The B15 is IP67 certified, which means both protected from dust and waterproof up to 3.3 feet for 30 minutes and can be dropped from about six feet and live to tell the tale -- you, however, may not.
They are certified to MIL-STD 810G for extremes in temperature, vibration, shock and four-foot drops and have an IP65 rating for ingress protection, which means they are fully protected against dust and can withstand low pressure jets of water from all directions.