With the incident of anthrax mailing in 2001, most federal agencies have realized that mail centers may be a major point of either foreign or domestic terrorist attacks. In this regard, the USPS cannot dismiss that this incident will not repeat and has put various measures to mitigate any risk.

Though the agency has continued to process billions of mails every year, they have put several measures in place in preparation for the worst-case scenarios. Read through the post to discover various USPS mail security measures.

Background of the USPS mail security measures.

The United States postal services are tasked with mail delivery and postal services to every individual, business, residence, and community in the United States, its service personnel overseas, and adjacent territories.

Approximately 800,000 full-time and part-time employees work for the agency in over 38,000 established or leased facilities located across the country and its territories. An example of these facilities is the common post offices providing retail services and mail products to businesses and the public at large.

Other facilities include major mail processing established with tasked with performing automated mail-sorting works; these establishments can be as large as one million square feet and employs thousands of people.

The U.S postal inspection service is the country’s oldest arm that is tasked with ensuring USPS mail security measures and the safety of postal facilities, employees, and assets. The inspection service employs 1,900 inspectors who carry out routine facility reviews known as the Observation of Mail Condition Program (OMC).

The observation of the mail condition program is done during the fall and the start of the winter seasons. In order to address security concerns in time, every postal facility has one security control officer, and every postal location has one area security coordinator.

Generally, the security officer is the head of installation or supervisor and serves as the central point in the implementation of security policies and coordination with the inspection services on matters of security as they may arise.

Potential threats in the mail systems.

There is a broad range of potential security threats that can be directed to the facility through mail centers. Threats involving CBRNE are classified as both disruptive and dangerous.

However, others like threatening letters and white powder hoaxes are only targeted to disrupt the organization's activities or to show dissatisfaction with the facility's or individuals' way of carrying out their operations.

Nevertheless, the facility's screening systems must be optimized so they can identify these threats and reduce or eliminate the risks they pose to the facility, employees, and the routine operations of the postal services. The following sections outline potential threats you need to be on the lookout for.

1. Chemical.

Chemical threats include blood, nerve, pulmonary, industrial, irritants, and blister agents. These categories of threats are hard to detect until they are deployed, and their effects are almost instantaneous.

Generally, chemical threats are available in solid, vapor, or liquid forms and provide various challenges to those deploying them and those trying to identify them during mail processing.

If the intention is to target individuals or the facility, gases and liquid should be controlled with an electronic or remote-controlled device while the package or mail is processed. These USPS mail security measures make use of chemical agents difficult.

However, they can be packaged and delivered through any form of courier any other postal delivery service. Therefore, mail and package screening systems should be able to identify the release and possible containment measures to limit the exposure of targets.

2. Biological.

Since anthrax letters were discovered in October 2001, biological threats have been a common category of mail-borne threats. Additionally, biological agents causing plague, anthrax, tularemia, and smallpox are commonly classified as potential biological email-borne weapons.

As was the case with the anthrax mails, a considerable quantity of these threats can be supplied through the standard envelope. And although this method would need a more complex "bomb" covered in a closed packet, these threats can also be distributed through aerosol sprays.

Owing to their tiny particles, high amount of paper waste, and high level of dust available in most mailrooms, these forms of threats are hard to detect by traditional means. Further, the incubation period of biological threats can take days or even weeks before they are activated.

While longer incubation periods mean that anyone exposed can be successfully treated, it also means that those who are not aware of exposure can stay for long without getting treatment and further complicate the chances of recovery.

Another common that is usually included in the talks about biological threats is the Ricin- a type of poison found in castor beans. The poison can be made from processed castor beans waste matters, meaning it can be readily available for terrorist purposes.

Though the toxic Ricin is not easily absorbed through the skin, it can be fatal if it enters the blood system through a wound or cut. Tiny particles of this poison can also be inhaled through the lungs and can lead to death in less than three days.

This toxicity makes Ricin a potentially fatal threat when delivered deliberately into mail centers.

3. Nuclear/radiological threats.

Radiological threats include ones produced by a nuclear detonation of any kind and those resulting from exposure to unprotected radioactive elements. Also, this threat can be dispersed through making a combination of the traditional explosives and radiation elements to make a "dirty bomb."

People who are exposed to radiation can have immediate or long-term consequences. Radiation detection methods can be used in mail and package screening systems to identify different radiation particles.

However, owing to the difficulty of identifying beta and alpha particles inside packages and mails, most portals and pagers incorporated in the mail centers mostly target gamma particles.

4. Explosives.

Packages and letter mails are all prone to being used as mail bombs. New methods and miniaturization of various explosive components have made it hard to detect letter bombs. This has also increased the level of destruction.

The component similarity between letter bombs and common electronic devices has further complicated the identification process in the mailroom. Luckily, several bomb detection approaches and technologies can be used as USPS mail security measures.

There are a lot of explosives that can be used in parcel and letter bombs. Military issues explosives like “det cord” and C-4, ammonium nitrate and pentaerythritol tetranitrate, PETN have been used before.

Fortunately, bombs or explosives have some characteristics that can be used to identify them quickly. Besides their density and appearance, explosive elements leave vapor trails that can be gathered from packages and letters by the bomb detection team or the current electronic sensors.

Best practices for safe mail handling

Safe-mail handling extends broadly, and different approaches can be used to provide security. Since there is no one-size-fits-all method for safe mail handling, every operation must include security measures to mitigate and address the risks linked to a particular facility.

  • Assessing the risks in mail rooms.

Once a complete assessment has been done on the facility where mail handling operations are based, and proper measures have been put in place or identified for future implementation, the best determinant of safe mail handling practices is the risk assessment on the operations themselves.

The assessment should concentrate on the facility, operations, and processes governing mail handling. The process should include tasks, jobs, and individuals that will most likely be jeopardized in case a dangerous or suspicious package or envelope enters the facility or the postal services’ workplace.

All mail handling facilities have varied security risk levels. Therefore, each facility should depend on its security experts to develop the most effective method to minimize risks and reduce threats and consequences of any incident.

Some measures can be executed right away, while others may need time and a considerable amount of effort. Utmost consideration should be given to the organization’s mission or those of other tenants that can put the facility as the target.

The facility's risk assessment and operations should factor in the urgency and adequacy of the governments' emergency response capabilities.

  • Streamlining operations.

The best way to reduce risks and exposure to the facility and individuals is to centralize mail handling operations at a different place. Centralization reduces costs, minimizes risks, and boosts effectiveness and efficiency.

Streamlining the operations reduces the risks by limiting exposure to fewer people and one location. Also, it reduces cost by preventing redundancy of several mail centers, equipment, and personnel.

Having trained staff working in one location improves efficiency by sharing ideas and faster work rates. Centralizing better equipment significantly improves risk reduction hence leading to improved effectiveness.

The first sorting of mails should be done manually. It is at this point where screening of all mails for malicious or suspicious packages is done. Those used to sorting mails should do the screening task because they can quickly identify any package that doesn't look ordinary.

The manual screening procedure is not foolproof. Mostly, the one who first detects the suspicious item is the recipient. Due to this reason, every facility must supply a list of questionable items indicators to the staff to improve their level of awareness.

  • Personnel training.

Education and awareness are significant factors when it comes to preparedness. Workers must be aware of their environment and the packages they are handling. Carefully design and monitor the security programs to minimize risks at all levels.

Through training, the company develops a culture of preparedness and awareness. Training is important to ensure your staff is confident in what they are doing. And Administrators should make security training a vital factor in the workplace.

A complete training package should include;

  • Setting basic security protocols.
  • Identifying and reporting suspicious mails and packages.
  • Effective ways of using personal protective gear.
  • Responding to various security threats like bombs, biological and radioactive threats.

Keep a record of all staff and the training done, including completion dates. Implement regular refresher training to keep them updated on new procedures.

Besides educating staff in mail centers, you need to offer training to everyone working at the facility on best mail handling practices, including mail security measures. Staff awareness of steps to be taken fosters confidence in handling packages delivered to them.

  • Review your security plans consistently.

Regular exercises and training are crucial to the success of implementing your security plans and policies. Adequately trained employees can reduce the effects of dangerous mail handling. The training should emphasize on life safety, efficiency, security communication, and roles and responsibilities of everyone to minimize risks.

An external facility review of the security policies is highly recommended. It may include peer review, security consultant, or security department.


Since the incident of anthrax letters at the U.S postal service, their agency has put strict measures to combat any potential threats. The threat of any type can cause effects to the mail center and the entire public at large.

These threats range from biological to nuclear and can target individuals or facilities. Owing to this knowledge, there are various USPS mail security measures to combat any signs of suspicious emails.

To reduce the risks of security breaches and increase preparedness at any mail facility, you need to offer adequate training and awareness, assess the risks at mailrooms, centralize mail operations and review the security policies from time to time.