Historically, scientists who perform low-level measurements of 14C for age dating, and 3H2O for environmental contamination, have purchased or constructed highly specialized instruments to quantitate low-level radionuclides using a general-purpose liquid-scintillation analyzer (LSA). The LSA uses special time-resolved 3-D spectrum analysis (TR-LSC) to reduce background without substantially affecting sample counting efficiency. This technique, in combination with a special slow fluor scintillating plastic, further reduces the minimal detectable limit for the TR-LSC liquid scintillation counter.

In closing this workshop, I must thank all of the delegates for making this meeting so very enjoyable for ourselves, the organisers. So much so that we will give serious thought to inviting you back to Scotland very soon. The meeting has, in our view, been eminently successful in the scientific sense. I believe that we have made uniquely important and fundamental observations and plans for the future of 14C dating. I would like to summarise quickly my personal view of the main findings of the workshop. I would start this by recalling the eight questions posed in my opening address. The questions and my impression of the workshop's answers are as follows:

The purpose of this Quality Assurance (QA) protocol is to summarize guidelines that have been accepted by directors of many radiocarbon dating laboratories throughout the world, and by the International Atomic Energy Agency (IAEA). Some laboratories have followed similar procedures successfully for years. Laboratories that carefully adhere to this protocol will produce consistently reliable data that will be comparable in accuracy to all other laboratories following this or any other equally rigorous quality assurance program. This statement does not, however, pertain to samples with 14C activities highly sensitive to method or degree of pretreatment, as pretreatment techniques vary among laboratories.