Sunscreen and Expiration Dates Explained. One of the most critical products that I would advocate a client use before any other type of skin care product would be a sunscreen.
http://www.dermalinstitute.com/us/news/2012/04/sunscreen-and-expiration-dates-explained/
What is the expiration date for my product? Cosmetic and skincare products will not have a set expiration date as a product's shelf life may vary based on when it is opened, and how it is used/stored. Instead, skincare products display what is known as the PAO (Period After Opening) symbol. You can conveniently find our PAO labels on the back side of the packaging in the lower left corner. Most of our products are stable 3 years unopened and 12 months after opening. There are a few exceptions that are stamped with an expiration date at the crimp of the tube or bottom of the bottle, and those products are listed below. Additionally, our Resist C15 Super Booster should be used within 3 months after opening and within 6 months from the purchase date.
http://paulaschoice.custhelp.com/app/answers/detail/a_id/304/~/expiration-dates
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https://www.reddit.com/r/SkincareAddiction/comments/24ew5y/where_is_the_expiration_date_on_neutrogena/
If you can figure out when it was manufactured, you should be able to figure out the manufacturing month at least. The first number should be the year (7=2007, 11=2011, etc.) Then A=Jan, B=Feb, for the month. Not sure if it works for Neutrogena, but this is what it was for Banana Boat a couple summers ago.
https://www.reddit.com/r/SkincareAddiction/comments/24ew5y/where_is_the_expiration_date_on_neutrogena/
Sunscreens are designed to remain at original strength for up to three years. This means that you can use leftover sunscreen from one year to the next. Some sunscreens include an expiration date — a date indicating when they're no longer effective. Discard sunscreen that is past its expiration date. If you buy sunscreen that doesn't have an expiration date, write the date of purchase on the bottle and be sure to throw it out within three years. Also, discard sunscreen that has any obvious changes in color or consistency.
http://www.mayoclinic.org/healthy-lifestyle/adult-health/expert-answers/sunscreen-expire/faq-20057957
Unopened: Starts to lose flavor after 110 days. It’s best to store bottles in boxes, and then in dark place. Stronger alcohol and higher levels of hops might extend the shelf life of a beer. One example is Michelob Craft Specialty beers, which are often at their peak with 180 days.
http://www.organizeyourlife.org/Expiration.htm
Question: How do you know if sunscreen has expired? I found a bottle of sunscreen under my cabinet from last year and don't know if it is still good. How do you know is sunscreen has expired? Answer: To determine if sunscreen has expired, first look for an expiration date on the label. Many manufacturers do print an expiration date on sunscreen. If there is no expiration date, you can always call the customer service number listed on the label. You can provide them with the codes that are printed on the bottle and they can tell you if it has expired. The codes printed on the label track the date, batch, and location of where your bottle was manufactured.
https://www.verywell.com/how-do-you-know-if-sunscreen-has-expired-514400
The FDA requires that all sunscreens retain their original strength for at least 2-3 years, and in order to make these claims the sunscreen formula has to undergo a series of real time or accelerated stability tests to prove that the ingredient is still active up until the time of expiration.
http://www.dermalinstitute.com/us/news/2012/04/sunscreen-and-expiration-dates-explained/
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https://www.reddit.com/r/SkincareAddiction/comments/24ew5y/where_is_the_expiration_date_on_neutrogena/
If sunscreens have expired there is a good chance they are still good for a few months; however once you reach the expiration date there is no guarantee that the level of activity is still present. • The best place to store your SPF product is in a cool place out of direct sunlight and heat. • Buy smaller sizes of your SPF product vs. larger “30% extra for free” products, which will inevitably expire before you get a chance to use them all and you’ll end up having to throw them out.
http://www.dermalinstitute.com/us/news/2012/04/sunscreen-and-expiration-dates-explained/
what is the expiration date for spf
The expiration date for Sun Protection Factor is up to three years. Expiration period of SPF is up to three years.