The MINIMUM required for backbone floor to floor pathways is five (5) sleeves each being 103 mm (four trade size) in diameter What increase in usable floor space should another 103 mm (four trade…

Question

Options

• A=929 m2 (10,001 ft2)
• B=1858m2 (20,001 ft2)
• C=3716 m2 (40,001 ft2)
• D=4645 m2 (50,001 ft2)

• A
  3% (1)
• B
  12% (4)
• C
  82% (28)
• D
  3% (1)

Explanation

According to BICSI and TIA-569 standards, each additional 103mm (4-inch trade size) sleeve added beyond the minimum five supports an additional 3716 m2 (40,001 ft2) of usable floor space, making option C correct. Option A (929 m2 / 10,001 ft2) is wrong because it represents a much smaller increment used in different pathway calculations, not the per-sleeve floor space ratio for backbone conduit. Option B (1858 m2 / 20,001 ft2) is exactly half the correct value and does not correspond to any recognized sleeve-to-floor-area ratio in the standard. Option D (4645 m2 / 50,001 ft2) exceeds the correct value and would misrepresent the capacity added by a single additional sleeve.

Memory tip: Link the "4" in 4-inch (103mm) trade size to "40,000" square feet -- a 4-inch sleeve adds roughly 40,000 ft2 (3716 m2) of supportable floor area, so the numbers share the same leading digit.

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