Home Store Project Ideas Project Guide Ask An Expert Blog Careers Teachers Parents Students

Don't Get Burned! Measure the UV Index at Different Times of the Day

Difficulty
Time Required Short (2-5 days)
Prerequisites None
Material Availability You will need to order a personal UV monitor online. Please see the Materials and Equipment list for details.
Cost Low ($20 - $50)
Safety Do not look at the Sun when you are measuring the UV level. Wear sunscreen when you are in the sunlight.

Abstract

It's true that the light from the Sun provides the heat and light we need to survive here on Earth, but it also poses a threat. Ultraviolet (UV) rays in sunlight cause damage that can lead to early skin aging and even skin cancer. In this science fair project, find out when you need the most protection from UV rays by using a personal UV monitor to measure how the level of ultraviolet light changes during different parts of the day.

Objective

Measure the change in UV levels over the course of a day.

Credits

David B. Whyte, PhD, Science Buddies

Cite This Page

MLA Style

Science Buddies Staff. "Don't Get Burned! Measure the UV Index at Different Times of the Day" Science Buddies. Science Buddies, 7 Dec. 2012. Web. 21 Oct. 2014 <http://www.sciencebuddies.org/science-fair-projects/project_ideas/HumBio_p028.shtml>

APA Style

Science Buddies Staff. (2012, December 7). Don't Get Burned! Measure the UV Index at Different Times of the Day. Retrieved October 21, 2014 from http://www.sciencebuddies.org/science-fair-projects/project_ideas/HumBio_p028.shtml

Share your story with Science Buddies!

I did this project I Did This Project! Please log in and let us know how things went.


Last edit date: 2012-12-07

Introduction

Comedian Robin Williams once said, "Spring is nature's way of saying, 'Let's party!'". The arrival of spring brings the return of the warmth and light that were in short supply during the winter months. We go to sunny beaches, have picnics, play in the park. But do you try to avoid getting too much Sun exposure? There is a good reason why you should: sunburns! While most of the ultraviolet (UV) light that is produced by the Sun is filtered out by the atmosphere, enough UV light reaches Earth to cause damage to the DNA in the skin cells of unprotected beach-goers. DNA is like a set of instructions that is stored in almost every cell of your body (red blood cells do not have DNA). When you get a sunburn, the DNA is damaged. The damage can cause some of the instructions to change change or be lost, which is not a good thing. DNA damage in skin cells can sometimes lead to skin cancer. UV light can also damage the eyes, contributing to the development of cataracts later in life.

The level of UV light increases during the morning and then peaks at midday. But how does it change? Is the amount of UV light at 10:00 AM 50 percent of what it will be at noon, or perhaps it is 25 percent? In this science fair project, you will determine how the level of ultraviolet light changes during the course of a day, using a personal UV monitor. The monitor has a scale for the UV index that goes from 0 (no UV) to 25 (extreme UV exposure). Once you have measured the amount of UV light at different times during the day, you will graph your results so you can see how the UV light changes over time. After you do this science fair project, you can still enjoy the sunlight on a nice spring or summer day, but you'll know more about how to protect yourself from too much of a good thing!

Terms and Concepts

  • Ultraviolet (UV) light
  • DNA
  • DNA damage
  • Skin cell
  • Skin cancer
  • Cataracts
  • UV index

Questions

  • Based on your research, what is the chemical in the atmosphere that is responsible for absorbing ultraviolet light from the Sun?
  • What are some ways you can protect your skin and eyes from UV light?
  • Under what conditions can you get too much Sun in winter?
  • Based on your research, what is the UV index? Hint: Visit the websites listed in the Bibliography.

Bibliography

For help creating graphs, try this website:

Materials and Equipment

  • Portable UV monitor, such as the Oregon Scientific model # EB612; available from www.amazon.com
  • Lab notebook
  • Timer
  • Graph paper
  • Helper, adult

Disclaimer: Science Buddies occasionally provides information (such as part numbers, supplier names, and supplier weblinks) to assist our users in locating specialty items for individual projects. The information is provided solely as a convenience to our users. We do our best to make sure that part numbers and descriptions are accurate when first listed. However, since part numbers do change as items are obsoleted or improved, please send us an email if you run across any parts that are no longer available. We also do our best to make sure that any listed supplier provides prompt, courteous service. Science Buddies does participate in affiliate programs with Amazon.comsciencebuddies, Carolina Biological, and AquaPhoenix Education. Proceeds from the affiliate programs help support Science Buddies, a 501( c ) 3 public charity. If you have any comments (positive or negative) related to purchases you've made for science fair projects from recommendations on our site, please let us know. Write to us at scibuddy@sciencebuddies.org.

Share your story with Science Buddies!

I did this project I Did This Project! Please log in and let us know how things went.

Experimental Procedure

Before you begin the procedure, read the directions that came with the UV monitor.

  1. Choose a spot that is outdoors and that gets direct sunlight all day long.
  2. Measure the UV index using the UV monitor early in the morning. Try to get the first reading soon after sunrise.
  3. Human Biology Science Project A portable UV monitor.
    Figure 1. A portable UV monitor. The monitor has a UV-sensitive sensor and provides a reading of the UV index from 0 (no UV) to 25 (extremely high UV).

  4. Since you will average your reading over three days, try to perform the tests on days that have similar conditions. For example, choose three sunny days for the tests, if possible.
  5. Point the face of the monitor directly at the Sun.
  6. Push the button labeled "UV."
  7. Hold the UV monitor steady for several seconds until it completes the reading.
  8. Record the date, time, location, and UV index number in a data table in your lab notebook, like the one below.
    1. For location, write down the city from where you take your readings.
    2. Add a column for notes, such as "cloudy," "hazy," etc.

Day 1

DateTimeLocationUV Index 1UV Index 2UV Index 3 UV Index Average Notes
        
        
        

  1. Take two more readings right away so that you have three separate readings for this same time.
  2. Repeat the procedure every hour until sunset. You might want to use a timer so you don't forget when it's been exactly an hour.
  3. Repeat the entire procedure on at least two more days. This will show that your results are accurate and repeatable. Choose days that are sunny.
  4. Now graph the data. You can use graph paper, or graph it online at a website such as Create a Graph.
    1. Calculate the average UV index for each time and record the averages in the data table. To calculate the average, add the three UV index numbers for each time together, then divide by three. Have an adult help you with this step, if necessary.
    2. Graph the UV index on the y-axis and the time on the x-axis.

Share your story with Science Buddies!

I did this project I Did This Project! Please log in and let us know how things went.


Variations

  • Compare the UV index on cloudy vs. sunny days.
  • Compare the UV index in a shady area vs. a sunny area.
  • Keep the monitor horizontal for each reading. How does this affect the amount of UV striking the monitor?
  • Graph your data as percent maximum UV index vs. time. Use 100% for the highest UV index, and calculate the other values as percentages of the maximum. At what time in the morning is the UV index at half maximum?
  • Investigate how the UV index changes during different seasons.

Share your story with Science Buddies!

I did this project I Did This Project! Please log in and let us know how things went.

Ask an Expert

The Ask an Expert Forum is intended to be a place where students can go to find answers to science questions that they have been unable to find using other resources. If you have specific questions about your science fair project or science fair, our team of volunteer scientists can help. Our Experts won't do the work for you, but they will make suggestions, offer guidance, and help you troubleshoot.

Ask an Expert

Related Links

If you like this project, you might enjoy exploring these related careers:

meteorologist pointing at satellite photo of hurricane

Meteorologist

The atmosphere is a blanket of gases, surrounding Earth, that creates our weather. Meteorologists study the measurements and motion of the atmosphere, and changing events within it, so that they can predict the weather. This weather forecasting helps the general public and people who work in industries such as shipping, air transportation, agriculture, fishing, forestry, and water and power better plan for the weather, and reduce human and economic losses. Read more

Looking for more science fun?

Try one of our science activities for quick, anytime science explorations. The perfect thing to liven up a rainy day, school vacation, or moment of boredom.

Find an Activity