Personnel activity at a construction site is tracked using electronic circuitry included in hard hats worn by personnel at the site. According to one embodiment, activity at a construction site is monitored by processing personal information directly or indirectly received from electronic circuitry formed as part of one or more hard hats worn by personnel located at the construction site. The personal information is uniquely associated with individual ones of the personnel. One or more messages are generated based on the personal information received from the electronic circuitry and personnel location. For example, the messages may warn particular personnel that they have entered an unauthorized area at the construction site. Optionally, personnel activity may be periodically monitored and reported.