The Relationship of SPF and UV Protection
CSEF · 2009 Product Science (Physical) (Junior Division Only)
Overview
Objectives/Goals To find a SPF level where the protection provided starts to level off. This will educate others about a safe SPF rating that will protect their skin against harmful UV rays. Methods/Materials Three separate SPF's of sunscreen were utilized: 15, 30 & 50 SPF sunscreen. Hotdogs acted as the human skin. The hotdogs were lathered up with the three types of sunscreen. A fourth group of hotdogs without protection was included to easily determine how much protection the separate SPF's of sunscreen actually provided. These groups of hotdogs were placed into four separate sections labeled with sharpie on a jelly roll pan covered with foil. The hotdogs were set out in the sun for an extended period of time, 7 hours. Each hour the hotdogs were examined, temperature was taken; observations and pictures were also recorded. Results Overtime there was a color and burn difference between each of the four groups. Each SPF provided slightly more protection over the hours. The 30 & 50 SPF sunscreens provided approximately the same amount of protection for the 7 hour period. They were very close! Conclusions/Discussion The different SPF levels of sunscreen have a corresponding difference of protection but the higher SPF levels did not provide a significant difference in protection over the 30 SPF sunscreen. From this knowledge gained, one can infer that 30 SPF is the lowest SPF sunscreen needed for the best protection over a seven hour period.
Summary statement
This experiment provided valid and useful information to people here in southern California by informing them which SPF of sunscreen provides the best protection over an extended period of time.
Help received
A series of questions answered by Dr. Jim Pettit
Competition history
- CSEF 2009
Resources
Related projects
CSEF · 2007
Sizzling Hot Sunscreen: Does a Sunblock's SPF Level Correlate with Its Ability to Block Harmful Rays from the Sun?
CSEF · 2015
Do SPF Levels in Sunscreen Really Matter?
CSEF · 2007
S.O.S. Save Our Skin: Will Sunscreens with Higher SPF Ratings Provide More Protection from Solar Radiation?
CSEF · 2016
Ultra-Protection against Ultra-Violet
CSEF · 2014
The Effect of Sunscreens' Sun Protection Factor (SPF) on Ultraviolet (UV) Solar Beads
CSEF · 2012
Sunscream
CSEF · 2017
Death Rays: Testing the Effectiveness of Different Sunscreen SPFs at Different UV Time Exposures
CSEF · 2015
SPF Test
Closest projects by meaning, across every fair and year in the corpus.
Browse more like this
Source: California Science & Engineering Fair public projects