Low enriched uranium is defined as having less than 20 percent U-235. Which choice represents that definition?

Low enriched uranium is defined as having less than 20 percent U-235. Which choice represents that definition?

• A. Less than 20% concentration of U-235
• B. Greater than 20% concentration of U-235
• C. Around 90% U-235
• D. Around 3-5% U-235

Answer: (A)

Understanding enrichment levels means looking at how much U-235 is in uranium. Low enriched uranium is defined by having less than 20 percent U-235. This directly matches the statement that the U-235 concentration is below 20%, which is the hallmark of LEU. In practice, reactor fuel is usually around 3–5% U-235, well under 20%. If the enrichment were above 20%, it would be considered highly enriched uranium, which is a different category with different uses and safeguards. So the option that says less than 20% concentration of U-235 is the correct one. The other options describe higher enrichments or typical LEU ranges but don’t fit the given definition.

Understanding enrichment levels means looking at how much U-235 is in uranium. Low enriched uranium is defined by having less than 20 percent U-235. This directly matches the statement that the U-235 concentration is below 20%, which is the hallmark of LEU. In practice, reactor fuel is usually around 3–5% U-235, well under 20%. If the enrichment were above 20%, it would be considered highly enriched uranium, which is a different category with different uses and safeguards. So the option that says less than 20% concentration of U-235 is the correct one. The other options describe higher enrichments or typical LEU ranges but don’t fit the given definition.