Monitoring Results from San Juan, PR
RadNet stationary air monitors measure gamma radiation emitted from airborne radioactive particles as they collect on the monitor’s filter.
On this page:
Gamma Gross Count Rate
EPA uses RadNet monitors to track fluctuations in gamma radiation emitted from airborne radioactive particles at each of our sites. Tracking these changes over time gives a picture of the background (normal) levels and allows EPA scientists to detect any unusual changes.You can see a more detailed view of gamma detection across nine different energy ranges in our Gamma Gross Count Rate (by Energy Range) Graph.
Notes on the Graph
- The Gamma Gross Count Rate shows how many gamma rays the monitor detects each minute.
- There may be gaps in the data due to instrument maintenance/repairs, telecommunication disruption, server unavailability or other technical issues.
- Gross gamma count rates may differ from monitor to monitor due to:
- Cosmic radiation (increases with altitude)
- Terrestrial radiation (types of radionuclides in the soil and building materials near the monitor)
- Precipitation (increases in the deposition of radon and thoron decay products deposited around the monitor)
- To view the individual data points shown on this graph, please use the query tool to search the RadNet database in EPA's Central Data Exchange.
- More information about air monitoring data.