room size required for sleeping in closed room.

 one person breaths 12 time per minute on average.

per breath he takes 0.5 ltr of air.

per minute vollue = 0.5X12 = 6 Ltr

Per Hour Vollume = 6X60 = 360Ltr

for 8 hours = 8X360 = 2880 Ltr

if one person has to sleep in closed room, then the vollume must be 2880Ltr.

1000 cubic cm = 1ltr . 

1 cubic mtr = 1000 Ltr

2880 Ltr = 2880 cm3 2880X1000 =  2880000 cm3

length and width for human = 7feet X 3feet = 210cmX90cm = 18900 cm

to find hight = 2880000 /18900 =152.4 cm = 152.4/30 = 5.1 feet

now required measurements are = 7 feet Length X 3 feet width X 5 feet Height 

measure here.

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