Smoke & Carbon Monoxide Alarms

There are ionization, photoelectric, and dual-sensor smoke alarms; ionization detects fast-flaming fires, photoelectric is better for smoldering fires, and dual-sensor combines both. Carbon monoxide (CO) alarms use electrochemical sensors. Choose based on the risks in your home (kitchens and garages favor photoelectric or dual for smoke; any fuel-burning appliances require CO detection) and local code requirements

Battery-powered alarms are easy to install and work during outages; hardwired alarms (often with battery backup) are integrated into a house electrical system and can be interconnected; plug-in alarms are simple for rentals or temporary use. Select hardwired with interconnect for permanent installs where building code requires it, otherwise sealed long-life battery or plug-in models are common choices

Install a smoke alarm inside each bedroom, outside sleeping areas, and on every level including the basement; install a CO alarm outside sleeping areas and near potential CO sources. Follow local building codes and manufacturer placement guidelines (avoid installing near windows, vents, or very humid areas)

Key features include sensor type (photoelectric vs ionization), interconnectivity (wired or wireless) so all alarms sound together, sealed long-life batteries or user-replaceable batteries, clear audible or voice alerts, and smart connectivity for remote notifications. Choose features that match your safety needs, household layout, and preference for remote monitoring

Most smoke and CO alarms have a usable life of 5–10 years; manufacturers recommend replacing the unit at the end of its life. Test alarms monthly, replace batteries yearly or when the low-battery chirp sounds (or choose sealed long-life battery units), and vacuum around the housing occasionally to remove dust

Photoelectric alarms are generally less prone to nuisance alarms from cooking or steam than ionization types, making them a better choice for areas near kitchens or bathrooms. However, avoid placing any alarm directly within 3–5 feet of cooking appliances or in high-humidity zones to minimize false alerts

Look for alarms certified by recognized testing labs (for example, UL, ETL, or equivalent regional standards) and that comply with local building codes. CO alarms should meet CO sensor performance standards and smoke alarms should meet applicable smoke detection standards for reliable performance