14C Extended Range Quenched Standards for testing scintillation counter performance. Revvity provides 3H and 14C standard sets for testing Revvity's scintillation counter performance, as well as internal standard capsules for preparing your own 3H and 14C standard solutions. The unquenched and quenched standard sets are manufactured at Revvity in controlled environments. They are prepared gravimetrically from NIST traceable solutions. After preparation, all standards are QC tested with calibrated counting systems at Revvity. Unit size 7 ml vial.