Housing corporation Staedion is installing mobile air cleaners in 39 apartments on Lisztstraat to bring down formaldehyde levels found after the facade was insulated with UF foam.
Readings in August found concentrations far above the limit in 11 of the flats, and the corporation says the foam releases the gas as it hardens.
The gas can irritate the eyes, nose and throat and cause nausea or headaches, and residents report watering eyes and tightness in the chest.
Filters and testing
The cleaners contain active carbon filters designed to trap formaldehyde, and Staedion is fitting them in all 39 apartments and paying the extra electricity costs.
New measurements in four to six weeks should show whether the filters work, and a fresh investigation is starting after something went wrong with earlier samples taken from the wall.
The mechanical ventilation has been reset to blow fresh air through the building, and extra vents have been fitted in doors to the galleries and entrance.
Seven residents have moved into temporary flats, where they can stay for three to six months.
Staedion says the foam cannot simply be removed, because it binds into every gap and soaks into the material in the cavity.
