Where can I find the analytical results from drinking water samples?
All RadNet drinking water sampling results are available on the RadNet Envirofacts website. For more information, visit RadNet. Return to Frequent Questions About RadNet.
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All RadNet drinking water sampling results are available on the RadNet Envirofacts website. For more information, visit RadNet. Return to Frequent Questions About RadNet.
More than 60 drinking water sampling locations reported results in the United States in 2018 as part of the RadNet monitoring network. Drinking water samples are typically collected four times a year from taps and are sent to the EPA’s National Analytical Radiation Environmental Laboratory (NAREL) for analysis. Each of…
Under the Safe Drinking Water Act (SDWA), the EPA sets legal limits on the levels of certain radionuclides in drinking water. These limits are applicable to all federal, state and local jurisdictions, including local city public works facilities. Under SDWA, the Agency established a dose-based Maximum Contaminant Level (MCL) for…
RadNet near-real-time air data are refreshed hourly during business hours, Monday through Friday. This hourly refresh ensures that the most up-to-date data are available for the last 24 hours. NOTE: All results are shown in Coordinated Universal Time (UTC). To learn more, visit RadNet. Return to Frequent Questions About RadNet.
The EPA uses RadNet monitors to track fluctuations in gamma radiation emitted from airborne radioactive particles at each air monitoring site. Tracking these changes over time gives a picture of the normal, background levels at each monitoring location and allows EPA scientists to detect any unusual changes. A graph of…
The EPA's RadNet monitors are highly sophisticated devices that occasionally require maintenance and repair. Normally, near-real-time air monitoring data are posted to the RadNet website six times daily. Under certain circumstances a delay in data availability may occur (monitor maintenance or repair, or server/network connection issues). When these situations arise…
Exposure rate is the amount of ionizing radiation per hour in a person’s vicinity (measured in milliRoentgen per hour, mR/h), whereas dose rate is the biological effect on the body from exposure to that radiation (measured in nanoSieverts per hour, nSv/h). As an approximation, a radiological dose rate of 1…
Background radiation exposure rates normally vary from location to location. There are many factors that influence exposure levels, including naturally-occurring radionuclides in the soil and altitude. For example, the exposure rate from naturally-occurring elements in rocks and soils (terrestrial radiation) may vary by more than a factor of 10. For…
Exposure rate measurements indicate the overall level of gamma radiation present in the vicinity of a monitor. The EPA decided to add exposure rate measurement capability to the RadNet system to make monitoring results easier to understand RadNet exposure rate measurements can be compared with results from different RadNet stations…
Under the Safe Drinking Water Act (SDWA), the EPA sets legal limits on the levels of certain radionuclides in drinking water. Under SDWA, the Agency established a dose-based Maximum Contaminant Level (MCL) for beta particle and photon (gamma) radioactivity of 4 mrem/yr. The MCL is based on lifetime exposure criteria…
RadNet air monitors analyze radiation emitted from particulates collected on air filters. These results are presented as a gamma gross count rate measurement. Measuring data in counts per minute allows EPA scientists to detect anomalies by tracking changes over time. For more information, visit RadNet. Return to Frequent Questions About…
It is common to see fluctuations in data at a single location over time due to fluctuations in normal background radiation. Rainfall, snowfall and changes in atmospheric conditions such as pressure or time of day/night may account for variations in measured background radiation levels; some such conditions can cause increases…
The normal background radiation levels in one location may be different from the normal background radiation levels in another. The normal background level of radiation at any one location depends on factors including: Altitude (monitoring data from higher altitude locations may show a higher level of normal background radiation because…
RadNet near-real-time air data are screened at the EPA’s National Analytical Radiation Environmental Laboratory (NAREL) to identify anomalous readings. When an anomalous result is reported, the data are flagged for review by a trained EPA scientist. In instances where further review of the near-real-time data is needed, air filter analysis…
Having a monitoring system in place to screen drinking water for radionuclides ensures that in the event of an emergency the RadNet monitoring system is able to measure radionuclide levels in local water supplies. This is valuable inform which can help to inform decision makers whether protective actions or additional…