When the block goes dark, people make worse decisions because they cannot see. Headlamps leave both hands free. Spare batteries, stored with the lamps, matter more than a decorative lantern that eats rare cells.

Hands free is the point. You will carry water, steady a child, and open a panel with the same two hands that would otherwise be holding a flashlight in your teeth. One lamp per person means nobody has to lend their eyes away.

Match the batteries to the lamp and buy the cell you can still find, not a specialty size that lives in one store. Store them in the device or in the same bag, cool and dry. A lamp without cells is a paperweight you notice at the worst minute.

Candles start fires in houses that are suddenly full of improvised cooking. If you use flame, use it on a stable surface, away from bedding, and blow it out before sleep. Chemical light sticks are the boring, correct backup.

Flame plus unfamiliar cooking is how a blackout becomes a fire call that may not be answered quickly. If the stove is electric and dead, do not invent a burner on a couch. A light stick does not tip over. It also does not pretend to heat the room, which is a virtue when people are tired and improvising.

Mark the stairs, the water, and the radio with something you can find by touch. You will be tired. Design for tired.

A piece of tape, a knot, a shelf that is always the same shelf. Put the lamp where the hand already goes — by the bed, by the door — and practice finding it once with the room lights off, on an ordinary evening. The first night is when the habit is not built yet.