The survey unit sizes in MARSSIM are not intended to be prescriptive. However, MARSSIM does offer one possible set of survey unit sizes, primarily as an example. For Class 1 survey units, MARSSIM suggests survey unit sizes of 100 m² for structures and 2,000 m² for land areas. For Class 2 survey units, MARSSIM suggests survey unit sizes between 100 and 1,000 m² for structures, and between 2,000 and 10,000 m² for land areas. However, these survey unit sizes are not intended to be prescriptive. For Class 3 survey units, MARSSIM does not suggest a limit for either structure or land areas. Section 4.6 of MARSSIM Chapter 4: Preliminary Survey Considerations recommends limiting survey units based on classification, exposure pathway modeling assumptions, and site-specific conditions.

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

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