Sunburn is caused by UV radiation, either from the sun or from artificial sources, such as tanning lamps, welding arcs, or ultraviolet germicidal irradiation. It is a reaction of the body to direct DNA damage from UVB light. This damage is mainly the formation of a thymine dimer.xcessive UV radiation is the leading cause of primarily non-malignant skin tumors. Sunscreen is widely agreed to prevent sunburn and some types of skin cancer. Clothing, including hats, is considered the preferred skin protection method.
A protractor is used to measure angles. When surveying a theodolite is used. There are a number of tools on the market that perform angle measurement. A <b>protractor</b> is used to measure angles.<br />When surveying a <b>theodolite</b> is used.<br />There are a number of tools on the market that perform angle measurement. Minor edit?
Surveying has three different components, measuring dis-tance, angles and elevation. Each piece of surveying equipment can be used to measure one or more of these components, but determining the piece of equipment that best suit the application can some-times be overwhelming for a person with a limited survey-ing experience. Listed are the various types of surveying equipment and their uses.