2015_07_01 Initial testing (Near Holworthy St, Cambridge, MA 02138)

Today was my first field measurement. It was very exciting but at the same time I was worried that people might notice it too much and ask too many questions about the testing. Luckily, they did show interest but not too much.

I had 28 different set of data from 19 different locations. Some values, including pressure and Oxygen level, remained almost constant or had very little variations between locations. Significant differences were shown in amount of light, humidity, temperature, altitude, height of ceiling, and propane and Ethanol level.

The light was detected the most outside. Around 4 PM, the amount of light was well above 11,000 lux. Subway had 113.8 lux to 146.1 lux. Different subway stations showed a significant difference in light. Harvard station had 159.22 lux, Central square had 174.5 lux, and Kendall square 54.36 lux, which was the darkest among three.

Humidity seemed to be higher around plants. All three subway stations had about 55% humidity. People feel pleasant between 40% and 60% humidity, so subway stations seem to meet that pleasant level. The humidity level was significantly low at a clothing store (Urban Outfitters) as 32.6%. For more pleasant shopping, the store would need to raise the humidity level.

Outside temperature around 4 PM was about 29oC. Subway stations were about 27oC. A grocery store (Star Market) showed the lowest temperature which was 24.68oC.

Stations showed lower altitude, around 56m, compared to other locations. Harvard square station was the lowest among the three.

Propane Ethanol level seems to be high around plants. Porch, Harvard park, and Harvard which were surrounded by plants had high Propane Ethanol level compared to other locations.

Three subway stations, which were my main experiment locations didn’t show any significant difference between each other. I see several discrepancies in the same station, so there is a possibility of not consistent measurement. To get more accurate measurements, I need to keep the environment as consistent as possible. For example, I should take into account if I am standing under a light source or not, how many seconds have passed after bus or subway door had closed, and even number of people. I should be more aware of the variants next time I take measurements.