For what it is worth, 20 years ago at at another institution, waste ClF3 was disposed of by removing the waste trap, freezing the waste reagent in LN2, opening the valve, and letting the gas exapand through a box filled with concrete mix. I assume the main neutralizing reaction was to form CaF2, which may be more inert than KF. Obviously, in this day and age, you will want to check with your risk management folks. Otherwise you may be rolling the dice. -- ******************************** Steve Nelson Dept. of Geology S389 ESC Brigham Young University Provo. Utah 84602 voice: 1-801-422-8688 lab: 1-801-422-5124 FAX: 1-801-422-0267 CARPE CARP: seize the fish ********************************