Type File Geodatabase Feature Class
This digital layer is intended for use by County of San Luis Obispo staff to identify those county areas where homes are more likely to have indoor-air concentrations exceeding the U.S. EPA recommended action level of 4.0 picocuries per liter. This digital layer should assist San Luis Obispo County in identifying areas where indoor-radon testing should be encouraged and public awareness programs may be beneficial.
The digital layer contains polygons (vector format) of those geographic areas in San Luis Obispo County, California, designated as having high, moderate or low potential for homes to exceed the U.S. EPA recommended radon action level of 4.0 picocuries per liter in indoor air. The polygons are shown on the two plates (maps) for California Geological Survey Special Report 208--Radon Potential in San Luis Obispo County, California.
Churchill, R.K., 2008, Radon Potential in San Luis Obispo County, California; California Geological Survey Special Report 208, 72 p., and 2 map plates. Report available for viewing and downloading on line at: https://www.conservation.ca.gov/
This map layer is intended for use by county of San Luis Obispo staff to identify portions of their county where homes are more likely to have indoor-air radon concentrations exceeding the U.S. EPA recommended radon action level of 4.0 picocuries per liter (pCi/L). The three radon zone categories indicate the likelihood of a home having indoor-radon concentrations at or above the 4.0 pCi/L action level: High (≥ 20 percent), Moderate (5 to 19.9 percent, and Low (< 5 percent). The map layer does not provide specific information about the indoor-radon concentration of a home at any given location within a zone. The only way to accurately determine the indoor-radon concentration within a home at any location is by testing the indoor-air of that home. This can be done by the homeowner using inexpensive testing devices which are sent to commercial laboratories for evaluation or by certified radon testing professionals. This map layer is designed to be used at a map scale of 1:100,000 and not more detailed scales. At this scale it is not unusual for geologic unit boundaries (and, consequently, corresponding radon zone boundaries) to have accuracy limitations of plus or minus tens to several hundred feet and sometimes more. Consequently, radon zone classifications are less certain for locations nearer zone boundaries. CGS does not guarantee the accuracy of radon potential limitations for property parcels based on this map.
| West | -121.347915 | East | -119.466530 |
| North | 35.803009 | South | 34.890833 |
| Maximum (zoomed in) | 1:5,000 |
| Minimum (zoomed out) | 1:150,000,000 |
Churchill, R.K., 2008, Radon Potential in San Luis Obispo County, California; California Geological Survey Special Report 208, 72 p., and 2 map plates. Report available for viewing and downloading on line at: https://www.conservation.ca.gov/
publication date
This map layer is intended for use by county of San Luis Obispo staff to identify portions of their county where homes are more likely to have indoor-air radon concentrations exceeding the U.S. EPA recommended radon action level of 4.0 picocuries per liter (pCi/L). The three radon zone categories indicate the likelihood of a home having indoor-radon concentrations at or above the 4.0 pCi/L action level: High (≥ 20 percent), Moderate (5 to 19.9 percent, and Low (< 5 percent). The map layer does not provide specific information about the indoor-radon concentration of a home at any given location within a zone. The only way to accurately determine the indoor-radon concentration within a home at any location is by testing the indoor-air of that home. This can be done by the homeowner using inexpensive testing devices which are sent to commercial laboratories for evaluation or by certified radon testing professionals. This map layer is designed to be used at a map scale of 1:100,000 and not more detailed scales. At this scale it is not unusual for geologic unit boundaries (and, consequently, corresponding radon zone boundaries) to have accuracy limitations of plus or minus tens to several hundred feet and sometimes more. Consequently, radon zone classifications are less certain for locations nearer zone boundaries. CGS does not guarantee the accuracy of radon potential limitations for property parcels based on this map.
The 1:100,000-scale radon zone polygon boundaries are based on geologic units from the 1:100:000-scale digital geologic map compilation for San Luis Obispo County by Rosenberg in 2007. The digital layer of radon potential zones was produced using MapInfo Geographic Information System software and translated to ESRI Shapefile format.
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Feature geometry.
ESRI
Coordinates defining the features.
Unique identification number for each radon zone in the study area.
The chance a home within a given radon zone would have a test result where the U.S. EPA would recommend fixing that home to lower the radon level. Possible zone potentials are: Very High, High, Moderate, Low and Unknown. Please refer to the related report for details.
An area where a certain percentage of homes are likely to need action to reduce radon levels. Please refer to the related report for details.
The geographical region covered by the report.
The report identification number.
Report descriptive name.
URL to report.
Addition information that is relevant to the data presented here.
Length of feature in internal units.
Esri
Positive real numbers that are automatically generated.
Area of feature in internal units squared.
Esri
Positive real numbers that are automatically generated.
The digital layer was produced to be utilized by San Luis Obispo county government.