Laser safety

Laser can emit dangerous radiation. To protect against any injury international safety rules like IEC 60825 or ANSI Z136 were defined. The lasers are classified into different classes with the individual maximum permissible exposure limit (MPE) which is defined as intensity, power per square centimetre (W/cm²). To classify a laser one needs to know its intensity in order to compare it with the MPE values. For pulsed laser its energy is used instead of the power of continuous wave (cw) laser. Within the experiment P5.8.5.2 one pulsed and one cw laser is classified. For this purpose the intensity needs to be determined. To calculate this value the power and the beam diameter are measured. For the pulsed laser its repetition rate and the emitted energy is measured.