As of Monday, pubs and restaurants in England can start serving people food and drink outdoors, in what has been one of the most anticipated stages of ending lockdown.
However, environmental experts say reopening for outdoor dining only could cause a spike in air pollution from gas-burning patio heaters.
Gas-burning heaters emit nitrogen oxides (NOx) – a family of poisonous, highly reactive gases, warns Environmental Defense Fund (EDF).
NOx includes nitrogen dioxide (NO2), which can lead to health issues like inflaming airways while aggravating existing heart and lung diseases.
Using a single outdoor gas heater for five hours a day every day produces the same amount of nitrogen oxide (NOx) pollution as that produced by a typical gas-heated home in a year, EDF says.
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