Hello and welcome to Health Care Magic
An occupational history of exposure to dust and chronic cough
suggests occupational lung disease
Presence of prominent vascular markings and heterogenous calcification on X-ray chest also suggests pneumoconioses.
Avoidance of exposure to dust associated with carpet work may be required. However, I don't know how fer that will be feasible.
Blood stained sputum should be investigated. There are many reasons for blood stained sputum. Tuberculosis and cancer are the main reasons for it.
can also lead to blood stained sputum but the incidence is low as compared to other causes.
You should consult a pulmonologist
for pulmonary function tests (PFTs).
PFTs will exactly charaterize the type of disease your father is suffering from.
Thanks and take care
Dr Shailja P Wahal