please keep in mind that i am NOT saying that you shouldn't be careful when handling R123. but some people want everyone to think that this stuff is poison. at the end of the day, this refrigerant doesn't require any different handling techniques than any other refrigerant from a safety standpoint, an EPA standpoint or a good practices standpoint. do you need to have lower ppm setpoints for your refrigerant monitors? sure. but that is for long term exposure safety. in the short term (refrigerant handling, spills, etc), you handle R123 the same as any other refrigerant.
How to make the perfect "Half-Hitch" knot or any other boyscout knot in 3 easy steps...
1. Remove your meter leads from the meter and very carefully return them to their storage case or bag.
2. Wait 2 seconds
3. Very carefully remove your meter leads from their storage place and enjoy your new knot!