Apparatus and methods for monitoring optical fiber system integrity

A monitor for monitoring an optical fiber line coupled to a tubular string, the monitor comprising:

• a housing configured for use in a subsea environment, the housing containing:
• a light source configured to send an input optical signal into the optical fiber line;
• an optical sensor configured to detect an output optical signal from the optical fiber line;
• and
• a controller coupled to the light source and to the optical sensor, wherein the controller operates to control the light source to send the input optical signal and to control the optical sensor to detect the output optical signal, wherein the controller comprises instructions that cause a plurality of operations to be conducted when the instructions are executed, the plurality of operations comprising:
• receiving a first data signal from the optical sensor based on the output optical signal;
• determining, from the first data signal, a condition of the optical fiber line;
• generating a synopsis of the condition, wherein the synopsis comprises a classification of integrity of the optical fiber line as being one of at least three categories based on a comparison of an attenuation coefficient or a quantification of signal loss against one or more threshold values;
• and
• sending a second data signal comprising the synopsis;
• and
• a power source.