Valve Diameter of orifiice Surface marking Ausculatory area Pulmonary valve 2.5 cm Upper border of the sterna end of left 3rd costal cailage Left 2nd intercostals space near the sternum Aoic valve 2.5 cm Lower border of the sternal end of left 3rd costal cailage RIght 2nd intercostals space near the sternum Mitral valve 3 cm Left half of the sternum near the left 4th costal cailage Cardiac apex Tricuspid valve 4 cm Right half of the sternum opposite the 4th & 5th intercostals space Lower end of sternum on the left side