The nasal cannula manifold 10 comprises: an inlet 40a,40b configurable to receive pure oxygen or oxygen-enriched therapeutic gas from a gas supply line and at least one outlet 50a,50b insertable into a nasal opening to deliver said oxygen or oxygen-enriched therapeutic gas. At least a portion of the outlet 70a,70b comprises a polymeric material which is fire resistant in the presence of the oxygen or oxygen-enriched therapeutic gas. Aspects and embodiments recognise that it may be possible to provide a comfortable, yet fire resistant, nasal cannula by providing at least an inner portion 70a,70b of the nasal cannula manifold which is fire resistant in an oxygen enriched environment, yet retaining a soft pliable feel to at least an outer 50a,50bs, client interface, region of a cannula outlet, such that patient comfort is maintained.