Throw ropes come in many shapes and sizes, so choosing which one is best for your needs can be a tough decision.  There are a three different factors to use in determining which rope is good for you: diameter, length and material.

Rope Diameter
The smallest size rope for any kind of river rescue situation would have to be 5/16”.
Advantage of Small Diameter:
These ropes can be packed into very small places (ie. back of PFD, in kayak/ canoe) without taking up a lot of space.
Disadvantage of Small Diameter:
The problem with such a small diameter rope is that it is just flat out hard to hold on to. The rope tends to slide through hands easier.  There is also more chance of rope burn with a smaller diameter. These ropes are rarely used for pin or serious rescue situations.  The tensile strength of this rope does not stand up to the pressure that is applied when unpinning a boat of any size and it can be harder to hold on to.

The largest and most versatile rope size would have to be 3/8”.
A rope  of this diameter can be used for rescue and pin situations.  This diameter rope is easy on the hands of swimmers or rescuers working a z-drag.  This would have to be the guide pick for all around clothes line and rescue tool.
The rope tends to pack bulkier than the small, well-packed ropes. The rope also tends to weigh a few more ounces.

There are other sizes in between these two and some even bigger.  A rope any larger than 3/8” would manly be used on a commercial rafting trip.  They are usually yellow so easily visible in the water and will not be found in a stuff sack option, strictly a coil rope.

Most throw ropes on the market are in the 55′ to 75’ range. As a recreational kayaker, general rule of thumb is to have a rope as long as you can throw; on the other hand, when taking on more expedition style trips you may want to think about using a 75’ range or longer.

For professional river guides, it is worthwhile looking at the USDA Forest Service published requirements for a specific river before deciding what length is best for you and your job.

There are a few different types of ropes on the market, the most typical being polypro and spectra core.

Polypro –
Advantage: More user friendly on the hand of the thrower or the swimmer.
Disadvantage:  PolyPro rope is going to have less tensile strength.  This rope would not be the ideal tool for unpinning a boat or putting a static line across the river.

Spectra Core –
Advantage: Spectra has about twice the strength of polypro, it floats and has good abrasion resistance.
Disadvantage: slippery (knots slip), does not handle shock loads well, doesn’t show much elongation before it breaks (<4%) which means it won’t give you much warning before failure.

Once you decide on a rope for you, there are a couple of follow-up rules:

1. Carry a rope. Have a knife. No exception.
2. Learn how to throw your rope. And practice throwing every once in a while.
3. Always take care of your rope.  It is advisable to sometimes empty your rope from its stuff sack and air dry it. If you leave wet line buried under other gear, it may become moldy and knotted, which can weaken the line.  When you pull it out to dry, inspect the rope for any signs of wear or degradation.

Finally, for your own safety, make sure your buddies carry ropes. In most situations you carrying a rope will not do you any good.

For more in-depth beta on rescue gear, check out Risk & Kayaking: The Three Part Series.