Here in Southampton for a period of 4 hours, 7-11 pm, the AQI was at 312 = The HAZARDOUS level being an AQI of 300-500, which is the highest range. Yes, bonfire night here was compared to the pollution levels in Delhi, India.
Yesterday morning (from 8 am) also saw a blanket of wood smoke across the estate, with a population 15,000 souls.