Calculating a noise contour or the noise level at a receiver point is usually the starting point of a noise study.  you will then need to appraise the situation, make changes and extract conclusions.

Noise Map has powerful Results Processing capability to assist with this.   Typical requirements are;

• Add a fixed offset
• Add a noise floor
• Subtract two sets of results to obtain a change of level
• Add two or more results to get a cumulative effect
• Compare results with a criterion to show areas in excess

NoiseMap expressions can use a range of operators, inlcuding the usual arithmetic, logarithmic and and conditional tests allowing a wide range of results processing.  The processed results can be shown on-screen and also exported.