It is warm and the heat will continue over the coming days. For many people, this means enjoying the beach or garden. For others, heat can be less enjoyable. People who are not able to take good care of themselves need extra attention on hot days to limit heat inconvenience and prevent health problems. That is why the National Heatwave Plan is effective as of Monday, 18 July 2022. The heat in large part of Europe can also cause smog. People who are sensitive to smog can suffer from it. That is why, in addition to the heatwave plan,  a smog warning applies.

The heatwave plan and the smog warning apply to the entire country. RIVM decided on this after consulting the Royal Meteorological Institute (KNMI) about the predicted persistent heat. According to KNMI, the warm weather could persist through Wednesday.

Vulnerable groups

Warm weather can cause people unable to take good care of themselves to experience discomfort (such as fatigue, headaches and concentration problems) and more serious health problems (such as dehydration and heat stroke). Older people are the most vulnerable group because they have poorer body temperature control and are less likely to feel thirsty. Other groups can also experience discomfort or health problems if no measures are taken. For example, people with chronic illnesses, people in social isolation, the homeless, overweight people and (very) young children. Everyone is affected by extreme heat and high ozone concentrations (summer smog) in summer. Still, summer smog mainly affects vulnerable groups, such as the elderly, children, people with respiratory diseases and people who exercise outdoors. 

How to prevent heat inconvenience and health problems 

It is good to think about whether there are people around you who are vulnerable and pay extra attention to them. The most important tips for everyone that will help prevent discomfort and health problems caused by the heat and smog are:

  • Drinking enough (water); 
  • Keeping the house cool (use blinds, fans or air conditioning);
  • Limiting physical activity in the afternoon and early evening.

It is also wise to prevent sunburn. It is important to use sunscreen. 

National Heatwave Plan

The National Heatwave Plan is an action plan aimed at alerting organisations, professionals and volunteers in good time to the forecast of persistently warm weather and the need to take measures to protect vulnerable groups. This allows them to take appropriate measures to reduce and (where possible) prevent discomfort and health problems in vulnerable groups such as the elderly. Even people in good health can suffer from overheating or heat exhaustion if it is hot for a long time and the temperature is very high. 

Ozone smog

Smog due to ozone occurs when air pollution builds up on sunny days. RIVM advises people who are sensitive to smog to stay indoors and limit heavy physical activity. In Europe, an information and alarm threshold has been set. The EU European Union (European Union) has defined an Information threshold of 180 micrograms of ozone per cubic metre of air. If this value is exceeded, or there is risk of it being exceeded, people who are sensitive to smog may experience symptoms. RIVM will then issue a smog warning. According to the Dutch Air Quality Index, this results in poor air quality. The EU alert threshold is 240 micrograms of ozone per cubic metre of air. The air quality is then "very bad", according to the Dutch Air Quality Index. When this value is exceeded, anyone can get complaints. In that case, RIVM turns the smog warning into a smog alert.