A nurse is planning discharge teaching for a client with persistent asthma who lives in a household with smokers. The client reports frequent nighttime symptoms and exacerbations. Which intervention should the nurse include in the client's asthma management plan to reduce the client's environmental triggers?

For a client with persistent asthma who lives with smokers and experiences frequent nighttime symptoms, encouraging the use of air purifiers in the bedroom and living areas is the most appropriate and evidence-based environmental control strategy. HEPA air purifiers remove airborne allergens, smoke particles, and other triggers from indoor air, directly addressing secondhand smoke exposure and other particulate matter that the client cannot fully avoid when living with smokers. Recommending hard flooring to reduce dust mites is a reasonable long-term measure but is less immediately impactful than addressing the smoke exposure, and it may not be feasible financially or practically. Advising the client to keep windows open to improve ventilation is contraindicated because open windows increase exposure to outdoor allergens such as pollen and pollution, which can worsen asthma; this option is incorrect and potentially harmful. Teaching the client to avoid outdoor exercise during peak pollen hours addresses an outdoor trigger but does not address the primary identified trigger of living with smokers indoors. The keyed answer suggesting open windows contradicts established asthma management guidelines, and air purifiers represent the correct, evidence-based choice for reducing indoor environmental triggers, particularly secondhand smoke.