Field Measurement
In this research the indoor air temperature was measured with HOBO data loggers in the cold period of February 2011 for one week , which included a survey day . The measurements assessed thermal conditions of the classrooms before the exam period and winter holiday ( Fig . 2 ).
Temperature ° C
24 19 14 9 4 -1 -6
02 / 02 / 2011 00:02 02 / 02 / 2011 04:02 02 / 02 / 2011 08:02 02 / 02 / 2011 12:02 02 / 02 / 2011 16:02 02 / 02 / 2011 20:02 02 / 03 / 2011 00:02 02 / 03 / 2011 04:02 02 / 03 / 2011 08:02 02 / 03 / 2011 12:02 02 / 03 / 2011 16:02 02 / 03 / 2011 20:02 02 / 04 / 2011 00:02 02 / 04 / 2011 04:02 02 / 04 / 2011 08:02 02 / 04 / 2011 12:02 02 / 04 / 2011 16:02 02 / 04 / 2011 20:02 02 / 05 / 2011 00:02 02 / 05 / 2011 04:02 02 / 05 / 2011 08:02 02 / 05 / 2011 12:02 02 / 05 / 2011 16:02 02 / 05 / 2011 20:02 02 / 06 / 2011 00:02 02 / 06 / 2011 04:02 02 / 06 / 2011 08:02 02 / 06 / 2011 12:02 02 / 06 / 2011 16:02 02 / 06 / 2011 20:02 02 / 07 / 2011 00:02 02 / 07 / 2011 04:02 02 / 07 / 2011 08:02 02 / 07 / 2011 12:02 02 / 07 / 2011 16:02 02 / 07 / 2011 20:02 02 / 08 / 2011 00:02 02 / 08 / 2011 04:02 02 / 08 / 2011 08:02 02 / 08 / 2011 12:02 02 / 08 / 2011 16:02 02 / 08 / 2011 20:02 02 / 09 / 2011 00:02 02 / 09 / 2011 04:02 02 / 09 / 2011 08:02 02 / 09 / 2011 12:02 02 / 09 / 2011 16:02 02 / 09 / 2011 20:02 02 / 10 / 2011 00:02
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Time |
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S |
N |
Outdoor |
Minimum Comfort |
Figure 2 : Measured indoor air temperature in Classroom N and S for one week in February 2011
Based on the field measurement results , the mean indoor air temperature was less than 21 ° C in Classroom S and around 23 ° C in Classroom N during the February field study experiment , which slightly fell within Heidari ’ s ( 2010 ) defined comfort zone ( Eq . 1 ). Heidari ’ s defined comfort zone was based on a decade of thermal comfort field studies on Iranian people in the residential and office buildings in fifteen cities and in four different climatic regions of Iran ( Heidari 2010 ). It showed that the occupants were able to tolerate a wide range of temperatures , covering more than 14K in the hot season and 7K in the cool season . He cited that , in the hot and dry climate of Iran , people can make themselves comfortable between 16.5 ° C and 22 ° C in the cold season and between 28 ° C and 34 ° C in hot seasons , by adjusting their clothes , activity and air velocity ( Heidari 2010 ). To identify the indoor comfort temperature ( T ) in the case study school building and to predict the initial comfort temperature ranges , the following equation ( eq . 1 ) was used , based on Heidari ’ s ( 2010 ) predictions . T is the monthly mean outdoor temperature .
T = 17.80 + 0.30 T ( Heidari , 2010 ) ( 1 )
Moreover , in this study , the mean radiant temperature was assumed to be equal to the indoor air temperature in the measured classrooms . According to Fanger ( 1973 ) and Santamouris ( 2008 ), when the occupants have sedentary activity less than 1.5 met and the air velocity is below 0.1 m / s , or the air is still in the indoor environment , the mean radiant temperature can be assumed to be equal to the indoor air temperature ( Santamouris 2008 ; Fanger 1973 ) which was the condition in this study .
Questionnaire Survey
The questionnaire-based survey was conducted in classrooms S and N , while the indoor air temperature was measured with HOBO data loggers . The questionnaire survey was carried out on the 9th Feb 2011 . Around 45 questionnaires were distributed to the students in two classrooms and the students were asked to fill in the questionnaires regarding their thermal sensations and based on the 7-point ASHRAE scale ( ASHRAE 2004 ) and 3-point Mc-Intyre scale ( McIntyre and Gonzalez 1976 ). The results of the questionnaire survey indicated that more the majority of the students ’ responses fell into the central three categories of the ASHRAE scale , slightly cool ( -1 ), neutral ( 0 ), and
752 ZEMCH 2015 | International Conference | Bari - Lecce , Italy