No need to rebuild the wheel, most data centers have various monitoring capabilities ranging from WebServer enabled monitoring systems (personally I like the units from ITWatchDogs), SNMP trapping to hand written scripting. Just borrow that functionality for your lab equipment.
Here's what I do to monitor temp, security, water leaks, fire etc:
Purchase a sensor unit that supports SNMP trapping or is able to push email alerts (WeatherGoose II ITWatchDogs was about the cheapest I could find for DC rack monitoring needs I had that supported lots of external devices, dialers etc). Since it supports various external sensors, you can make your own and tie it into the monitoring system (temp, humidity etc are built in, but smoke alarms etc are extra add-ons that either you buy or you can make as long as it's the right voltage).
If using SNMP, have a monitoring server that can react any number of given ways, mine sends screen shots of the room from the security camera as well as and various alerts for too high temp, water leaks etc. If it's fire, it CC's our emergency fire system. I also use other things like "Site Uptime" monitors and such from 3rd parties on the email front, but that's more targeted at mail servers.
For email alerts, I have a couple rules in Exchange (on the server level) to distribute it accordingly.
I do use Tasker heavily to automate my phone, but really I don't rely on it as being mission critical as you never know when you'll be out of reception. Instead I try to use the servers to handle responses to the rest of my team and use Tasker to control when and when not to wake me up in the middle of the night.