security system
The ionization/photoelectric sensor smoke alarms above use standard batteries. However, they are inappropriate for those who live in a state or city that requires that battery operated smoke detectors be powered by sealed 10 year batteries. In that case, we suggest the First Alert SA3210 Est. $50. It's very similar to the First Alert SA320CN save for the power source a sealed 10 year lithium battery that complies with regulations in those areas that require them. It's not been professionally reviewed, but the handful of user reviews we spotted scattered on sites across the internet have largely been positive thus far. For example, though the totals are lumped in with the First Alert SA320CN at Amazon, all but 4 of the more than 30 that weigh in on the SA3210 specifically grant it either 4 stars or 5. Among combination smoke and carbon monoxide alarms, the First Alert SCO501CN 3ST Est. $50 looks like a top choice. Like the First Alert SA511CN2 3ST discussed in the section on photoelectric smoke alarms, the SCO501CN 3ST uses radio technology to set up a wireless network with other First Alert interconnectable alarms smoke, CO or combination without the complications that a hardwired interconnected alarm system would entail, though you might need to experiment a little with alarm location to make sure that each unit is within range of at least one other interconnected alarm. Reviews of the First Alert SCO501CN 3ST are mostly strong.