushions, foam, cork, paper, fabric, and PVC (window frames). Most of used materials are harmless, but according to epidemiological studies some of them may present health risks [52-59]. The literature review [53,54] showed that wooden construction products and furniture as well as paints, adhesives, varnishes, floor finishes, disinfectants, clean- ing agents and other household products present the main indoor sources of formaldehyde. Paints, varnishes and cleaning agents may be the source of volatile organic compounds (VOCs) [55-57]. Linoleum has been shown to emit a series of aldehydes and fatty acids as major VOCs [60]. Various studies [55,56,58,59] have indicated that numer- ous indoor sources and insufficient ventilation often result in higher for- maldehyde and VOCs levels and may cause adverse health effects. Wi- eslander et al. [56] indicated that exposure to chemical emissions from 10 © Inštitut za sanitarno inženirstvo, 2013. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. Table 2: Evaluation of sanitary-technical conditions in 35 playrooms of 16 kindergartens, Central Slovenian region. Material Cleaning capability safety issues Natural daylight Comfort Basic hygienic conditions Playroom/ Installation of wall observed Washable Parapet Protection Window- covering up to 1.2 m parameter Floor Wall Ceiling Cove to-floor Dusty fillet wall height of radiator high. Thermal covering [m] surfaces area ratio shelves Curtain [ %] properties- warm/cool feeling to touch 1* parquet paint, wood paint - + 0.65 + 22.39 + + + 2* laminate paint paint - - 1.00** + 36.77 - + + 3 parquet paint, wood paint - - 0.61 + 34.92 - - + 4 linoleum paint wood + + 0.54 + 35.01 - - - 5 linoleum paint wood + + 0.54 + 19.48 - - + 6 linoleum paint wood - + 0.60 + 18.74 + - + Armstrong 7 linoleum paint gypsum - + 0.80** - 33.12 - + + board Armstrong 8 linoleum paint gypsum - + 0.80** - 28.15 - + + board Armstrong 9 linoleum paint gypsum - + 0.80** - 36.08 - + + board Armstrong 10 linoleum paint gypsum + + 0.90 - 23.46 - + + board Armstrong 11 linoleum paint gypsum + + 0.90 - 25.27 - + + board 12 linoleum paint, wood paint - + 0.50 + 36.29 + + + 13 linoleum paint, wood paint + + 0.40 + 21.80 + + - 14 linoleum paint, wood paint + + 0.52 + 21.02 + + - 15 laminate paint paint - + 0.55 + 18.49 - - + 16 linoleum paint paint - - 0.00 - 44.43 - + + Armstrong 17 parquet paint gypsum - + 0.60 - 25.09 - - + board 18 parquet paint paint - + 0.60 - 31.74 - + + 19 parquet paint paint - + 0.89** + 25.96 - + + 20 parquet paint paint - + 0.89** + 25.01 - + + 21 parquet paint paint - + 0.89** + 26.40 - + + 22 parquet paint paint - + 0.85** - 35.39 - + + 23 parquet paint paint - + 0.85** - 21.21 - + + 24 linoleum paint, wood paint + + 0.74** - 31.62 + - + 25 linoleum paint, wood paint + + 0.73** - 41.63 + - + 26 linoleum paint, wood paint + + 0.75** + 22.77 + - - 27* parquet paint, wood paint - + 0.60 + 9.09 + + + 28 linoleum paint, wood paint - + 0.55 + 27.44 + + - 29 linoleum paint, wood paint + + 0.90** - 39.92 + - - 30 linoleum paint, wood wood - + 0.90** - 38.42 + - - 31 linoleum paint, wood wood, steel (I beam) - + 0.90** - 46.24 + - - 32 linoleum paint, wood, wood, steel (I beam) + + 0.86** - 39.19 + - - Armstrong 33 linoleum Wood, paint gypsum + - 0.60 - 37.38 - + + board 34 rubber paint, rubber paint - + 0.00 - 35.67 + + + 35 rubber paint, rubber paint + + 0.00 - 26.24 + + + *Building was not intended for educational purposes; **Playroom is located in the first floor. International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 11 K. Kacjan Žgajnar, A. Galičič, U. Zoran e  t al. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measures indoor paint is related to asthma, and that some VOCs may cause in-flammatory reactions in the airways. Results by Norback et al. [55] suggested that indoor VOCs and formaldehyde may cause asthma-like symptoms. Used PVC materials for window frames (instal ed in play- rooms No. 1-2, No. 4-11, No. 15, No. 17-23, No. 29-32; representing 62.9 % of total playrooms) also may present an important cause of health concerns. The literature review on health concerns associated with PVC building materials concluded that PVC building material presents an important emission source of phthalates that may have ad- verse health effects [61-64]. Most exposed population is young children and certain groups of adults during occupational exposure. Various studies [63,64] have indicated that these chemicals may be endocrine disruptors and may lead to the development of asthma, al ergies, or re- lated respiratory effects. Additional y, PVC window frames are usual y The literature review on wider than wooden ones, and provide less amount of daylight [65]. All health concerns associated building materials, where there exist scientific facts for adverse health with PVC building materials effects, should be ful y eliminated, especial y in buildings occupied with concluded that PVC building sensitive population group. material presents an Hygienic and comfort issues important emission source of Rules on the criteria and the minimum technical requirements for space phthalates that may have and equipment of kindergartens [3] define that all floor coverings must adverse health effects. be solid, non-slip and should al ow effective wet cleaning. Additional y, the floor-wall junctions (cove fil ets) must be instal ed to assure easy and effective wet cleaning [3]. Floor coverings in all playrooms met the criteria, except floor coverings in playrooms No. 1-3, No. 15, No. 17-23 and No. 27 that were covered with laminate or parquet. Laminate and parquet do not al ow effective wet cleaning, disinfection and they may absorb water. Floor-wall junctions were properly instal ed in 13 play- All building materials, where rooms; among them there were 12 playrooms covered with linoleum there exist scientific facts for and 1 playroom with rubber. Floor-wall junctions were not properly in- adverse health effects, stal ed in playrooms where floors were mainly covered with parquet and should be ful y eliminated, laminate. especial y in buildings Wall coverings up to 1.2 m high must be washable and made from ma- occupied with sensitive terials that are pleasant to touch and feel warm, and with proper abra- population group. sion resistance [3]. Wall coverings were washable in 31 playrooms where wall coverings were made from waterproof paint or wooden pan- els. Wall coverings in 4 playrooms (No. 2, No. 3, No. 16 and No. 33) did not fulfil the regulated demands, because they were made from non-waterproof paint. Wall coverings in 16 playrooms were made from materials that are pleasant to touch and feel warm (wood). Wall cover- ings in 19 playrooms did not fulfil the regulated demands; they were covered with wall paint. Effective and regular cleaning contributes significantly to the prevention and control of infectious diseases. Dust deposition on playroom surfac- es may lead to bacterial growth [66]. Study [67] found a correlation between the content of organic dust in carpets and the appearance of symptoms of sick building syndrome (SBS). Additionaly, Gyntelberg et al. [68] found a significant correlation between the prevalence of Gram- 12 © Inštitut za sanitarno inženirstvo, 2013. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. negative bacteria in the indoor dust and symptoms such as fatigue, heavy-headedness, headache, dizziness and lack of ability to concen- trate, and symptoms from the mucus membrane of the upper respirato- ry tract. Dust mites and their residue found in beds, pil ows, carpets, and furniture surfaces cause al ergies [69]. Basic hygienic conditions in many playrooms were poor. 13 playrooms from overall 35 had dust de- posited on the top of shelves, 9 playrooms from overall 35 had window curtains. Safety issues In all playrooms high level of safety must be provided. Basic require- ment No. 4 – Safety and accessibility in use [15], requests that the construction works must be designed and built in such a way that they do not present unacceptable risks of accidents or damage in service or in operation, such as slipping, fal ing, col ision, burns, electrocution, in- jury from explosion and burglaries. In particular, construction works must be designed and built taking into consideration accessibility and use for disabled persons. Therefore, Rules on the criteria and the mini- mum technical requirements for space and equipment of kindergartens [3] define that all floor coverings must be solid and non-slip. All wall corners up to 1.2 m must be secured with rounded corner profiles. All Dust deposition on playroom the furniture corners and edges must be smooth and free of sharp edg- surfaces may lead to es. Heavy and high furniture must be screwed to the floor and to the bacterial growth. Study found wall [3]. All playrooms fulfil ed the safety demands. a correlation between the The required maximum height of window parapets in playrooms that content of organic dust in are located at the ground floor is 0.60 m above the ground, and mini- carpets and the appearance mum 0.90 m for playroom located in the first floor. All windows have to assure high level of safety and prevent fal ing out of windows [3]. Para- of symptoms of sick building pets in 4 out of 18 playrooms located at the ground floor did not meet syndrome (SBS). the criteria; parapets in 13 out of 17 playrooms located in the first (or higher) floor did not meet the criteria. Overall 48.6 % of playrooms did not comply with conditions. Natural daylight External environment has stimulative effect on the human body and mind. Daylight provides quality lighting, stimulates sense of sight and is an important communication between the internal and external space [65]. Several researches showed connection between natural daylight and improved learning outcomes in schools. Other positive effects of natural daylight are: better il umination, visual stimulation, improved concentration and responsiveness, faster learning, less il nesses, less dental decay (cavities), improved eyesight, increased body growth and improved immune system [65,70-72]. Natural daylight has to be provided in all playrooms. The depth of the playroom should not be more than 2.5 times height level (from the ground to the upper edge of the window); otherwise the playroom must be il uminated from two room sides. The total opening area of windows must not be less than 1/5th the floor area of the room [3]. 25 play- rooms fulfil ed the criteria for the depth of the playrooms. 10 playrooms International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 13 K. Kacjan Žgajnar, A. Galičič, U. Zoran e  t al. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measures did not meet the criteria and had room depths more than 2.5 times the height level, only 4 of them were il uminated from two room sides. Playroom No. 16 was il uminated from two room sides and had ratio 3.76. Playroom No. 34 had the worst ratio 2.80 and was not il uminat- ed from two room sides. 31 playrooms had the total opening area over 1/5 of the floor area of the room, 14 of them had the total opening area over 1/3th of the floor area of the room (No. 2-4, No. 9, No. 12, No. 16, No. 22, No. 25 and No. 29-34). Playrooms No. 5, No. 6, No. 15 and No. 27 did not meet the criteria for the total opening area of win- dows. Playroom No. 27 had the total opening area of windows 9.09 % (less than 1/11th of the floor area). Clean, double glazed windows transmit about 70 % of daylight. On the other hand, triple glazed windows, in an effort to improve thermal insu- lation, transmit barely about 50 % of daylight [65]. After observing sev- eral playrooms, we found out that 24 % of them had triple glazed win- dows. This type of glazing was noticed in playrooms with replaced windows, in an attempt to reduce energy losses, and in playrooms of the newly build kindergartens. As we know, triple glazed windows transmit less natural daylight than double glazed windows [65]. Addi- tional y, in evaluated playrooms daylight penetration was often distract- ed by inappropriate use of shading system or even by various items at- tached to the window (shaped paper, drawings etc.). Analyses of reverberation time Basic requirement No. 5 – Protection against noise, requests that con- struction works must be designed and built in such a way that noise perceived by the occupants or people nearby is kept to a level that will not threaten their health and will al ow them to sleep, rest and work in satisfactory conditions. Rules on the criteria and the minimum technical requirements for space and equipment of kindergartens [3] state that floor, wall and ceiling coverings must be made of materials that reduce noise. Rules on the acoustic insulation in buildings [41] and Technical guidelines for protection against noise in buildings [42] define that pro- tection against noise in buildings must provide actions against noise produced outside and/or in a building, actions against direct sound transmission (through air and structures), actions against equipment noise and actions against reverberation sound. Protection against rever- beration noise has to be ensured by proper instal ation of sound absorp- tive surface elements, taking into account the size and shape of the space. The reverberation time was measured in two playrooms, No. 28 and 33, and compared to calculated and optimal values (Figure 1). Most playrooms had calculated reverberation time more than two times higher than optimal time. Connection (trend) between all the calculated values is very similar, with lowest values calculated with Mil ington- Sette formula, middle values calculated with Eyring and higher values with Sabine formula. For most of the playrooms (except playrooms No. 4 and No. 17) reverberation times that were calculated with the Sabine 14 © Inštitut za sanitarno inženirstvo, 2013. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. formula are more accurate (absorption coefficients less than 0.2). It can be observed that the reverberation time values calculated using the Sabine, Eyring and Mil ington-Sette formulae significantly deviate from the measured values. Similar conclusions were found in the study by Neubauer and Kostek [46]. To compare the measured and calculated reverberation times additional analysis is needed. Measurements of reverberation time were made in the frequency range from 100 to 8000 Hz (Figure 2). Playroom No. 28 had better sound absorption at high frequencies and worse at low frequencies, and vice versa in playroom No. 33. The main reason for this is in sound absorp- tion of materials that depend on the frequency level. Some materials are better sound absorbers at low frequencies and some at high. That is why we have to be careful with the selection of materials for kindergar- tens. The data [47] showed that baby cries have a basic frequency of around 500 Hz. Child speech ranges from 250-400 Hz, adult females tend to speak at around 200 Hz on average, and adult males around 125 Hz. The average measured reverberation times for typical frequen- cies for child voice in playrooms (250 to 500 Hz) were 0.62 s for play- room No. 28 and 0.63 s for playroom No. 33 (optimal value 0.50 s). Figure 1: Calculated, measured and optimal reverberation times [s] in 35 playrooms of 16 kindergartens. International Journal of Sanitary Engineering Research Vol. 7  No. 1/2013 15 K. Kacjan Žgajnar, A. Galičič, U. Zoran e  t al. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measures Figure 2: Average measured reverberation time MEAsUREs oN THE LEVEL oF sANITARY-TECHNICAL AND [s] in the frequency range from 100 to HYGIENIC IssUEs WITH NoIsE PREVENTIoN 8000 Hz in playroom No. 28 and playroom No. 33. Analysis of 35 playrooms in 16 kindergartens in Central Slovenian re- gion showed that in many playrooms sanitary-technical and hygienic conditions did not fulfil the regulation demands. Based on the evalua- tion of real-time conditions, measures were prepared. They include ac- tions on the level of sanitary-technical and hygienic improvements, im- plication of health and environment friendly building materials as well as measures for effective noise prevention. Sanitary-technical improvements of analysed playrooms: – removal of all materials where there exists scientific proof of adverse health concerns (i.e. PVC materials), replacement with health and environment friendly alternatives (i.e. PVC window frames for woo- den window frames), – instal ation of washable wal coverings that are zero VOC and non-toxic, – wall coverings have to be made from materials that are pleasant to touch and feel warm, – instal ation of wal -floor cove fil ets and safety covers for room radia- tors in all playrooms where they were missing, – repair of parapet heights or instal ation of safety window fences, sa- fety windows, – providing natural daylight with proper size of total opening area of windows (not less than 1/5th the floor area of the room), – regular effective cleaning and maintenance. Noise prevention and control in analysed playrooms: – assuring optimal room acoustics with technical measures, including instal ation of sound acoustic elements that are hygienical y adequate. 16 © Inštitut za sanitarno inženirstvo, 2013. Analysis of sanitary-technical and hygienic conditions of Slovenian kindergartens and proposed measur es  K. Kacjan Žgajnar, A. Galičič, U. Zoran et al. For complete noise protection it is necessary to implement technical meas- Holistic approach is ures defined by TSG-1-005:2012 [42] that include protection against out- necessary for solving side noise, direct sound transmission through structures, equipment noise problems in the first stages and reverberation sound. In kindergartens it is very difficult to meet the re- of design. quirement for optimum reverberation time and at the same time avoid ma- terials that are hygienical y questionable (i.e. fabric curtain). Therefore, the selection of materials with good sound absorption and hygienical y appro- priate needs special attention. Organizational measures include implemen- tation of legislation on the level of noise protection of al users (children, staff), introduction of permanent health education of teachers, parents and children, use of less noisy toys, raising the awareness in general public, state and local authorities. Alternative measures include introduction of more quiet activities in regular work day, relaxation. All listed measures are not important only for the evaluated kindergar- tens, but also for the design, construction and renovation of buildings. At the level of the design, all basic bioclimatic principles presented in Krainer et al. [73] have to be implemented. Building envelope and con- structional complexes have to al ow optimal regulation of thermal and daylight fluxes as well as assure proper sound insulation. Holistic ap- proach is necessary for solving problems in the first stages of design. In particular, buildings must be designed and built taking into considera- tion accessibility and use for disabled persons (physical, visual, hearing, mental and cognitive disability) [15, 74-76]. Sanitary-technical condi- tions of playrooms will be further on analysed in relation to the whole building concept. Our research areas will include thermal comfort, noise, and indoor air quality issues. All the above stated is necessary to assure comfort and healthy indoor environment for children and staff. ACKNoWLEDGEMENTs Research project Municipality of Ljubljana: “Noise at kindergarten – in- formation for children, teachers and parents”, Agreement No.: 169- 19/2012-7. REFERENCEs [1] Marjanovič Umek L, Fekolja Peklaj U. Sodoben vrtec: možnosti za otrokov razvoj in zgodnje učenje. Ljubljana: Filozofska fakulteta, 2008: 22. [2] Kindergarten Act, O.J. 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