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Mail Security

​​​​Screening Mail

Since September 11, 2001 and with growing concerns about the safety of our mail, the DMMS has prepared new policies and procedures for screening all incoming USPS mail.

  1. All mail is screened by the Mail Customer Service Branch personnel as it enters the NIH mail system. For this reason, mail should not be accepted from any sources other than DMMS.
  2. Even though mail is initially screened by DMMS each IC should establish procedures to screen incoming mail and report anything suspicious to the proper authorities.
  3. If a suspicious letter or package is identified:

    • DO NOT OPEN or handle excessively by squeezing, shaking, smelling, etc.
    • Isolate the item, if possible by placing it in a plastic bag and moving it to a location away from the immediate work area.
    • ​Immediately notify the proper authorities

Suspect Letters and Packages Illustrations

The Division of Mail Management Services is taking specific precautions and being extra vigilant with the mail, packages and other items. The illustrations on the following two pages represent general checklists for suspect letters and packages. These lists are not all-inclusive and additional items could also identify a mail piece as suspicious. Common sense must prevail at all times. The presence of one or even two of the items on these checklists does not automatically mean the mail is a threat.

Suspect Letter and Package Checklist

Every NIH staff member should be cautious and vigilant for suspicious mail. This checklist will help to identify suspicious mail, packages, or other items:

  • Is the addressee familiar with the name and address of sender?
  • Package/letter has no return address
  • Is the addressee expecting the package/letter? If so, verify expected contents
  • Improper or incorrect title, address, or spelling of addressee name
  • Title but no names
  • Wrong title with name
  • Handwritten or poorly typed addresses
  • Misspelling of common words
  • Return address and postmark are not from the same area
  • Stamps (excessive postage, unusual stamps) versus metered mail
  • Special handling instructions (special delivery, open by addressee only, etc)
  • Restrictive markings such as confidential, personal, etc
  • Over wrapped, excessive securing material such as tape, string or wrappings
  • Oddly shaped or unevenly weighted packages
  • Lumpy or rigid envelopes (stiffer than normal, heavier than normal, etc.)
  • Lopsided or uneven envelope
  • Oily stains or discolorations
  • Item is leaking powder or an oily substance
  • Strange odors
  • Protruding wires or tinfoil
  • Visual distractions (drawings, unusual statements, hand drawn postage, etc)

Suspect Letter and Package Indicator Graphic - Please print this Department of Health and Human Services flyer to use as a handy reference.​

Please be advised that this is only a general checklist. There are processes in place at NIH to deal with suspicious mail incidents. Employees should not attempt to address a suspicious incident on their own. NIH employees on campus and in local off-campus facilities should both call 911 (not 9-911) to notify NIH emergency response staff about suspicious mail or the release of suspicious material from mail and packages.

Any questions? Need assistance? Please contact the Mail Customer Service Branch (MCSB) on 301-496-3586 or through email at