Lucite Tubing - Burst Pressure to Working Pressure

If it is not designed to a piping code simply use an appropriate factor of safety.

For example:

• If the product is non-toxic/corrosive, low temperature/pressure, non-flammable (perhaps water) and the risk of failure and pressure fluctuations is low you may find that dividing the bursting pressure by 1.5 would be an appropriate operating pressure.
• However, if the product is toxic/flammable/corrosive, and/or the tubing is subjected to thermal/environmental degredation, etc. You may find that you want to divide the bursting pressure by 3 (or more)

Clearly the safety factor is of prime importance and should be selected by great experience and judgement (and again this is if the tubing is not to be designed to a code)

well done #1