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2000
Week 36
Week 37
Week 38
Week 39
Week 40
Week 41
Week 42
Week 43
Week 44
Week 45
Week 46
Week 47
Week 48
Week 49
Week 50
2001
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Week 12
Week 13
Weeks 14-20

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The experiments continued as planned. A skimming of the air quality questionnaires showed that the carpet condition does not seem to have a significant effect on the air quality perceptions. As a matter of fact, a surprisingly big number of subjects are not particularly fond of the air quality at the cool condition without carpet when first entering the field lab. Perhaps the air seems too cold to them.

The preferred thermal state of many of the subjects was found to be “slightly warm” rather than “neutral” as first assumed. Since we do the controlling of the temperature and since we only became aware of this fact after the first week the subjects have felt a greater degree of comfort in the second week of experiments. The results should not be significantly affected by this fact since the experiments are balanced.

We found out that a few errors have snug into the distribution of tasks so that some of the subjects have gotten the same addition, multiplication and text typing task twice. This is not viewed to be critical to the outcome of the results – especially not with regard to the addition and multiplication, because it is not possible to remember the correct answers from one experiment to the other. For the text typing, however, it may be possible to recall certain text sequences. Moreover, the subjects complained of psychological strain of retyping the same text. We have to estimate what effect this has on the results. Perhaps it would be a good idea to discuss it with Thomas, who probably has experienced something similar during some of his experiments.

The thermal manikin was available from Wednesday afternoon to Friday morning. It was therefore decided to use it for clo-value and angle-factor determination after the experiments Wednesday night (10 pm). We had five conditions we wanted to expose the manikin to, and for each condition it takes one to two hours for the manikin to reach an equilibrium – in other words, we had to pull an all-nighter!

While the experiments are running - and for some hours before and after the experiments - we spend the time in the department library where our control and data logging equipment is found because it is next to the field lab. The library is a fairly small room, and quite full from books and equipment since not only we but also another group use it as control room for their experiments. The library has no windows, and the air is very warm and stale, since it is not ventilated either. It is noisy (>45 dB(A) ) and there isn’t enough room to work, either. All in all we are not quite satisfied with the indoor climate in the library belonging to the International Centre of Indoor Environment and Energy. On the other hand, time spent in there must subtract from the time that has to be spent in hell, when that time arrives.

We had intended to type in as many of the questionnaires as possible while the experiments were running. This was done for a few sessions only. We usually had enough of various tasks to keep us busy through the mornings before the experiments started. Moreover, it was difficult to concentrate in the library (see above) and working space was limited. During the experiments, one person functioned as the session supervisor, by giving the subjects instructions to the tasks, collecting questionnaires and measuring for example fingertip temperatures. He also had to monitor the temperatures at each workstation, and respond to the comfort questionnaires. This left little time to other tasks. The person not being session supervisor for that day was also present during the experiments, but had time to do other tasks. Often he spent the time relaxing, arranging food and various practical matters since the long days were tiring us down.

CLOSING REMARKS FROM THE SUBJECTS:

During the experiments the subjects often asked of the purpose of the experiments. They wanted to know what parameters were changed from time to time. We refused to tell them anything until the experiments had finished as to not affect the outcome of the results. We did, however, have some interesting talks with the subjects after their last experiment where we disclosed what the experiments were all about and they told us of their thoughts during and after the experiments. Some of these thoughts are brought here:

1. The test persons in group no. 3 believed we tried to measure their performance from time to time. However, they said that it was not necessarily the office environment that they were subjected to that determined their efficiency but rather their pre-experiment factors such at tiredness and motivation on that given day. They therefore asked us to give attention to the self-evaluation scale (0 – 100%) at the end of the experiment.

2. Subject no. 5 asked whether it we purposely made them freeze every time, but she was also the most sensitive person to cold of all 28 subjects. One of the other subjects (no. 8) also thought it often had been cold. So, cold that it was difficult to concentrate. Subject no. 7 from the same group commented that he thought it had been hot. He had, for example not used his fleece jacket for condition C (23°C), which the other two had. It shows that there is a big variation among people as to how sensitive they are to cold. However, it also shows that some of the subjects were of the opinion that we purposely made them freeze, which has some psychological implications on their performance. Studies by Wyon have shown that acceptability of the indoor environment significantly increases when people are able to control their own micro-climate.