Test Your Sunscreen IQ: Notes from a San Francisco Bay Area Dermatologist
Know enough about sunscreens? Test your sunscreen knowledge by taking the following short quiz, recently published in the Skin Cancer Foundation Journal. You may be surprised by how much you do or do not know about this important topic. See answers at the end of the blog.
1. A sunscreen’s SPF, which stands for Sun Protection Factor, measures protections against the sun’s ultraviolet B (UVB) radiation. SPF numbers indicate
a. How long the skin will take to redden in the sun when using the sunscreen, compared to how long the skin would take to redden without sunscreen
b. The percentage of active ingredients in the sunscreen
c. The number of hours you can stay out in the sun
2. A sunscreen with an SPF of 15 protects against approximately 93 percent of the sun’s UVB rays. A sunscreen with an SPF 30 protects against
a. 93 percent of the sun’s UVB rays, and 93 percent of the sun’s UVA rays
b. 97 percent of the sun’s UVB rays
c. 100 percent of the sun’s UVB rays
3. If you apply a sunscreen with an SPF of 20, and then apply another sunscreen with an SPF of 30, what is the total value of the SPF you’ve applied?
a. SPF 25
b. SPF 30
c. SPF 50
4. How many sunscreen ingredients are currently available in the US?
a. 12
b. 15
c. 17
5. Sunscreen ingredients fall into two broad categories, inorganic/physical and organic/chemical. The two inorganic ingredients are:
a. Titanium dioxide and cinoxate
b. Cinoxate and zinc oxide
c. Titanium dioxide and zinc oxide
6. Doctors recommend applying one ounce (two tablespoons) of sunscreen to the body 30 minutes prior to sun exposure, and then again
a. After one hour outside
b. After one hour outside on sunny days
c. After two hours outside
7. Because children have delicate skin, sunscreen should not be used on babies
a. Under three months
b. Under six months
c. Under one year
8. For a sunscreen to provide adequate UVA spectrum protection, it must include one or more of the following ingredients:
a. homosalate, octinoxate, PABA, octisalate
b. avobenzone, titanium dioxide, zinc oxide, ecamsule (Mexoryl)
c. cinoxate, ensulizole, octocrylene, Padimate O
9. Water-resistant sunscreen:
a. Has to be reapplied after 40 minutes in the water
b. Has to be reapplied after 90 minutes in the water
c. Does not need to be reapplied
10. When stored properly, sunscreen should last for how long after the manufacturing date stamped on the package?
a. 9 months
b. 1 year
c. 2 years
Hope you found this quiz fun and educational! Check your answers below.
1=a; 2=b; 3=b; 4=c; 5=c; 6=c; 7=b; 8=b; 9=a; 10=c
Tags: SPF, sun, sun protection factor, sunscreen, titanium dioxide, uva, uvb, zinc oxide
This entry was posted on Wednesday, June 24th, 2009 at 1:32 pm and is filed under Skin Health. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
