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Radiation Protection

What value should I use for the LBGR, if there is no prior survey information?

When no other information is available, MARSSIM suggests a default value for the LBGR equal to ½ the DCGLW. After this, begin the iterative process described in "How do I choose the LBGR?"

For more information on the MARSSIM process, visit Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM).

Return to Frequent Questions about Radiation Regulations, Guidance and Compliance.