Racal suit
A Racal suit is a protective suit with a powered air-purifying respirator. It consists of a plastic suit and a battery-operated blower with HEPA filters that supplies filtered air to a positive-pressure hood. Racal suits were among the protective suits used by the Aeromedical Isolation Team of the United States Army Medical Research Institute of Infectious Diseases to evacuate patients with highly infectious diseases for treatment.
Originally, the hood was manufactured by Racal Health & Safety, a subsidiary of Racal Electronics located in Frederick, Maryland, the same city where AIT was based. The division of Racal responsible for the suit's manufacture later became part of 3M, and the respirator product line was branded as 3M/Racal.
Components
The main body of the protective suit consists of a lightweight coverall made of polyvinyl chloride, rubber gloves, and rubber boots. Originally, the coverall was in a bright orange color, and the Racal suit was known as an orange suit.The hood is a separate component from the protective suit. The Racal hood is a type of PAPR consisting of a transparent hood connected to a respirator, which is powered by a rechargeable battery. The respirator has three HEPA filters that are certified to remove 99.7% of particles of 0.03 to 3.0 microns in diameter. The filtered air is supplied at the rate of 170 L/min to the top of the hood under positive pressure for breathing and cooling. The air is forced out through an air exhaust valve at the base of the hood. A two-way radio system is installed inside the hood for communication. The AIT later switched from using transparent bubble hoods to butyl rubber hoods.