F. Practical Disadvantages of the Recommended Respirators—NIOSH recognizes that the respirators discussed in the preceding section IV.F have some practical disadvantages when compared to the disposable particulate respirators discussed in the next section (IV.G starting on page 27). Due to the use of powered air forced into their facepieces, these devices generate some background noise and impair voice communication to some degree, and affect a wearer's range of motion. Also, initially these respirators may present an "intimidating" appearance to patients accustomed to the surgical masks currently used in health-care facilities. These characteristics may affect patient care.
Other drawbacks of powered HEPA-filter respirators include the fact that the battery assembly must be recharged for at least 8 hours after each 8 hours of use. However, this problem can be minimized by purchasing multiple battery packs, dual-rate chargers, and establishing a charging station near the locations and procedures that require respirator usage. Additionally, several types of periodic maintenance are required for a powered respirator. The elastomeric facepieces must be periodically cleaned and disinfected, since these facepieces are not discarded after each use. However, extra halfmask facepieces (available in up to two halfmask models, three facial sizes, two types of elastomeric materials, and two headband types) can be purchased at less than $20 each for assignment to individual workers. Thus, one blower-filter unit can be used for numerous workers at different times. It is not necessary to purchase one complete respirator for each health-care-facility worker.
Also, the breathing hose and facepiece assembly must be periodically inspected for damage or malfunction. The blower must be inspected for adequate delivery of air to the facepiece. Other possible disadvantages are the weight and encumbrance of the battery, blower, and filter assembly, which must be worn on a belt at waist level with a 30-inchlong, corrugated breathing tube connected to the facepiece.
Positive-pressure (a.k.a. pressure-demand), air-line, halfmask respirators require an air supply from an uncontaminated compressed-air source as stipulated by OSHA (89). The
