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Fire/rescue respiratory protection

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    PPE Update
    by Jeffrey O. and Grace G. Stull
    Sponsored by Globe
    Preparing for the Worst

    By Jeffrey O. and Grace G. Stull

    With the World Health Organization declaring swine flu a pandemic, are we now any more prepared for this new medical threat than we have been in the past? If the spread of swine flu shows anything, it illustrates the difficulty in preventing disease outbreaks based on containment. The containment efforts that did occur were implemented after the spread was identified and always in a knee jerk reaction; meanwhile, the spread of the H1N1 virus is still continuing globally.

    The inability to completely quarantine diseases in our society, and the need for services to be available, raises concerns for how emergency responders who are required to interact with the public can protect themselves. Firefighters and other first responders do come into contact with the public and will be called upon for providing medical aid. While most firefighters are familiar with self-contained breathing apparatus in providing respiratory protection on the fireground for emergencies involving immediate danger to life and health conditions, they are certainly less familiar in dealing with threats from airborne diseases.

    The Center for Disease Control (CDC) recommends facemasks and respirators as PPE for protecting individuals from H1N1 viral exposure, with specific use based on categories related to the setting and individual risk. Facemasks are essentially surgical masks, which are defined as medical devices for infection control. They do not provide respiratory protection and are only intended to block large droplets.

    Although the transmission modes for flu are not completely characterized, airborne pathogenic diseases are typically spread through individuals breathing aerosols (small droplets of liquid suspended in air as would occur when someone sneezes or coughs) or when an individual touches a contaminated surface and then touches his or her mouth, nose, or eyes where mucous membranes are present. Although CDC admits their shortcomings, the choice of facemasks is surprising as facemasks are not respirators and should never be relied upon to provide respiratory protection.

    The respirators recommended by CDC are N95 filtering facepieces. Filtering facepieces are the disposable respirators that are common in a variety of occupational settings. The "N95" designation refers to a classification for use with non-oily particles (aerosols) with 95 percent effectiveness in filtering particles typically found in the respiratory ranges (0.3 to 5 microns).

    The IAFF questions this recommendation, as CDC admits that it does not have the supporting documentation to validate the effectiveness of these respirators in preventing the penetration of small diameter aerosols that could contain H1N1 virus. Some research has been done on the behalf of the government that shows that testing with ordinary particles may simulate viral aerosol penetration, but none of this testing has been specific to flu virus.

    More importantly, why would anyone want to use a respirator that knowingly permitted 5 percent of the challenge to pass through? The relative amount of virus capable of causing disease is not established, but there are potentially millions of virus in an aerosol cloud released by sneezing and coughing.

    The IAFF points to a French study where N95 filter media was used in animal studies for simulating the protection of individuals against avian flu and all the test animals died. The overall effectiveness of these respirators becomes even worse when one considers the poor fit factor of N95 respirators on an individual's face. Just as surgical masks do not prevent contaminated air from passing by the edges of the facemask, many N95 respirators do not seal well against the wearer's face.

    This is because the respirator does not conform properly to the individual, and leakage pathways are established. Upon inhalation, a poorly fitted respirator will allow outside air to enter the mask, providing yet another avenue for exposure. Since the government only establishes the effectiveness rating for filtering facepieces on the basis of material tests alone (not evaluating the complete facepiece and its fit on the face), the actual effectiveness of these respirators is quite likely much lower than 95 percent in preventing exposure to contagious aerosols.

    The IAFF has recommended that firefighters wear a minimum of a different type of respirator known as a P100. In this case, the "P" refers to any type of particle, oily or non-oily ? oil proof. The "100" part of the designation indicates that the filter media is 99.97 percent effective in preventing the passage of particles as tested in government regulations.

    Moreover, these types of respirators are more likely to be equipped with elastomeric seals and able to provide better fit on a variety of face shapes, which in fact has been demonstrated in government research. There are also reusable elastomeric facepieces in air-purifying respirators (APRs) and powered air-purifying respirators (PAPRs) that can be used with suitable filters. APRS can be provided with P100 filters while High Efficiency Particulate Air-Purifying (HEPA) filters are available for PAPRs.

    It is disappointing that better information is not available for first responders in preparing for potential pandemic exposures that are likely to arise - if not this coming flu season, then at some point in the future. While containment measures, universal precautions, and hand washing are essential for stemming the spread of flu diseases, correct PPE selection and use is key part of preventing exposure for first responders that must come in contact with potentially infected individuals.

    Just because this nation has stockpiled tens of millions of N95 respirators and surgical masks, does not make these products effective or appropriate. Rather, first responders should take the necessary steps of ensuring that their exposure becomes negligible as much as possible by using highly efficient respirators that are properly fitted for each individual and action plans for their proper implementation. It may be just a matter of time before we face a truly worst case scenario, one that we surely could prepare for now.

    Sponsored by Globe

    Jeffrey O. and Grace G. Stull are president and vice president respectively of International Personnel Protection, Inc., which provides expertise on the design, evaluation, selection and use of personnel protective clothing, equipment and related products to end users and manufacturers. They are considered amongst the leading experts in the field of personal protective equipment. Send questions or feedback to Jeff or Grace at