Japan’s National Consumer Products Office on Sunday ordered the recall of 486,000 KiriClear M8 air purifiers after tests found that their smoke sensors can switch the machines into low-flow mode during heavy pollution. The announcement came as smoke from fires across northern Honshu drove fine-particle readings above health guidance in parts of Tokyo.
Authorities say 57,000 hectares have burned across six prefectures since mid-August, with 19 fires still active. Smoke advisories now cover 8.7 million people in Tokyo, Sendai and Niigata, while forecasters expect another plume to reach the capital late Sunday.
Recall hits homes and schools
The recalled units, made by fictional household-appliance manufacturer Hibana Air Works, were sold between February 2024 and August this year. In laboratory tests, the sensor misread dense smoke as a reason to reduce fan speed; the company says owners can request a replacement, but deliveries may take up to 10 days.
The product notice does not report confirmed injuries. Yet Julija Kolenc, an aerosol scientist at the East Japan Climate Observatory, said the timing was dangerous for households relying on the machines. “A purifier that quietly slows down when smoke thickens can give people confidence while removing less pollution,” she said.
A purifier that quietly slows down when smoke thickens can give people confidence while removing less pollution.
Julija Kolenc, aerosol scientist
The government says outdoor readings remain below emergency thresholds in most monitored districts and has urged residents to follow local guidance. Wera Marquardt, a senior official at the National Consumer Products Office, said the recall was precautionary and that “there is no evidence the machines have caused a medical emergency”.
Forecasts sharpen the dispute
Augustina Ndukwu, a fire-and-weather modeller at the Pacific Smoke Observatory, estimates the burned area could reach 110,000 hectares by 4 October if rain misses the central mountain belt and dry winds persist. Her team’s projections show smoke levels in some Tokyo wards briefly exceeding 75 micrograms of fine particles per cubic metre, more than five times the World Health Organization’s 24-hour guideline.
Japan’s forestry agency says the fires remain geographically separated and that current wind patterns should prevent a single continuous front. The observatory disputes the reassurance: Ndukwu said smoke from separate fires can merge over cities, and that a shift in wind direction could keep pollution trapped over the Kanto plain for several days.
Tokyo officials are weighing temporary clean-air rooms in libraries and public buildings, limits on outdoor school activities and free replacement filters for low-income households. The city has not announced a general mask distribution, saying its monitoring network will guide decisions hour by hour.
The fires have also brought wildlife closer to settlements. In Fukushima and Miyagi, forestry staff have logged 31 bear sightings near villages since 1 September, a rise they associate with animals moving away from scorched slopes; residents have been asked to report sightings and avoid forest roads.
Oskar Nowak, Hibana Air Works’ Japan sales director, said the company had begun contacting registered buyers and would publish a list of affected serial numbers. But with replacement units delayed and the smoke season not expected to ease before October, Kolenc said households should not assume a recalled purifier is protecting them until it has been checked.
