BiPAP use in ILD:  Uncommon.  ILD causes stiff and noncompliant lung due to fibrosis.  BiPAP offered less effective for hypoxemia in ILD.  BiPAP is more helpful in hypercapnic respiratory failure which is uncommon in pure ILD. 

Risk is barotrauma, discomfort and poor tolerance, delaying intubation.

ILD patient with overlapping condition like CHF COPD, BiPAP might be used to bridging to intubation.

Bottom line:  BiPAP not absolutely contraindicated but use selectively.  In pure ILD with severe hypoxemic respiratory failure, high floor nasal cannula or mechanical ventilation is usually preferred over BiPAP.