Describes the determination of low radiocarbon activity by ₁₄CO₂ absorption in a gel type liquid scintillator (Instagel). The samples of ₁₄CO₂ were introduced into Instagel using Carbo-sorb as an absorption agent. The reproducibility of the method, determined by the root mean square deviation of 14 identical samples was 1. 25%. The described method is very simple and rapid. The NBS oxalic acid standard is measured by a standard deviation of 2.8%. Methods of collection of atmospheric and hydrological samples are described. -- AATA