Question

By the end of the day, a 45 ft x 25 ft x 8 ft office has a carbon dioxide air level of 1,100 ppm. Determine the time in hours necessary to reduce this concentration to ambient levels (approximately 325 ppm) assuming 20% of the return is "fresh" makeup air and there are two air changes per hour.

Answer 1

The total hours that are necessary to reduce carbon dioxide level to at least 325 ppm are 4 hours.

How does carbon dioxide concentration change over time?

First hour:

• 1,100 - 20 %
• 1,100 - 220 = 880

• 880 - 20%
• 880 - 176 = 704

Second hour:

• 704 - 20%
• 704 - 140.8 =663.2

• 663.2 - 20%
• 663.2 - 132.64 = 530.56

Third hour:

• 530.56 - 20%
• 530.56 - 106.112 = 424.44

• 424.44 - 20%
• 424.44 - 84.88 = 339.55

Fourth hour:

• 339.55 - 20%
• 339.55 - 67.91 = 271.64

Learn more about carbon dioxide in: brainly.com/question/3049557

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