Cleaning crews finished work on Sol’s ventilation shafts at about 14:00 on Saturday 17 October. Technicians from Metro de Madrid’s Prevention Area supervised the checks. The station closed around midday on 16 October, after a housing-affordability protest camp had occupied Puerta del Sol for almost three weeks. Metro de Madrid said organic waste, including urine and faeces, had accumulated in the ventilation system.
Specialist equipment needed access to the ventilation shafts through exterior grilles in the square, the regional government said. The camp occupied those grilles, blocking the cleaning work. Measurements in the ventilation system recorded ammonia concentrations reaching 80% of the occupational exposure limit. After cleaning, workers ventilated the station and collected samples for laboratory analysis.
The results confirmed that health and safety conditions were satisfactory. Sol reopened at 22:00 on Saturday 17 October. Metro de Madrid said documented analysis confirmed that the necessary conditions had been restored. The urgent closure was covered in earlier reporting. It affected the Metro section of the Sol complex, while Cercanías Renfe continued operating its part of the station.
Line 1 has resumed stopping at Sol, along with Lines 2 and 3.
Madrid regional councillor Jorge Rodrigo, whose portfolio covers transport, housing and infrastructure, thanked Metro staff for their work and commitment to passenger safety. The closure came amid a dispute over the protest camp: participants said the square was cleaned daily, while regional president Isabel Díaz Ayuso linked the sanitary concerns to the camp.
