Rigol MSO1000Z series User Manual page 13

RIGOL
Pollution degree 2: Normally only dry, non-conductive pollution occurs. Occasionally
a temporary conductivity caused by condensation may occur. For example, general
indoor environment.
Pollution degree 3: Conductive pollution occurs, or dry, non-conductive pollution
occurs which becomes conductive due to condensation which is expected. For
example, sheltered outdoor environment.
Pollution degree 4: Pollution that generates persistent conductivity through
conductive dust, rain, or snow. For example, outdoor locations.
Safety Class
Class 1 – Grounded Product
MSO1000Z/DS1000Z User's Guide XI