Comparison of two identical continuous flow nucleus counters

Abstract A review of the literature on the comparison of identical nucleus counters showed that only Pollak counters exhibit a high degree of agreement. In view of the difficulties encountered by early investigators in obtaining good agreement, we subjected two Sinclair continuous flow nucleus counters to similar tests using room aerosol. Our results indicate that under normal operating conditions the continuous flow counters can agree to within 10% of concentration measurements. We also inferred from our measurements that these counters have good reproducibility.