What size chain for handline

Planning to add a handline for a steep and loose section of trail. What size chain are people using for this? Is 1/8" too skinny?

I typically see steel cable or stat rope used for hand lines.  

Maybe look at the working load limit (WLL) of the potential materials to make a more educated decision?

Over building your hand line will alway be better than "should be OK"

I have used 5/8" polypropylene. It comes in a tan color that isn't very visually distracting in most environments. It is fairly inexpensive and seems to hold up well to the weather. The diameter is thick enough to get a good grip.

 I source it from e-rigging.com. 

Thanks for the replies. Working Load Limit of 1/8" chain is 375 lbs. The next step up is 3/16" with a WLL of 800 lbs. Seems like both options are strong enough, the thicker chain might feel nicer to grab. 

Thanks for the suggestion of polypropylene... I'm fairly set on using metal for holding up to the elements. I will look into steel cable as well.

Something like this seems to be a popular solution. 

The WLL usually has a safety factor of 1 to 5 before breaking.  I am assuming this is standard hardware store chain.

At a 375lbs WLL 2 climbers with packs could easily meet that and in a fall situation will certainly be above that.  Multiplication of forces can at play depending on how it is anchored.  

A another factor for consideration is narrow chain can be difficult to attach to a bolt hanger.  The quick links that fit over standard bolt hangers do not fit through most narrow chains.

Even with the heavier chain you may want to dry fit your components before hauling them to the wall.

Check with your local climbing gym, lots of times they will give you retired ropes for projects just like this.   If you’re flexible it’s a great option.

Definitely put up something that’s big enough to grip and would suggest you stay away from narrow gauge wire rope.   

https://www.e-rigging.com/three-eighths-X-200-foot-Coated-Galvanized-Cable

We use vinyl coated cable at my work. It's easier on the hands.  Don't go too thin or it will be bad to grip. I.e. you'd be better off using rope than 1/4" cable.  How necessary is the installation?