Racal suit
.
- For the full-body lab garment with similar purpose, see Positive pressure personnel suit.
A powered, air-purifying respirator (PAPR) is a respirator in the form of a hood, or full-face mask, which takes ambient air that is contaminated with one or more types of pollutant or pathogen, actively removes a sufficient proportion of these hazards, and then delivers the clean air to the user.
Description
There exist different types of PAPR units for different environments. Regardless of type, a PAPR consists of a mask or hood, a powered fan (which forces incoming air through one or more filters for delivery to the user for breathing), and a battery or other power source. The fan, filter, and power-pack may be carried around freely by the user, often secured by a belt around the waist. Alternatively, with certain units, the air is fed to the user via tubing while the fan and filters are remotely mounted.
Filters
The type of filter incorporated into a PAPR must be appropriate to the contaminants that need to be removed. Some respirators are designed to remove fine particulate matter such as the dust created during various woodworking processes. When used with high-efficency particulate air (HEPA) filters, airborne particles containing pathogens (viruses, bacteria) smaller than 5 microns will be removed. When used in combination with the correct filters, PAPRs are suitable for working with volatile organic compounds such as those used in many spray paints. At the same time filters that are suitable for volatile substances must typically have their filter elements replaced more often than a particulate filter. In addition there is some confusion over terminology. Some literature and users will refer to a particulate filtering unit as a dust mask or filter and then use the term respirator to mean a unit that can handle organic solvents.
Example
.
The commercial product known as the Racal Suit — or Racal Space Suit or AIT field-protective suit[1][2] — is a portable personal protective equipment consisting of a plastic suit and a PAPR fitted with HEPA filters that supply filtered air to a positive-pressure hood (also known as racal hood). Racal suits were used by Aeromedical Isolation Teams (AIT) to evacuate patients with highly infectious diseases for treatment.[3][4]
Components
- Protective suit
The main body of the protective suit consists of a lightweight coverall made of polyvinyl chloride, rubber gloves, and rubber boots.[2][5] Originally, the coverall was in a bright orange color, and the racal suit was known as the orange suit.[6]
- Hood
The hood is a separate component from the protective suit. The racal hood is a type of powered air purifying respirator 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 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.[2][3]
Originally, the hood was manufactured by Racal Health & Safety, Inc. located in Frederick, Maryland, the same city in which the AIT unit of the United States Army Medical Research Institute of Infectious Diseases was based.[4] 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.[7][8] The AIT later switched from using transparent bubble hoods to butyl rubber hoods.[5]
Procedures
The main purpose of the AIT was to evacuate a patient from the field to a specialized isolation unit. AIT members were trained to take a bathroom break before suiting up, since the time they would be in the suits could be 1 hour and 45 minutes for a training session and 4 to 6 hours for an actual mission.[9] The patient was placed in a mobile stretcher isolator during transit. After the patient was delivered to the isolation unit, the members would leave the unit and enter into an anteroom with an airlock. They were then sprayed with glutaraldehyde solution to disinfect before the suit was cut away and sent to an on-site incinerator for complete destruction.[10]
References
- ^ "Racal space suit". McGraw-Hill Concise Dictionary of Modern Medicine. Retrieved 15 April 2015.
- ^ a b c Christopher, George (April 1999). "Air Evacuation under High-Level Biosafety Containment: The Aeromedical Isolation Team". Emerging Infectious Diseases. 5 (2): 241–246. doi:10.3201/eid0502.990208. Retrieved 17 April 2015.
- ^ a b "The threat to the United States from Emerging Infectious Diseases, Hearing before the Committee on International Relations, House of Representatives". 30 July 1997: 9. Retrieved 15 April 2015.
{{cite journal}}: Cite journal requires|journal=(help) - ^ a b Sidell, Frederick R.; Takafuji, Ernest T.; Franz, David R., D.V.M. (1997). "19". Medical Aspects of Chemical and Biological Warfare. Office of The Surgeon General Department of the Army, United States of America. Retrieved 15 April 2015.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ a b Marklund, LA (2002). "Transporting patients with lethal contagious infections". International journal of trauma nursing. 8 (2): 51–3. PMID 12000908.
- ^ Preston, Richard (1994). The Hot Zone. Anchor (Random House). ISBN 0385479565. Retrieved 15 April 2015.
- ^ "Racal Health & Safety to be sold to 3M for GBP432 mil". Telecompaper. No. 5 December 1997. Retrieved 17 April 2015.
- ^ "NIOSH Respirator User Notice". The National Personal Protective Technology Laboratory (NPPTL). 12 June 1998. Retrieved 17 April 2015.
- ^ Fleming-Michael, Karen (28 September 2005). "Training Day". Comprint Military Publications. Retrieved 17 April 2015.
- ^ Hamblin, James (26 October 2014). "21 Days". The Atlantic. Retrieved 17 April 2015.