A worldwide standard has been established by the International Electrotechnical Commission (IEC) for comparing the ability of electronic devices to withstand exposure to dust particles and water.
The ratings established by the IEC for resistance to particulates and water are called “Ingress Protection” or “IP” ratings, and are defined by IEC 60529, Degrees of protection provided by enclosures (“IP” Code), for all IP Codes. A full rating contains two digits, each of which can take avalue of 1 through 6. The first measures the ability of the device to resist the ingress of foreign objects, or dust. The second measures the ability to resist the ingress of moisture. The first digit can have a value from 1 to 6, the second a value of 1 to 8. The higher the number, the better the protection.
The ZOLL AED Plus® has a rating of IP55. This means it is dust protected and protected against water jets.