Generators and carbon monoxide

Carbon monoxide from generators and fuel-burning appliances is one of the biggest dangers in a long outage. Ready.gov's power outage advice (Ready.gov):

Run generators outdoors only, at least 20 feet from windows, doors and garages, and store fuel safely.
Install carbon monoxide alarms with battery backup on every level of the home and near sleeping areas.
Never use a gas stovetop, oven, grill or dryer to heat your home, and never leave a car running in a garage, even with the door open.
Learn the signs of carbon monoxide poisoning, which can feel like the flu.

Food in the fridge and freezer

Appliance	Keeps food cold for	If the door stays closed
Refrigerator	About 4 hours	Yes
Full freezer	About 48 hours	Yes
Half-full freezer	About 24 hours	Yes

Source: FoodSafety.gov. If the outage lasts more than 4 hours, throw out refrigerated meat, poultry, fish, eggs and milk. Thawed food can be refrozen if it still has ice crystals or is at 40°F (4°C) or below. Discard anything that smells, looks or feels off, and never taste food to check it. Keep an appliance thermometer in both.

Refrigerated medicine and medical devices

Make a plan with your doctor for storing medicine during an outage. Refrigerated medicine should be replaced if the power is out for a day or more, unless the label says otherwise; if it has been at room temperature, ask your doctor or pharmacist. Talk to your doctor about devices that need electricity and how you will power them (Ready.gov).

Light and appliances

Use flashlights or battery lanterns, not candles. Unplug appliances and electronics to avoid damage from surges when power returns, and follow any boil-water advisories.

Build it into your kit

The kit builder adds carbon monoxide alarms, flashlights, batteries and a radio to your checklist, and the reminders keep them working.