r/searchandrescue • u/Whatthedillyo85 • 25d ago

CMC RESCUE Carabiner strength question

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I’m having a hard time figuring out how strong this is.

What would it be rated to in poundage?

Thank you ahead of time for the assistance.

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u/F1r3-M3d1ck-H4zN3rd 25d ago

kN and pounds measure different things, so you'll never have a perfect conversion. Newtons measure force, while pounds measure weight - but you can say that with a static load a 255lbs weight create 1kN of force - though things get more complex when there is dynamic loads. Drewts86 already gave a good explanation, I thought I would just throw in the reason that you are having trouble finding an exact conversion.

16

u/LazerBear924 Fire/Mountain Rescue, CO 25d ago

Thats not accurate. Weight is a force, just a very specific type of force caused by gravity acting perpendicular to the Earth.

Pounds are the US customary system unit for force. Engineers use pounds to measure forces in any dimension as needed in structural design, as forces are forces. Source: am a licensed civil engineer and rope rescue tech.

2

u/Useful_Resolution888 25d ago

Wow, you genuinely still use imperial as an engineer in the US? I'm an engineer in the UK and there's still a few old boys around who think in thou rather than mil, but they're very few and far between now. Most of the American kit that we buy is metric these days and I just assumed that technical industries and engineers there had made the shift already. It must throw up all sorts of complications working with any equipment from outside of the country.

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u/LazerBear924 Fire/Mountain Rescue, CO 22d ago

I work in civil engineering and US customary is the way we design basically everything in public works. There was a push for metrication in the 90s that was basically just converting all the drawings to metric (but still using the USCS measurements/unitized things, so a drawing would call for #7 rebar as 22.225 mm diameter instead of designing with 20mm or 25 mm rebar).

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u/Useful_Resolution888 22d ago

About 20 years ago I worked with an older guy who was a young engineer in the 70s. By that point everything was metric but some of the older generation refused to convert. The first company he worked at had an old boy that looked after the stores and would refuse to issue metric bar unless you asked for it using the precise imperial measurement - eg M20 would be 787 thou. He just had to learn all of the common sizes!

I grew up in a metric world and the idea of using anything else just seems mad to me. I guess the US has a big enough manufacturing base that you can be self supporting without much international trade.