Measurement apparatus

A measurement apparatus that measures a parameter of a sheet-like subject, the measurement apparatus comprising:

• a pair of sensor heads that are separated from each other, travel horizontally while being opposed to each other, and scan a subject positioned between the sensor heads;
• a support that supports the pair of sensor heads such that the sensor heads are movable in a horizontal direction;
• an electric unit that is mounted on the support and is changeable in position to either a first position on one side along a travel direction in which the sensor heads travel or a second position on the other side along the travel direction, and that controls measurement of the parameter using the sensor heads;
• an opposed unit that is mounted in the second position when the electric unit is mounted in the first position and that is mounted in the first position when the electric unit is mounted in the second position;
• a first operation unit that is mounted on the opposed unit and that stops supplying power to the sensor heads;
• and
• a second operation unit that is mounted on the opposed unit and that switches between supplying power to the sensor heads and stopping the supply according to an operation on an insertable key.