Calculation of Road Traffic Noise or CRTN (1998) published by the Department of Transport of UK. The CRTN provides the standard procedures for both predicting and measuring the noise levels for road traffic which are necessary to enable entitlement under the Noise Insulation Regulation. Measurements at site under CRTN are made using LA10,18h of a appropriate SLM of A type right after calibration. The method of calculation Road Traffic Control requires specific corrections and conversions to LA,eq to compare it to local or international standards. Further analysis and reporting considers proposals for noise reduction and control due to road traffic.