Other preventive measures against the formation of aerosols and against their negative effects include:

• Use of invert nozzles in large sewer cross-sections,

• Reduction of the pump pressure approximately 10 m before reaching the starting manhole,

• Use of breathing- and eye protection

• Covering the manhole opening with a steel or plastic cover equipped with openings for the HP flushing hose and the suction tube.

[ATV1997]