Which type of face mask is best suited for nhl cancer patients? for eg. "curad biomask antiviral isolation mask"

This is fine: But it may be more costly than the ordinary masks. Curad mask is specifically meant to keep the flu virus away. Since influenza season is now almost over, you do not need to spend much money as your risk would be more from bacteria. But do not get too hung upon masks, they are not routinely advised to be used on patients receiving chemotherapy as nearly all infections arise from your own germs!