How often should I apply sunscreen? Do I need to carry sunscreen with me?

When summer comes, sunscreen is a must-have item when going out. I heard that sunscreen is only effective for 4 hours. Is this true? How often should you reapply sunscreen? Do you need to carry sunscreen with you?

Sunscreen should generally be applied every 3-4 hours, depending on different sun protection needs. For office sun protection, use SP15PA+ sunscreen, and reapply every 4-5 hours; for outdoor sports sun protection, use SPF25-30PA+ sunscreen, and reapply every 3-4 hours; for swimming sun protection, use SPF30PA+++ or above, and reapply every 1-2 hours.

Sunscreen is a restricted item. Sunscreen or sunscreen spray exceeding 100ml cannot be repacked on site and cannot be brought on board the aircraft.

1. Regulations on international and regional flights

1. Liquid items should be placed in a single container with a volume not exceeding 100ml and carried with you;

2. Containers for liquid items should be placed in resealable transparent plastic bags with a maximum container size of no more than 1L;

3. Each passenger is only allowed to carry one transparent plastic bag at a time;

4. The excess liquids should be checked in as baggage.

2. Domestic flights

Liquid items are not allowed to be carried on board (except for cosmetics, toothpaste and shaving cream for personal use during air travel).

The film-forming time of general sunscreen is about 3-10 minutes, and the longest time is no more than 10 minutes. After applying sunscreen, sprinkle water on the skin, and you can see water droplets forming on the skin, which means that the film has been formed. In order to ensure the film-forming effect, sunscreen should be applied half an hour before going out.

Sunscreen actually needs to be applied every day, because the biggest function of sunscreen is to protect the skin from damage caused by ultraviolet rays, and ultraviolet rays are not only present in summer or when the sun is out. In fact, in winter or on cloudy days, there are still ultraviolet rays, and ultraviolet rays can cause great damage to the skin.