Fiber optic sensor coil including a restraining ring and method of forming

A fiber optic sensor coil comprising:

• a plurality of turns of a first segment of optical fiber wound about an axis in a clockwise direction and a plurality of turns of a second segment of optical fiber wound about the axis in the counterclockwise direction;
• the turns of the first segment and of the second segment together forming a plurality of layers of turns of optical fiber;
• and
• a restraining ring covering an outermost layer of the plurality of layers of turns of optical fiber, the restraining ring including a plurality of openings formed therein and providing a compressive force to the plurality of turns of the optical fiber, the plurality of openings being disposed along a plane substantially parallel to the axis and providing a fluid egress from the plurality of layers to the ambient encompassing the coil.