In Switzerland, as in many other countries, there are precise regulations about what you must have with you in the vehicle in case of an emergency or a breakdown.
In Switzerland only the breakdown triangle is mandatory.
On roads where speeds of up to 50 km/h are permitted (in urban areas), you must place it 50 meters behind your car. On roads where you can drive faster than 50 km/h (out of town) you have to place it 100 meters behind your car. Please be on the right side of the road and clearly visible. If your car is directly behind a curve or crest, place the breakdown triangle in front of it. This means approaching vehicle drivers can see it early.
How far is 50 or 100 meters? Take 60 or 120 big steps from your vehicle. This gives you roughly the distance you need.
Why this distance? The approaching vehicle drivers need this distance in order to be able to bring their vehicle to a safe stop behind you. You remember? Stopping distance = reaction distance + braking distance?
Tip: If you need to set up your breakdown triangle, place the empty cover of the breakdown triangle on the driver's seat. Bet you won't forget your puncture triangle on the side of the road?
Even if it is not mandatory in Switzerland, it is still advisable to have high-visibility vests and a first aid kit with you. High-visibility vests increase your visibility enormously, even in good weather and daylight. They offer you and all other road users more safety through better visibility. Plus, you never know whether a passenger might need a plaster or a bandage. That's why it's recommended to have a first aid kit with you. Don't forget to put a reminder in your phone calendar, because even a first aid kit has an expiration date.
In the driving school car, the breakdown triangle is located in the trunk under the cover. High-visibility vests (5 pieces, one for each seat) and the first aid kit are in the black box in the trunk.
You can put out a vehicle fire (only at the very beginning) with a fire extinguisher or a fire blanket. But please don't put yourself in danger.
Other countries have different regulations. Even if you just drive your car quickly across the border into Germany to pick up a package or go shopping, as soon as you have crossed the border, you must have the mandatory equipment required in the respective country with you.
On the TCS website you will find a good overview of what is required in the surrounding countries. (only on german)