The present invention relates to a hard hat, comprising: a rigid outer shell, a vibration transducer secured to the exterior of the rigid outer shell, the vibration transducer operative to vibrate the rigid outer shell when active; and a control system coupled to the hard hat, the control system further operably coupled to the vibration transducer such that the control system controls vibration of the vibration transducer. The control system converts received audio communication into a signal sent to the vibration transducer such that activation of the vibration transducer results in vibration of the rigid outer shell, with the rigid outer shell thereby acting as a harmonic resonance acoustic chamber replicating the received audio communication. A kit for converting a hard hat and a method of communication are also disclosed.