IP means International Protection class of an electrical machine. It classifies and rates the degree of protection provided against intrusion. It is published by the International Electrotechnical Commission (IEC). The standard aims to provide users more detailed information than vague marketing terms such as waterproof. The two digits indicate conformity with the conditions. Where there is no protection rating with regard to one of the criteria, the digit is replaced with the letter X. Most blowers are: IP55 meaning dust and waterjet protected.