Shamila Haddad

Revisiting thermal comfort models in Iranian classrooms during the warm season

ABSTRACT The validity of existing thermal comfort models is examined for upper primary school children in classroom settings. This is of importance to enhance productivity in the learning environment and to improve the control of artificial heating and cooling, including the potential for energy savings. To examine the thermal perceptions of children aged 10–12 years in non-air-conditioned classrooms, three sets of field experiments were conducted in boys’ and girls’ primary schools in Shiraz, Iran. These were undertaken during regular class sessions covering cool and warm conditions of the school year, polling responses from 1605 students. This paper illustrates the overall methods and reports the results of the warm season field survey (N = 811). This investigation suggests that predicted mean vote-predicted percentage of dissatisfied (PMV/PPD) underestimates childrens actual thermal sensation and percentage dissatisfied in the investigated classrooms. The analysis shows that sampled children may be slightly less sensitive to indoor temperature change than adults. The upper acceptable temperature derived from childrens responses corresponding to mean thermal sensations of +0.85 is 26.5°C, which is about 1°C lower than the ASHRAE upper 80% acceptability limit. This implies that sampled children feel comfortable at lower temperatures than predicted by the ASHRAE Adaptive model during the warm season.

Application of adaptive thermal comfort methods for Iranian schoolchildren

ABSTRACT Recent studies in primary schools highlight a need to develop the adaptive comfort model for schoolchildren in classrooms. This study investigates the application of the principal methods underlying the adaptive comfort theory for children relating thermal comfort indoors to the prevailing mean outdoor temperature. Children’s sensitivity to indoor temperature change are examined using data from a field study conducted in Iranian schools. This sensitivity is used to estimate the comfort temperatures in classroom situations with a minimum level of adaptation. Different metrics for the outdoor climate are employed to understand an expression of the climate which best predicts children’s comfort temperature. A sensitivity analysis is performed to derive the relation between indoor comfort and the climate that gives rise to the strongest correlation coefficient. Although the basic adaptive comfort relationships are applicable for children, the exponential method to calculate the prevailing mean with lower decay values leads to higher correlation with children’s comfort temperature. The slope of children’s comfort equation in relation to outdoor temperature is shown to be shallower than those of adults. Results indicate that children are more sensitive to temperature change within a single school day than across the overall survey period of several days.

Designing activity-based workspaces: satisfaction, productivity and physical activity

ABSTRACT Activity-based working (ABW) provides office workers with a variety of indoor workspaces purposively designed to accommodate different tasks. Despite an increased use of ABW, studies focusing on its impact and the resultant office design are yet to follow suit. This paper addresses this knowledge gap by providing empirical evidence from studies conducted before and after relocation from contemporary open-plan offices to ABW spaces. Results from post-occupancy evaluation (POE) surveys (n = 896 responses), spot measurements of indoor environmental quality (IEQ) and step-count monitoring (one case study; n = 20 participants) before and after relocation are reported. A total of 10 workspaces participated (six combi and four ABW) in this study. Design features were documented and analyzed. While there were limited differences in the measured IEQ conditions between office layouts investigated here, ABW workspaces yielded significantly higher satisfaction results on key IEQ dimensions, perceived productivity and health. Office layout was also found as a significant (or nearly significant) predictor of occupants’ lightly active and sedentary time but did not affect occupants’ daily step counts and distance they travelled. These results highlight the significance and impact of office layout and human-centred approach to design on occupants’ satisfaction, perceived productivity and incidental physical activity opportunities.

Time series analysis of ambient air-temperature during the period 1970–2016 over Sydney, Australia

Providing evidence of potential changes in the climate has become increasingly important as it is the first step towards adopting mitigation and adaptation measures and planning for urban resilience. In this study a statistical analysis of the ambient air temperature time series over Sydney, Australia during 1970-2016 has been carried out with the aim to investigate potential changes towards higher temperatures. The dataset has been statistically analyzed using different techniques, concluding that the investigation should be performed on a monthly basis. A persistence analysis was conducted using different statistical approaches to investigate the dependence between consecutive monthly and daily ambient air temperature values. A trend analysis of the ambient air temperature and degree days time series has been conducted using linear regression to estimate the linear trend (slope) and its statistical significance (using a Student-t-test) and the Kendall-Mann test to identify the time at which the tendency starts to occur as well as the time after which it becomes statistically significant.