Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Relationship between detection results in different sites. Correlations between two sampling sites. The numbers in the blocks are the correlations between the paired surfaces (p-value <0.05). Blank blocks denote no significant correlation between the contamination results of the paired surfaces.
