Normal values for lung capacity, under normal circumstances, are about 3000-4000 ml for men. while for women it is about 2000-3000 ml. This shows that a lung capacity of 8000ml is often not normal. Usually in lung surgery or pulmonary fibrosis, can cause a reduction in lung capacity. However, when it exceeds the normal value by this much, up to 8000 ml, it is very likely that there is an error in the way the test was performed, for example, the patient did not hold his/her breath well or the instrument was not calibrated. Overall, 8000 ml is definitely not normal, and it is important to find out where the error occurred, both from the patient’s point of view and from the instrument’s point of view.