A fluid level sensor assembly for monitoring a fluid level in a fluid collection canister of a medical waste fluid collection system. The fluid level sensor assembly includes a fluid level sensor configured for monitoring the fluid level in the fluid collection canister and a fluid level sensor cover configured for preventing direct contact between the fluid level sensor and a fluid in the fluid collection canister. The fluid level sensor cover includes a polymeric cap and polymeric sheath extending from the cap. The elongate tubular sheath surrounds an elongate probe of the sensor with the cap positioned at a base of a sensor body of the sensor to prevent direct fluid contact with the elongate sensor probe and the sensor body.