Evaluation of indoor environmental quality (IEQ) in higher education classrooms: a case study of SQU classrooms
Fatema Shamis Saif Al-Akhzamiyah , Hanan Al-Khatri, Saleh Al-Saadi
كلية الهندسة-جامعة السلطان قابوس · عمان
Indoor environmental quality (IEQ) is a holistic term for the combination of factors,namely thermal conditions (TC), visual conditions (VC), acoustical conditions (AcC),and indoor air quality (IAQ). It is considered an important indicator of the occupants'health, well-being, and productivity, especially in educational buildings wherestudents spend most of their time indoors. Although Oman is located in a region withextreme climatic conditions, no published research, up to the knowledge of theresearcher, addresses the evaluation of indoor environmental quality in educationalinstitutions. In an attempt to fill this gap of knowledge, this thesis aims at evaluatingIEQ in selected classrooms at Sultan Qaboos University (SQU), Oman, exploring theoccupants' perception of IEQ and investigating the current IEQ conditions in theclassrooms. A mixed-method approach was followed to carry out the researchinvolving subjective and objective assessments. The former were a self-reportedquestionnaire of students' sensation, satisfaction, and preference. The latter involvedmeasuring environmental variables using specialized instruments. The survey wascarried out in nine classrooms with the participation of 475 students.The IEQ results revealed that the thermal sensations were clustered between neutral tocool, which differs slightly from the comfort range specified by ASHRAE database.The visual sensations were clustered between slightly dim and slightly bright, whichis considered within the comfort range. Regarding the acoustic condition, thesensations clustered between slightly noisy and quiet, and this range is the comfortrange. Considering the students' perceptions of indoor air quality, the sensations' votesclustered between slightly bad to good. Most of the students perceived air quality asgood. Thus, the classrooms are comfortable based on the students' point of view.Based on the objective measurements, the measured variables were incompliant withcomfort ranges specified by the international standards. This indicating that theinvestigated classrooms are uncomfortable.With the increasing interest in IEQ and its influence on occupants' satisfaction andcomfort inside buildings, a great focus was invested in allocating a weighting schemefor IEQ by identifying the relative importance of each individual factor. This studyproposed an original IEQ weighting scheme based on the opinion of the facultymembers of the College of Engineering and the students. Considering the resultingIEQ weights from faculty members of the College of Engineering and the students, itobserved similar ranking order for the four factors. The results of this study are usefulin enhancing the student's educational experience in SQU. Further, they can be usedas a reference for further investigations of IEQ for educational buildings, especially inhot climates. Moreover, the appropriate use of the IEQ weighting scheme can guidearchitects and engineers to design comfortable and energy-efficient buildings.