The results are presented of an investigation comparing the performance of commercially available liquid scintillation spectrometers claiming 'low-level' radioisotope detection abilities. Determination of ¹⁴C at naturally occurring concentrations was carried out in both old and new technology liquid scintillation counters using a ¹⁴C labelled benzene sample with butyl-PBD as scintillant. The signal to noise ratio and the ¹⁴C detection efficiency were evaluated. The results show a wide range of merit for radiocarbon dating of so called 'low-lever instruments.