With temperatures upwards of 40C expected in some parts of Germany this week, the heatwave is in full swing.
Forecasters say the mercury is rising, particularly in western regions, with the hottest day expected to be Thursday.
READ ALSO: 'Heatwave could go down in history': Germany faces temperatures up to 41C
And due to the fact that many public places don't have air conditioning, it could become unbearable.
If this happens, German schools and workplaces can declare hitzefrei (literally, heat free), which means pupils or employees can take the rest of the day off due to excessive heat.
But there are rules to follow for this to happen, and it usually comes down to state regulations for schools and the employer’s decision for workplaces.
Here's what you need to know.
What applies to employees?
Firstly, hitzefrei is no new concept. A version of it dates back to 1892 when a ministerial decree was made in Prussia, Germany daily FAZ recently reported.
Nowadays, the employer is in principle free to decide when it is too hot as there is no legal framework for employers to follow when they feel they need to switch off their computer and go swim in a lake.
However, labour law provides for certain recommendations that employers should adhere to in the event of high temperatures. Workplace regulations stipulate that room temperatures should not exceed 26C in order to protect health.
READ ALSO: Ditching AC for 'hitzefrei': Taking on the German summer as a Californian
If the room temperature exceeds 30C, the employer is obliged to take measures to protect employees. This applies not only to offices, but also to shops, warehouses, workshops or wherever the employee's place of work is.
Furthermore, technical regulations for workplaces stipulate: "If the air temperature in the room exceeds +35C, the room is not suitable as a work area without technical measures (eg industrial air showers, water sprays), organizational measures (eg time allowed for people to cool down) or personal protective equipment (eg heat-protective clothing), as is the case when working in hot environments."
In other words: bosses must design their workplaces in such a way that health hazards are avoided. Air conditioning systems, fans and blinds can make rooms more climate-friendly.
Alternatively, the employer can provide a cooler place to work. People who work outdoors should stay in the shade and drink enough water.
In June's sweltering weather, some German outdoor workers were advised to start much earlier in the day. For example in North-Rhine Westphalia, road workers who start at 6.45am could begin at 4.45am. It means they finished earlier and avoided the worst of the sun.
Workplaces such as canteens and first aid rooms in workplaces must have temperatures that are beneficial to health (and not too hot).
If employees have concerns they should talk to their bosses to see what can be done to bring the temperature of the room down.
What about schools?
There has been no nationwide regulation for schools on when pupils should be sent home due to the heat since 1999, FAZ reports. Instead, each federal state decides for itself. In Baden-Württemberg, North Rhine-Westphalia, Rhineland-Palatinate, Berlin and Hesse, the heads of each individual school have to make the decision.
Some schools in North Rhine-Westphalia chose to shorten the days for pupils due to the recent extreme heat.
As school buildings differ in construction and location, temperatures can vary. Hitzefrei is valid if lessons are impaired by high temperatures in the classrooms. Usually, if a room temperature reaches 25C to 27C or higher, schools take action.
If temperatures are more than 25C outside in the shade by 10am, the school management can also think about sending kids home. Sometimes instead of a day off, teachers choose to relocate lessons to cooler places or take the students on short excursions.
Room temperatures of less than 25C are usually not considered to be excessive. Hitzefrei can be problematic for families with younger children because it requires agreement with the parents, who may have to take time off work to pick up their offspring.
READ ALSO: What working parents in Germany need to know if their child is sick
It's a good day to go a lake, like this one in Müggelsee, eastern Berlin. Photo: DPA
Pupils at secondary school on the other hand, usually do not get a full hitzefrei day unless, for example, there is a risk of circulatory problems in their classrooms.
Teachers are advised that class tests (for all levels) should be avoided on days when the heat is too much.
So if you overhear this: Ich muss heute Nachmittag nicht in die Schule. Wir haben hitzefrei (I don't have to go to school this afternoon. We have heat free time) then perhaps there's a chance your boss might let you finish up early too - but don't count on it.
Heatwave - (die) Hitzewelle
Air conditioning - (die) Klimaanlage
Unbearable - unerträglich
To get a heat free day - hitzefrei bekommen
Labour law - (das) Arbeitsrecht