Dust mites and the bedroom: what actually helps

The bedroom is usually the cleanest-looking room in the home and the one that matters most for anybody with a dust allergy. Those two things are true at the same time, and it is why the bedroom gets skipped.

Where they are

Dust mites are too small to see and they do not live on the bookshelf. They live where it is warm and there is skin to feed on: the mattress, the pillows, the duvet, the upholstered chair in the corner. The American Lung Association puts dust mite allergens in at least one bed in roughly four out of five homes in the United States, and notes that unlike pet allergens they do not stay in the air for long. Most exposure happens while sleeping, with your face on the pillow.

Humidity is the lever

The same source is direct about it: humidity is the most important factor in whether a home has high levels of dust mites, because they do not drink, they absorb moisture from the air. In a dry desert they cannot survive. In an August bedroom in Crown Point with the windows open, they can. Keeping the bedroom under fifty percent humidity, which usually means letting the air conditioning do its job, does more than any cleaning product.

The four habits

• Bedding washed in hot water every week and dried completely, including the pillowcases and the duvet cover
• Zippered covers on the mattress and the pillows, which put a barrier between the mites and the sleeper
• The bedroom kept below fifty percent humidity, checked with a gauge on the dresser
• The floor around the bed vacuumed, not swept, because sweeping lifts what is on the floor into the air

What does not help

A fresh-smelling spray on the mattress. Dusting the headboard and the nightstand and calling the room done. A new rug under the bed. None of it touches where the mites are. If someone in the home wakes up congested and is fine by lunchtime, the bed is the first place to look, and the four habits above are the whole answer.