TEPC How do astronauts know how much radiation they are receiving while they are in the ISS? There are many types of monitoring devices that can aid the astronauts in the detection of radiation. These detection devices can be used in space or on Earth. One suck monitoring device is called the TEPC (Tissue Equivalent Proportional Counter). It is a little larger than a Game Boy and has a cell filled with low-pressure propane gas. This hydrocarbon gas is used to stimulate the hydrocarbon content of a human cell. When radiation passes through the counter, and appropriate radiation quality factor can be estimated to see how much radiation the astronaut has received. It will be important for this mission that you are able to collect the data from the TEPC and graph it. By graphing this data, you will be able to estimate the doses for the astronauts at certain times. When graphing, you need to watch that all units are the same. For example, when data is collected, some data may be collected every hour. Some data may be collected every 15 minutes. You must be certain that all conversions are made before you being to graph. Here is an example: How many minutes are in 15 hours? Therefore, if you are graphing in minutes, this would be the way to convert hours to minutes. The TEPC reports data in mRems/min. It ill be your job to graph the TEPC readings. Once the readings are graphed, it will be your job to check the space exposure limits to see if the astronauts will exceed these limits. If you find that the numbers are getting close to exceeding theses limits, you will need to make recommendations to the astronauts about how to decrease their exposure limits. You will once again need to use conversions due to the data being recorded in mRem and the exposure limit chart recorded in rems. Use the following chart for theses conversions: (see chart)

• The Campfire • Acute Effects of Radiation • TEPC