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The studies of office chair constructions have identified differences in perception of comfort provided by different types of seats. Four seat constructions and the comfort provided to the users were compared by means of subjective indicators. After a two-day sitting on each of the studied chairs, the subjects scored their perception of comfort and discomfort, using the questionnaire with 17 statements. Unlike most similar studies, subjects evaluated seats on their own work places and in the environment to which they are accustomed. Constructional forms of the seat and materials that contributed more to the sense of comfort by minimizing fatigue and pains developed by sitting were determined. Results have shown that the chair with a net is significantly more comfortable than other chairs. The chair with molded PUR foam is significantly more comfortable than the chair with springs, but statistically it does not differ significantly from the chair with slabstock PUR foam. It has been concluded that the chair with a net got higher scores, which might be attributed to its frame construction and the absence of a hard base under the sitting surface.

The studies of office chair constructions have identified differences in perception of comfort provided by different types of seats. Four seat constructions and the comfort provided to the users were compared by means of subjective indicators. After a two-day sitting on each of the studied chairs, the subjects scored their perception of comfort and discomfort, using the questionnaire with 17 statements. Unlike most similar studies, subjects evaluated seats on their own work places and in the environment to which they are accustomed. Constructional forms of the seat and materials that contributed more to the sense of comfort by minimizing fatigue and pains developed by sitting were determined. Results have shown that the chair with a net is significantly more comfortable than other chairs. The chair with molded PU foam is significantly more comfortable than the chair with springs, but statistically it does not differ significantly from the chair with slabstock PU foam. It has been concluded that the chair with a net got higher scores, which might be attributed to its frame construction and the absence of a hard base under the sitting surface., Istraživanjem konstrukcija uredskih stolica utvrđene su razlike u osjećaju udobnosti sjedenja na različitim sjedalima. Uspoređene su četiri konstrukcije sjedala i njihove udobnosti za korisnika, i to na temelju subjektivnih pokazatelja. Ispitanici su nakon dvodnevnog sjedenja na stolici ocjenjivali osjećaj udobnosti ili neudobnosti odgovarajući na upitnik sa 17 ponuđenih tvrdnji. Za razliku od većine sličnih istraživanja, ispitanici su ocjenjivali sjedala na svojim radnim mjestima i u okolini na koju su naviknuli. Ispitivanjem su određeni konstrukcijski oblik sjedala i materijali izrade stolica koje pridonose osjećaju veće udobnosti time što minimaliziraju osjećaj zamora i pojavu bolova pri sjedenju. Rezultati su pokazali da je stolica s mrežom znatno udobnija od ostalih. Stolica s hladno lijevanom PUR spužvom mnogo je udobnija od stolica s oprugama, ali se statistički ne razlikuje od stolica s rezanom PUR spužvom u sjedalu. Zaključeno je da je stolica s mrežom najbolje ocijenjena zbog njene okvirne konstrukcije i zato što ispod površine za sjedenje nema tvrde podloge.

Thermal comfort is related to human physiological reactions. In order to maintain a constant internal temperature, the human body must dissipate heat in a warm climate, and prevent heat losses in a cold climate. The overall sensation of comfort accompanies the warmest part of the body in a warm environment and the coldest one in a cold environment. Chair design and clothing may affect the difference in sensitivity between certain parts of the body, that is, they may affect thermal comfort. This research focused on subjective sensation of warmth and moisture while sitting on offi ce chairs. The subjective method of evaluating thermal discomfort is based on ISO7730:2005 standard, according to which a questionnaire was made for this research. Six subjects took part in the research. They were sitting on fi ve different offi ce chairs as they performed their usual jobs in controlled conditions. From the point of view of the evaluation of the sensation of warmth, all chairs were evaluated neutrally. The sensation under the buttocks and thighs was reported to be somewhat warmer, while the sensation on the back was reported to be somewhat colder, which was affected by the design of the back of the chair. No correlation has been proven between the actual temperature and moisture measurements and subjective evaluations of thermal comfort, in spite of a number of direct links. The use of the present method offers the possibility of further research into this subject, which would prove more thoroughly a correlation between design and construction solutions of office chairs and the comfort perceived by sitting persons.

Thermal comfort is related to human physiological reactions. In order to maintain a constant internal temperature, the human body must dissipate heat in a warm climate, and prevent heat losses in a cold climate. The overall sensation of comfort accompanies the warmest part of the body in a warm environment and the coldest one in a cold environment. Chair design and clothing may affect the difference in sensitivity between certain parts of the body, that is, they may affect thermal comfort. This research focused on subjective sensation of warmth and moisture while sitting on offi ce chairs. The subjective method of evaluating thermal discomfort is based on ISO 7730:2005 standard, according to which a questionnaire was made for this research. Six subjects took part in the research. They were sitting on five different office chairs as they performed their usual jobs in controlled conditions. From the point of view of the evaluation of the sensation of warmth, all chairs were evaluated neutrally. The sensation under the buttocks and thighs was reported to be somewhat warmer, while the sensation on the back was reported to be somewhat colder, which was affected by the design of the back of the chair. No correlation has been proven between the actual temperature and moisture measurements and subjective evaluations of thermal comfort, in spite of a number of direct links. The use of the present method offers the possibility of further research into this subject, which would prove more thoroughly a correlation between design and construction solutions of office chairs and the comfort perceived by sitting persons., Toplinska ugodnost povezana je s fiziološkim reakcijama osoba. Kako bi zadržalo stalnu unutarnju temperaturu, tijelo mora oslobađati toplinu u toploj klimi, a sprečavati gubitke topline u hladnoj klimi. Ukupan osjećaj udobnosti prati najtopliji dio tijela u toplom okružju i najhladniji u hladnom okružju. Dizajn stolca i odjeća mogu utjecati na razliku u osjetljivosti između nekih dijelova tijela, odnosno mogu utjecati na toplinsku ugodnost. U radu su istraživani subjektivni osjećaji topline i vlage pri sjedenju na uredskim radnim stolcima. Metoda subjektivne procjene toplinske udobnosti temelji se na normi ISO 7730:2005, prema kojoj je napravljen upitnik za ovo istraživanje. U ispitivanju je sudjelovalo šest ispitanika koji su sjedili na pet različitih uredskih stolaca za vrijeme obavljanja uobičajenih radnih zadataka u kontroliranim uvjetima. Sa stajališta procjene osjećaja topline, svi su stolci ocijenjeni neutralno. Ispod stražnjice i bedara osjećaj topline procijenjen je nešto većim, a osjećaj na leđima hladnijim, na što je utjecao dizajn naslona. Korelacije realnih mjerenja temperature i vlage sa subjektivnim procjenama toplinske udobnosti nisu dokazane, unatoč nekolikim izravnim poveznicama. Rad i prikazana metoda otvaraju mogućnost za daljnja istraživanja te problematike kojima bi se detaljnije dokazala korelacija između oblikovno-konstrukcijskih rješenja radnih stolaca i udobnosti sjedenja na njima.

Konstrukcije sjedala i naslona uredske stolice kao predmeta čovjekove radne okoline važni su u njezinom konačnom rješenju jer su to elementi koji su izravno i usko povezani s ljudskim tijelom. Sjedeći je položaj najčešći radni položaj modernog čovjeka u industrijski razvijenom svijetu. Neovisno o vrsti posla, pravilan i fiziološki ispravan sjedeći položaj smanjuje zamor pri radu i opterećenje kralješnice, a odgovarajući povoljan položaj pri sjedenju uvelike pridonosi povećanju koncentracije i radnog učinka. Sjedeći radni položaj moguće je razmatrati usklađivanjem antropometrijskih veličina s oblikom sjedala i naslona ili, mehaničkim pristupom, utvrđivanjem odnosa između korisnika i kvalitete sjedala, pri čemu velik utjecaj ima indeks udobnosti. Indeks udobnosti stolice kao jedan od pokazatelja udobnosti sjedenja proizlazi iz mehaničkih svojstava promatrane stolice. U radu su prikazani rezultati tzv. mehaničke udobnosti koju stolica može pružiti korisniku. Rezultati određivanja udobnosti sjedenja na uredskim radnim stolicama prikazani su indeksima udobnosti stolica dobivenih iz elastičnih svojstava materijala sjedala i stolice prema tehničkoj specifikaciji HRS ENV 14443., Construction of the seat and back of the office chair, as an actual object of the human working environment, is important in its final design since these are the elements that are in a direct and close contact with human body. The sitting position is the most frequent working position of the modern man in the developed world. Independently of the type of work, a sound and physiologically correct sitting position diminishes fatigue during work and strain of the spine, and suitable posture during sitting significantly contributes to the increase of concentration and efficiency. Sitting as a working position can be examined through coordination of anthropometric sizes and form of the seat and back, or mechanically, by determining the relation between the user and the seat quality, where the comfort index or support factor has a great infl uence. The comfort index as one of the factors of sitting comfort is the result of mechanical characteristics of the observed chair. This paper shows the results of ‘’mechanical comfort’’ that the chair can offer to the user. The results of determining the seat comfort on office chairs are featured through comfort index obtained from elastic characteristics of materials in the seat, but also of the chair itself according to Technical Specifications HRS ENV 14443.

Dugotrajno sjedenje na neprikladnim stolicama koje nedovoljno pridržavaju tijelo i uzrokuju nelagodu i umor rezultira neudobnošću sjedenja. Istraživanjem konstrukcija uredskih stolica utvrđene su razlike u osjećaju udobnosti sjedenja na različitim vrstama sjedala. Istodobno je istraživan i utjecaj nekih ljudskih osobina i obilježja na osjećaj udobnosti. U radu su prikazani rezultati provjere statističke značajnosti razlika u subjektivnim procjenama udobnosti/neudobnosti s obzirom na spol, dob, visinu i masu ispitanika, zdravstvene tegobe i navike križanja nogu tijekom sjedenja, i to na četiri različite konstrukcije sjedala. Istraživanja su provedena na 36 ispitanika i sa 16 stolica. Ispitanici su nakon dvodnevnog sjedenja na stolici ocjenjivali osjećaje udobnosti/neudobnosti uz pomoć upitnika i odgovarajući na pitanja o postojanju određenih navika sjedenja i zdravstvenih tegoba. Razlike u procjenama među skupinama ispitanika provjerene su pomoću t-testa za neovisne uzorke. Istraživanje je pokazalo da ne postoje statistički značajne razlike testiranih varijabli i osobina ispitanika, ali da postoje neki trendovi., Prolonged use of anthropologically and ergonomically unsuited office task chair can cause discomfort and problems. The study about construction of office task chairs has shown differences of subjects feelings in the sitting comfort provided by various types of seating fillings. At the same time it was researched influence of some human characteristics on comfort feeling. Paper presents statistically significant differences in subjective evaluation of comfort/discomfort on four different seat constructions regarding to gender, age, height and mass of subjects, health problems and crossing legs habits during sitting. The study included 36 subjects and 16 chairs. After two days use of the chairs the subjects assessed their feeling of comfort and discomfort by ticking statements of the questionnaire about subsistence of specific sitting habits and health problems. Differences in evaluation among subject groups are checked with t-test for independent sample. Study showed no significantly differences in tested variables and subjects characteristics, but there are some trends.