In one aspect, the present invention provides a hermetically sealed fiber sensing cable comprising: a core fiber comprising at least one Bragg grating region, an outer surface and a length; a fiber cladding in contact with the core fiber along the entire length of the core fiber, the fiber cladding having an outer surface and a length; a carbon layer disposed upon the outer surface of the fiber cladding along the entire length of the fiber cladding, the carbon layer comprising diamond-like carbon; a hydrogen ion absorption layer in contact with the carbon layer, the hydrogen ion absorption layer being disposed on the outer surface of the carbon layer; and an outer sleeve. Also provided in another aspect of the present invention, is a component for a hermetically sealed fiber sensing cable.