I agree with Silke and Tojo on this one. Their points are right on target.

I bought two sets of nipple clamps for an experiment.
One was so nasty, neither I nor my test subject could wear them for more than a few seconds. The others were so loose, they could hardly be felt at all.

Clothes pins or pegs can be the same. Not all are alike, not even from the same carton.

The tighter the pin/rope/clamp the more chances of losing blood flow to the area. The looser, the less chances and the longer the playtime.

Who's responsible? Both of you.

Before attempting any type of play with ropes, pins, pegs, clamps, etc., it's best to do your homework. Thank goodness, there are plenty of articles on the Internet to help. Cause when you visit "Dom Depot" they certainly don't have instructions for alternate uses of household objects.

If you are the type of sub who easily looses track of time or drifts into subspace, then let your dom know. Like anything else, how long you wear anything can be a negotiated limit that should be respected.

In the library, there are stories of subs wearing ropes or clamps for hours, they are strung upside down for long periods of time, etc., etc. etc. And don't even get me started on things like inserting anal toys or objects without lubricant of any kind. Grrr. Then there's reality.

The lovely Jadetiger has a couple of threads detailing things she tried with some of her doms and pets. They are worth a read as she journals her experiences and discovered limitations.

Under New Management or Meeting A New Dom
http://www.bdsmlibrary.com/forums/showthread.php?t=3220

Jade's Master's thread
http://www.bdsmlibrary.com/forums/showthread.php?t=2857

This one is the flip side:
Mistress Jade's Thread
http://www.bdsmlibrary.com/forums/showthread.php?t=2965

Let's get back to the responsibility thing. Lack of knowledge does not mean out of line. Mistakes happen and not everyone knows everything.

Remember the old saying:
Burn me once, shame on you.
Burn me twice, shame on me.

I believe that playing risk aware can help prevent injuries and keep both partners happy and healthy.

Ruby