Deck General · Cordage & Line
A 3-inch circumference manila line has a breaking strength of approximately 9,000 lbs. What is its safe working load (SWL)?
- A4,500 lbs
- B3,000 lbs
- C1,800 lbs✓ Correct
- D900 lbs
Explanation
The standard safety factor for fiber line is 5:1, meaning SWL = breaking strength divided by 5. 9,000 / 5 = 1,800 lbs. Using 1/2 or 1/10 of breaking strength would over- or under-load the line; 1/5 is the accepted deck seamanship standard.
Authority: Deck Seamanship (USCG deck topic)
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