Technologies can enable private and government entities to organize their mail security efforts around a similar sequential and integrated approach. Such an approach would allow these entities to resume the processing of non-affected mail as quickly as possible following a mail-contamination incident.

Early Detection

In the 2001 attacks on the mail, anthrax spores were ejected into the air at several postal facilities when high-speed letter sorters compressed the attackers' envelopes and forced spore-contaminated air out of the envelopes, according to Mark Saunders, a spokesman for the Postal Service. Any mail security system must account for a similar possibility.

A logical way to prevent the spread of an airborne contaminant is to install a ventilation and vacuum system that draws air away from pinch points in the processing machinery and then filters the air so that contaminants become trapped instead of circulating throughout the building. One proven solution is high-efficiency particulate air (HEPA) filtration.

Filtration aside, it is essential to detect when a potential hazard has entered the facility. In reality, detection involves two steps: A triggering technology that alerts personnel when a potential hazard may be present and a confirmation technology that identifies the hazard. The simplest form of triggering technology is a particle counter, placed upstream of the HEPA filter, to monitor the size distribution of particles in the air. In mail processing environments, however, particle counters can be subject to "false positive" readings, causing nuisance alarms that erode productivity and cause costly business interruptions.

A more effective triggering system, available commercially, uses a proprietary technology to measure particle sizes while also detecting the presence of living organisms that could constitute a biohazard.

Identifying the Hazard

When an alarm has been triggered, the next step is to pinpoint the cause. The first step toward identification is to secure a sample of the suspected hazard. Here, the most effective tool is a continuously · operating, inline wet sampling process that draws the material into a buffered saline solution, keeping it alive for analysis. In deciding how to analyze the sample, facility owners must weigh the relative importance of speed, specificity and cost.

Quickest and least costly are simple immunoassays that work much like pregnancy tests a strip of paper or a test tube solution changes color if a hazard is present. These fast, simple tests can produce a credible result, but they are not highly sensitive and may not precisely identify the hazard.

A more definitive test is polymerase chain reaction (PCR) monitoring, which tests the sample for signs of known pathogens' DNA. PCR is a mature technology, widely used in biological sciences to identify microorganisms. Tests take about 30 minutes and can simultaneously check for multiple pathogens. The technology requires more training than do immunoassays, but efforts are under way to develop automated PCR systems that are simpler to use.

A third and highly conclusive step is to send a sample to a Centers for Disease Control or a Federal Bureau of Investi-gation certified lab for microbiological culture. This process may take one to three days, assuming the analysis begins immediately upon the sample's arrival.

Neutralization

Neutralization of known hazards is relatively straightforward. The most common sterilizing technique is irradiation with an electron beam, X-rays or gamma rays. This process is highly effective; it generates heat that can melt plastic items, while the radiation itself destroys photographic film and living items such as seeds.

For these reasons, many organizations reserve irradiation for mail known or suspected to be contaminated. Emerging neutralization technologies include surface decontamination methods using ultraviolet rays or ultrasonic waves, while gaseous treatment is generally considered effective for decontaminating buildings.

Integrating Solutions

All these protective measures can work together to ensure a more secure mail system, and all can readily fit with existing mail processes. Except for differences of scope and scale, all are as practical for private entities' mail centers as for postal and government facilities. The technologies do not impede mail handling, since their functions are mostly automatic.

Furthermore, alternative technologies can provide added protection for high-profile potential attack targets such as corporate chief executive officers (CEOs). For example, mail addressed to the CEO, other executives and high-profile employees can be manually opened over a downdraft table that immediately draws air away from the mail handler and into the detection, sampling and filtration system. This system simultaneously protects the mail handler and the intended recipient.

Advancing technology will constantly provide more tools for safeguarding the mail. For instance, postal agencies are exploring more sophisticated mail screening, identification and tracking techniques. One emerging technology would enable postal retail outlets to match time- and date-stamped video images of customers with specific information about what they mailed.

Another area that needs further research for post offices, government and private mailers alike is screening technology for parcels. A tightly sealed parcel can hide its contents more easily than can a paper envelope. However, one technology that shows promise (and is now in testing) uses X-rays at two different frequencies to provide clues to the chemical nature of package contents.

When metals, chemicals and biological substances are exposed to X-rays, they produce different "signature" responses. These signatures, combined with the actual X-ray pictures, can provide valuable clues to what a package might contain.

Sharing responsibility

Businesses, as major points of entry for mail, have significant opportunities to help protect the US mail stream as a whole. Most organizations that deal in large volumes of mail already have well-developed security practices in production facilities, transportation, employee management, mail preparation and mailpiece design. In the future, postal services may designate specific security standards that, when followed, would enable businesses to have their mail specially designated as prescreened.

Though no single technology or series of technologies can guarantee perfect mail security, all the measures described here are effective.

Irene M. Siedlarczyk is a program manager in the Enterprise Mail business area of Lockheed Martin Distribution Technologies in Owego, New York. For additional information, visit www.lmdtech.com.