Tech to help you monitor your indoor air, upgrade an old alarm system, and control your shades.

We spend about 90 percent of our time indoors. Today’s technology can tell us the quality of our indoor air so we can improve it.

The Airthings Wave Plus monitor ($300 online) sends realtime air quality data to your phone with six sensors that monitor:

■ TEMPERATURE. The ability to check your home’s temperature while you’re away—especially if you relocate in the winter— can prevent a plumbing pipe catastrophe.

■ HUMIDITY. Keeping your home at an optimum humidity level wards off mold from too much moisture. It also reduces your household’s susceptibility to flu, colds and allergies from air that’s too dry.

■ AIR PRESSURE. Knowing whether air is escaping or infiltrating, and at what rate, is important for energy efficiency.

■ RADON. Radon is a known cause of cancer, and unsafe levels must be mitigated. Also, many states require full disclosure of unsafe radon levels with the sale of a house.

■ CARBON MONOXIDE. Carbon monoxide (CO) is known as the silent killer. It’s vital to know that CO levels are in check.

■ VOLATILE ORGANIC COMPOUNDS (VOCs). Common cleaners, paints, building materials, carpeting and other products emit VOCs that can linger in your home for a long time. VOCs can be mildly irritating or cause cancer or damage the central nervous system.

I’ve had the Wave Plus set up in my basement laundry/utilities area for two months. My sensor averages have been in the green, but I did notice a spike in CO when the dryer was running. After I retaped some duct seams, those CO spikes lessened noticeably. If an air monitor motivates the ounce of prevention needed to ensure a safe and healthy house, then it’s a smart thing worth having.