Racal suit

The Racal suit is a portable, positive-pressure biological suit designed for fieldwork involving extreme biohazards believed to be airborne. Its self-contained air supply and filtered airflow were intended to keep contaminated particles from entering the suit, enclosing the wearer in a controlled protective layer. Used first in the Kitum Cave investigation and later inside the Reston Primate Quarantine Unit, it carried the logic of high-containment work into a cave and a monkey house: places where teams had to operate close to animals while treating the surrounding environment as potentially contaminated.

Design and Function

The Racal suit, also called an orange suit because of its bright color, was lighter than the Chemturion suit and fully portable. A battery-powered air supply drew air from outside, passed it through virus filters, and pushed it into the suit, maintaining positive pressure. The suit surrounded the wearer with filtered air and was described as performing the same protective function as the heavier Chemturion. Its main body, apart from the helmet and blowers, was disposable and could be burned after one or two uses.

In the Reston operation, the suit's protection depended on how it was assembled as well as on its material and air supply. Support personnel taped rubber gloves to the sleeves while the wearer held their arms straight, then taped bright yellow rubber boots over the suit legs to create a seal above the ankles. A clear, soft plastic bubble served as the helmet. These joins were practical vulnerabilities: operators were instructed to patch a rip immediately and to inspect a partner's suit repeatedly, because a damaged suit could lose pressure and allow contaminated air to enter.

The suit also imposed a time limit. Its batteries lasted about six hours, so wearers had to leave the hot area and be decontaminated before their power ran out. In the monkey house, Rhonda Williams's blower stopped and her suit began to lose its shape against her clothing. The team first prepared to evacuate her; a spare battery was then found inside, allowing the equipment to be changed over. The incident showed that the protective boundary relied not only on the suit but also on battery reserves, communication, and a safe route out.

Field Use at Kitum Cave

During the Kitum Cave expedition, the team brought Level 4 containment practices into the field. Researchers wore Racal suits inside the cave, where they marked a route with avalanche poles and placed animal cages along it. Monkeys and guinea pigs were positioned in the cave environment as part of the search for a possible source of Marburg virus. The suit's portability mattered in this setting: the investigators needed protective equipment that could be worn while moving through the cave rather than remaining connected to a fixed laboratory system.

The suits operated within a larger arrangement of work zones. Near the cave, tarpaulins marked a gray area for chemical showers and decontamination, a Level 3 staging area for changing, and a Level 4 necropsy area. Researchers in suits dissected captured small animals under the necropsy tarp and collected blood and tissue for storage in liquid nitrogen. The distinction between these spaces made the suit one part of a controlled sequence: entering the cave, returning through decontamination, and handling specimens in a designated high-containment area.

The field investigation also illustrates what the suit could not do by itself. The team collected insects, rodents, birds, bats, and other animals, but did not trap leopards or take food samples from large animals; permits and practical difficulties shaped those limits. Protective clothing enabled work in the cave, but it could not answer which animal, if any, carried the virus. The expedition's use of the suit therefore joined a technical safeguard to an investigation whose central biological question remained unresolved.

Use in the Reston Operation

When the U.S. Army team prepared to enter the monkey house, it reused some Racal suits that Gene Johnson had brought back from Africa. Jerry Jaax and Captain Mark Haines dressed in the building's staging area, after changing into surgical scrubs. Their suits were fitted and sealed by the support team; they then entered a makeshift air lock between the staging area and the contaminated rooms. The two doors of that corridor were not to be open at the same time, limiting the movement of air between the hot side and the staging space.

Inside, the suit had to function amid conditions that strained both equipment and people. The building's air-handling system was not working, and the temperature was described as exceeding ninety degrees. Jaax's face bubble fogged until he pressed it against his faceplate to clear his view. Teams were told to check neighboring suits for tears every five or ten minutes, take regular breaks, and report fatigue before it led to mistakes. The equipment did not remove the need for disciplined movement, observation, and communication; it made those routines consequential.

The wider operation depended on arranging spaces and procedures around the suits. Gene Johnson had identified an unused storeroom as the staging area and a closed corridor as an air lock, while the back rooms were meant to be sealed off from the offices. That barrier was breached when workers found another route into the back rooms, demonstrating that a suit could protect an individual without making the building's containment plan secure. On entering, Jaax and Haines encountered workers who had reached the area by that route and were not fully protected in the same way. The episode made the difference between personal protection and site-wide containment unmistakable.

Protection, Work, and Limits

The Racal suit appears in two different field settings, but in both it made dangerous work possible by creating a portable barrier around the wearer. In Kitum Cave, it supported movement through an uncertain natural environment and the handling of specimens in a planned decontamination system. In Reston, it allowed Army personnel to enter rooms containing sick monkeys and carry out a sustained operation, while suit checks, rest periods, air locks, and controlled staging areas addressed risks that the garment alone could not manage.

Its protective promise was therefore conditional rather than absolute. Positive pressure depended on a working blower and battery; the suit's seals depended on careful taping and inspection; and the team's safety depended on the building's routes and procedures being followed. The lost-air incident involving Rhonda Williams brought that dependence into focus, while the unanticipated route into the back rooms showed how contamination-control plans could be undermined outside the suit itself. The Racal was not a guarantee against exposure, but a mobile component in a larger system of containment—one whose effectiveness rested on equipment, people, and the spaces between them.