Apply sunscreen with 2 fingers or 2 knuckles. What is the correct amount of sunscreen? Let’s find the answer. How to apply sunscreen properly. Protect against UV rays for beautiful, clear skin that doesn’t darken or damage.
Apply two fingers of sunscreen VS 2 fingers, which one is correct?
Applying too little sunscreen will not provide the protection it needs from the sun and UV rays. The SPF value stated on sunscreen is derived from skin testing. Applying 2 milligrams of sunscreen per square centimeter of skin area (2mg/cm2) is the standard worldwide. Therefore, if we want to get the SPF value stated on the sunscreen label, we must apply it. However, when applying it, how do we measure it? It may not be convenient in practice. Therefore, here is a rough guideline:
1. Apply sunscreen 2 fingertips or 2 Finger Tip Unit (2 FTU).
According to research, the average adult’s skin area is 1.73 square meters, so if you apply sunscreen to your whole body, you will need about 35 grams. The estimation of skin area is adapted from the medical method used to assess the severity of burns. The facial skin area is estimated using the Rule of Palm, which is 1 palm including fingers = approximately 1% of the skin โปรโมชั่น ufabet area. Let’s say that a person’s face has an area of about 3 palms, which is 3%.
If we compare the rule of three, 100% surface area uses 35 grams of cream. If the surface area is 3%, then approximately 1.05 grams of sunscreen is used.
As for the amount of sunscreen, 2 knuckles are weighed to be equal to 1 gram. 1 unit of FTU or Finger Tip Unit is equal to the amount of cream squeezed from a tube with a diameter of 5 millimeters, starting from the last crease to the tip of the index finger. Therefore, it is reasonable to use no less than 2 knuckles to apply sunscreen to the entire face, and you should squeeze it to fill your fingers or slightly heap it. It is guaranteed that it will not run out.
Another theory is that the face and neck area of an adult human is approximately 685 square centimeters. Using the standard formula of 2mg/cm2, the total amount of sunscreen required is 685 x 2 = 1,370 milligrams, or approximately 1.3 grams, which is approximately 2.5 FTU or 2 and a half fingers.
- Tips: You should divide the sunscreen into 2 rounds, squeezing out 1 finger’s worth of cream each time. Apply all over your face and wait for the cream to absorb for about 3-5 minutes before applying another round.
2. Apply sunscreen with two fingers or 2 Finger Rule Sunscreen.
For applying sunscreen, two fingers come from the 9% rule (Rule of Nines), which divides the skin surface area of our body into 11 parts, each part has an area of 9%, consisting of:
- Head, neck, face
- Left arm
- right arm
- Upper back
- Lower back
- chest
- abdomen
- Front left leg
- Rear left leg
- Right front leg
- Right rear leg
The appropriate amount of sunscreen for each part is 2 fingers. Squeeze the cream from the base of the finger to the tip of the index finger and middle finger. Squeeze it fully, not in a thin line.
In summary, applying sunscreen with two fingers is for the entire face. Applying sunscreen with two fingers is for the entire face and neck, both front and back. Don’t get confused. In addition, there are other ways to estimate the amount of sunscreen to apply, such as applying the entire body using about 1 shot glass or 1 golf ball, applying the entire face using 1/4 teaspoon, 1 nickel or 1 ten baht. However, these methods are more difficult to estimate and have a higher chance of being wrong, while measuring from the fingers is more practical.
How to apply sunscreen correctly
How to choose sunscreen
Applying sunscreen correctly should start with how to choose sunscreen because UV rays include UVA which causes dry skin and premature wrinkles, UVB which causes sunburn, and UVC which cannot penetrate to the earth. Therefore, we should choose sunscreen that can protect against both UVA and UVB by looking at the following:
1. SPF (Sun Protective Factor) indicates protection against UVB. The higher the SPF used, the more effective the protection will be.
2. PA (Protective Grade of UVA) value indicates UVA protection.
PA+ means it protects against UVA 2-4 times.
*PA++ means it protects against UVA 4-8 times.
PA+++ means it protects against UVA 8-16 times.
PA++++ means it protects against UVA more than 16 times.
3. Waterproof / Water Resistance If you choose a waterproof sunscreen, it should say that Water Resistance means waterproof for 40 minutes. Very Water Resistance means waterproof for 80 minutes.
Thailand has a lot of sunshine almost all year round. A good sunscreen should have an SPF of 30 or higher and a PA+++ or PA++++ symbol. If you have to do outdoor activities or sweat a lot, such as swimming, golfing, or tennis, you should use a waterproof sunscreen.
Principles of applying sunscreen
1. Apply sunscreen 15-30 minutes before going out in the sun.
2. Apply sunscreen in an appropriate amount. Squeeze the cream into two knuckles or two fingers for applying to the face and neck. However, if using a liquid or lotion sunscreen, squeeze out about the size of a ten-baht coin.
3. Apply sunscreen to 5 spots on your face: forehead, both cheeks, nose, and chin. Then spread the cream all over your face.
4. Reapply sunscreen in case of heavy sweating and after getting out of the water.
5. Should be reapplied every 2 hours, especially if exposed to strong sunlight.