Siretta nagios based temperature humidity and light sensor with email alerts siretta em01b vlt the nagios sensor from siretta can be used to monitor temperature humidity light and door access remotely with the option to add the es hub and have up to six flood sensors or five and an lcd display the em01b stn is the entry level version of this very flexible monitor easy to use and set up the em01b offers exceptional value in monitoring parameters via a lan connection with its own web ad