The oldest and simplest way to get a general overview of the internal condition of a straight section of inaccessible sewer is to directly look inside of it with the help of a mirror and an additional light source. The mirror, held at a 45° at the opening of the pipe, allows for inspection to take place without the need for direct entry into the manhole by personnel. Additional lighting shun into the pipe section, either at the next manhole or directly into the mirror at inspection point, is necessary to determine the condition of the line.