EMSEC in a Nutshell

OFFUTT AIR FORCE BASE, Neb. -- Unreported compromise of classified documents led to deadly ambush of top U.S. officials in Iraq

Though the headline above is fictional, the scenario could be all too real.

Could you have been the reason why our adversaries gained access to classified information? Do you know what your responsibilities are when working in a classified processing area?

Knowing just a little bit about emission security could arm you with some powerful tools to help prevent this headline. EMSEC protection results from all measures taken to deny unauthorized personnel national security information that might be derived from emanations from communications equipment.

Compromising emanations are unintentional electronic signals which, if intercepted and analyzed by an adversary, would disclose the classified information transferred or processed by any information systems or telecommunications systems.


Anyone working with electromechanical, electromagnetic, electronic equipment or automated information systems process classified information should be sure that the equipment or AIS is not an EMSEC hazard or risk. To do this, you should know the nature of the problem and be aware of potential EMSEC hazards by having an EMSEC assessment conducted on each classified processing area.

An EMSEC assessment, conducted by your local host base or wing EMSEC manager, determines the need for EMSEC countermeasures for equipment and/or systems in a facility that processes classified information. An EMSEC assessment is a tool used by EMSEC managers to identify required countermeasures and specific red or black installation guidelines according to established criteria and standards. Factors considered during the assessment include classification level and the volume of the information processed.

If you make any changes to the area used to process national security information or are setting up a new classified processing area, you will need to contact your host base or wing EMSEC manager. Normally, unclassified systems do not require EMSEC assessments unless they are in close proximity to equipment or systems processing classified information. If this is the case, the user should advise their unit information systems security officer, who will inform the wing EMSEC manager that classified information will be processed within your facility. Identify the make, model and manufacturer of all equipment used to process classified information, e.g., CPUs, monitors, printers, cryptographic equipment, etc. Provide the EMSEC manager with maps, drawings and diagrams of the facility to include floor plans and equipment layouts. Maps or drawings should indicate what agencies, activities or entities are around the Air Force facility processing classified information, government or civilian. Distances are important.

The preliminary information provided by the ISSO to the EMSEC manager is intended to start the EMSEC assessment process by helping the EMSEC manger prepare for the actual facility, site, system and equipment assessment.

Much of the information associated with EMSEC is classified. For example, when the AF Form 4170 is filled-in, it is classified at minimum "confidential." Any information that identifies an EMSEC vulnerability or weakness in a facility or system will always be classified. If in doubt, play it safe and visit your Wing Information Assurance Office and discuss classification issues with your responsible EMSEC manager. At the very minimum, assessments should be marked "For Official Use Only." In most cases, the completed AF Form 4170s are maintained by the wing EMSEC manager and are available for review upon request.
Remember, if you work with classified processing equipment you have a responsibility to prevent the unauthorized disclosure of classified information through the interception of classified emanations. It's everyone's responsibility to ensure an EMSEC assessment has been completed for all classified processing areas and that all prescribed counter measures are maintained. That's EMSEC in a nutshell.

If you have any questions regarding this information please contact your unit ISSO or your wing information assurance office.