Emission Security

Definition of Emission Security

Emission Security (EMSEC) is a subset of Communications Security (COMSEC) that focuses on preventing unintended or unauthorized reception and interpretation of electronic signals emitted by communication systems or devices. This is achieved through measures that control the emanation of these electronic signals, thereby reducing the potential for interception and exploitation. EMSEC plays a vital role in protecting sensitive data and maintaining the confidentiality of communication channels.


Emission Security in phonetics is: /ɛˈmɪʃən sɪˈkjʊrɪti/

Key Takeaways

  1. Emission Security focuses on preventing unauthorized interception and exploitation of data transmitted through electromagnetic signals.
  2. Two primary components of Emission Security are Communications Security (COMSEC), which protects transmitted data, and Electronic Security (ELSEC), which safeguards electronic emission systems from interference or tampering.
  3. To maintain Emission Security, it’s crucial to implement strong encryption, use secure communication channels, limit emitted signal strengths, control physical access to systems, and provide continuous monitoring and assessment of potential threats.

Importance of Emission Security

Emission Security (EMSEC) is a vital aspect of information security that focuses on safeguarding the unintentional release of sensitive information through electronic emissions or signals from various devices and hardware components.

As technology has advanced, so has the potential for unauthorized parties to intercept and exploit electronic emissions, posing significant threats to privacy and confidential data.

EMSEC plays a crucial role in mitigating this risk by implementing appropriate countermeasures, such as shielding, reducing or filtering electronic emissions, that maintain the confidentiality and reliability of the information being transmitted or stored.

By ensuring emission security, individuals and organizations can protect their valuable digital assets from being compromised or exposed to malicious actors, thereby preserving their privacy, ensuring the integrity of their data, and contributing to overall cybersecurity efforts.


Emission Security (EMSEC), an integral aspect of communication security (COMSEC), serves to protect valuable information by controlling the unintentional release of potentially compromising data through electromagnetic and other types of radiations. This transmission of sensitive information may occur as a result of eavesdropping on the emissions from electronic devices or through the interception of signals from wired communication systems, which could expose organizations and individuals to potential threats.

EMSEC is particularly vital in safeguarding government, military, and private entities where data security is paramount for maintaining strategic advantages, public safety, and business confidentiality. The purpose of EMSEC extends to both securing communication systems and minimizing the risks associated with emanations from electronic equipment.

It encompasses a diverse set of practices, including proper shielding of electronic devices, monitoring for suspicious emissions, and the application of TEMPEST standards to ensure that devices are designed and tested to minimize compromising emanations. By addressing these vulnerabilities, EMSEC not only aids in deterring adversaries from capitalizing on leaked information but also allows organizations to safeguard their critical missions and maintain a competitive edge.

Utilizing EMSEC practices demonstrates a commitment to information security and ensures that communication networks remain resilient against potential security breaches and cyber threats.

Examples of Emission Security

Emission Security (EMSEC) is the protection that results from taking various measures to prevent unauthorized access to sensitive information by intercepting and analyzing electromagnetic signals. It involves shielding electronic equipment and signals from eavesdropping or interception. Here are three real-world examples of EMSEC technologies:

TEMPEST: TEMPEST is a standard of certification in communication systems established by the US government to protect electronic equipment from compromising emanations. The technology focuses on reducing unintentional radiated emissions from electronic systems to a level below detectable or exploitable ranges. High-security organizations, such as military installations and diplomatic offices, often use TEMPEST-rated equipment to maintain secure and confidential communication.

Faraday cages: A Faraday cage is an enclosure made of conductive material designed to block electromagnetic fields. It can be used to prevent unauthorized access to sensitive information by shielding electronic devices, such as mobile phones or computers. Faraday cages are used in secure facilities and research labs where extracting delicate data or protecting electronic equipment from external interference is imperative.

Electromagnetic shielding paint: Electromagnetic shielding paint is a type of specialized paint that contains conductive metals, such as copper or nickel. When applied to walls, ceilings, or floors, this paint forms a shielding layer that reduces the transmission of electromagnetic signals. This measure helps prevent eavesdropping on electronic devices and communication systems within the shielded area. It is particularly useful in scenarios where traditional shielding methods may not be feasible or practical, like the renovation of existing buildings or rooms that require EMSEC.

Emission Security FAQ

What is Emission Security?

Emission Security, also known as EMSEC or Emanation Security, is the process of preventing unauthorized interception and exploitation of classified information that could potentially be leaked through electromagnetic or acoustic emissions.

Why is Emission Security important?

Emission Security is important to protect sensitive information from being intercepted and exploited by unauthorized sources. It ensures that the technologies being used by organizations, especially in critical sectors, are secure from potential eavesdropping and infiltration.

What are some common Emission Security measures?

Common Emission Security measures include shielding of electronic devices, grounded and shielded cables, proper installation of electronic equipment, and implementing TEMPEST standards to prevent radiation of information-carrying signals.

What is TEMPEST?

TEMPEST is a National Security Agency (NSA) specification and NATO certification referring to the protection measures taken to limit the unintentional release of compromising information through electrical, mechanical, or electromagnetic emissions. TEMPEST provides a set of standards and requirements to secure these emissions and prevent unauthorized interception.

How does Emission Security differ from Information Security?

While both Emission Security and Information Security aim to protect sensitive information, Emission Security focuses specifically on the prevention of unauthorized interception of information through emissions, whereas Information Security covers a wider range of protection measures including data storage, access control, encryption, and network security.

Related Technology Terms

  • Signal masking
  • Electromagnetic shielding
  • TEMPEST security standards
  • Compromising emanations
  • Electromagnetic interference

Sources for More Information


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