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Audiometric data base analysis (ADBA) offers the most direct means of judging the effectiveness of a hearing conservation program (HCP) in preventing occupational hearing loss. However, numerous factors need to be accounted for if the findings are to be meaningful. This paper discusses several parameters known to influence the interpretation of group data statistics in assessing HCP effectiveness. Testing factors that affect the stability of the data base include audiometric techniques, calibration procedures, testing environment, and the motivation and prior experience of the subject. Pertinent population parameters include age, sex, race, current and prior noise exposures, learning effects, and the types of hearing protectors in use. Two case histories are presented to illustrate the application of ADBA techniques. Specific analysis procedures reviewed include comparisons of mean thresholds for selected industrial and nonindustrial populations, rates of change in mean hearing levels over a period of time, baseline and sequential test-retest comparisons, and different threshold shift criteria. The preliminary results of ADBA research being done by the American National Standards Institute (ANSI) S12.12 Working Group are summarized, including desirable criterion ranges for several statistics established by applying them to control data sets.

Workers need to know why they wear respirators. And their use of protective equipment must always be supervised and governed by written procedures.

Several types of commercially available respiratory filter/sorbent combinations were tested in a coke oven environment. The percent penetration of benzene soluble particulate and benzo(a)pyrene through these filters was determined and was generally found to be less than ten percent. Degradation of filtering efficiency was noted with some types of filters. The use of a sorbent cartridge in conjunction with a covering filter did not significantly change penetration of the contaminants which were measured.

Seven different types of protective sports eyewear were tested to determine whether peripheral awareness as measured with a visual performance task were affected. Goldmann perimetry and the Wayne Saccadic Fixator with Stik-Up attachments were utilized in a repeated measures research design. The sports glasses did restrict visual field, but no one pair of glasses were least restrictive. The restrictions did not translate into significant differences on the performance task. Peripheral visual factors should be taken into account when prescribing protective sports eyewear. The importance of proper eye protection in sports is also discussed.

The paper presents results of measurements of the efficiency of retention of radon decay products, occurring as radioactive aerosols, by anti-dust masks. The efficiency of three types of masks: PM-1, PM-3, PP-2 "Delta" was studied under various conditions of equilibrium between radon and products of its decay in the air. It was concluded that the efficiency of retention of radon decay products, occurring as radioactive aerosols, by the mentioned types of masks, comes to 75--87%. Anti-dust PM-1 (F-14 filter) and PM-3 (F-13 filter) masks are recommended as most efficient.

The ability of representative half-mask and single-use respirators with facial seal leaks to provide protection against aerosols was evaluated by experimental measurement. Respirators were mounted on a manikin in a test chamber and operated at seven steady flow rates over the range of 2 to 150 L/min. Samples of polydisperse and monodisperse aerosols were taken from inside and outside the respirator and analyzed by a calibrated optical particle counter over the particle-size range 0.1 to 11.3 microns. Measurements were made separately for filter performance as a function of particle size and flow rate, and simulated leak performance (penetration) as a function of particle size, pressure drop, and leak size. Flow rate vs. pressure drop measurements were made for all filters and leaks tested. For a given leak condition the percentage of the total flow traversing the leak varied several fold over the usual range of airflow rates through a respirator. Aerosol penetration was found to depend strongly on particle size and flow rate for filters, and to depend strongly on particle size and less strongly on pressure drop for leaks. One can conclude from these measurements that the aerosol-size distribution inside a respirator will nearly always be significantly different from that outside the respirator.

Sports-related eye injuries pose a substantial and preventable problem. Ophthalmologists, by educating their patients regarding the risks of eye injuries in various sports and the benefits availability of protective equipment, have the potential to prevent injury to well over 100,000 eyes each year. General guidelines and recommended levels of eye protection for various sports are given. The appendix lists suppliers of protective equipment.

Seven brands of bicycle helmets were compared by means of a drop test using an instrumented Hodgson-WSU headform, on the front (F), rear (R) and left side (LS) locations from a height of 1.0m and on the right front boss (RFB) from either 1.0m or 1.75m. Acceleration signals from the headform were computer processed to yield peak acceleration and the Gadd Severity Index (GSI). Significant differences between helmets and within helmets at different locations were found. Helmets with crushable polystyrene liners were much superior to those with soft foam liners. The superiority of the polystyrene liners disappeared however when helmets were subjected to two consecutive drops to the same location (R). The results also indicated that for most cases the GSI was between 800-1200 but there were two helmets that had values in excess of 1500. Clearly not all bicycle helmets provide equivalent levels of protection and some are much superior to others.

A new approach is presented to the problem of moisture chamber spectacles for the treatment of the dry eye. This moisture chamber relies on soft polyurethane sidewalls, form fitting and flanged to avoid pressure at right angles to the skin surface. The result is a comfortable moisture chamber which has been used successfully by an eight-year-old patient for nine months. This has allowed the child to return to school with best visual acuity (aphakic) without a single recurrence of corneal erosion.

Several types of respiratory protective hoods used by sandblasters were investigated in two steel fabrication yards. MSA Gravimetric Dust Samplers were used to collect respirable dust samples outside and inside hoods during sandblasting. Colorimetric and x-ray diffraction techniques were applied to the samples for free-silica determination. The majority of the sandblasters, who wore various types of air-supplied hoods, were exposed to an average level of silica dust several times higher than the TLV. Sandblasters wearing non-air-supplied hoods were at the greatest risk. Modern well maintained and properly worn air-supplied hoods offered fair protection during sandblasting periods, but the concentration of suspended respirable dust in ambient air during non-blasting intervals exceeded the TLV by several times.

In a consecutive series of 132 motorcycle and moped riders killed in 1977-1983 in southern Sweden and examined post mortem, almost half of the fatal injuries of the head and neck occurred remote from the point of impact, namely certain intracranial injuries without fractures, ring fractures of the base of the skull, disruption of the junction of the head and neck and injuries of the cervical spine. Ring fractures of the base of the skull were noticeably more frequent in motorcyclists than in car occupants who died. Injuries occurring remote from the point of impact were often the result of impacts against the anterior part of the head, especially against the face. All 5 riders suffering disruption of the junction of the head and neck were helmeted, which suggests that the helmet may promote such injuries. In some of these cases, no sign of impact against the head could be detected. The inertia of the head, enhanced by the helmet, is supposed to contribute to some of these injuries, which calls into question the protection provided by the helmet. Fatal head injuries at the point of impact were mostly found on the lateral-posterior part of the head. These injuries were often irrespective of whether or not a helmet was used. The points of impact were found mainly rung around the head. Protective helmets should be improved in order to give better protection against injuries at the site of impact, especially in the above-mentioned area, to give better protection of the face and to increase energy-absorbing capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Environmental emergency response teams are being established in local health departments throughout the country. A primary concern for these teams is personal protection from the hazardous materials at the response site. A set of guidelines is presented for establishing a personal protection plan for the environmental emergency response team which includes selection criteria for personal protective clothing and respirators as well as recommendations for ancillary components of the personal protection plan.

To arrive at transmittance standards for cold-weather goggles, the levels of natural radiation were estimated, and the amounts by which they must be reduced to fall below the damage thresholds for various bands of electromagnetic radiation were calculated. No more than 16% of UV from 320 to 40 nm, and no more than 5% of UV from 290 to 320 nm should be transmitted. If the short wavelengths of the visible spectrum (less than 500 nm) are filtered out, the remaining wavelengths appear to pose no danger. Measurements of the transmittances of a random selection of 13 commercial skigoggles showed that most offer satisfactory protection.

Infection related to clinical suction apparatus has been widely recognized. Safety systems available at present include devices to prevent overflow from collecting vessels and in-line air filters. The relative efficiency of these devices for the containment of aerosols generated within the collecting vessel has been evaluated. Although of increased resistance, filter capsules of 0.3-micron pore size prevented the passage of test aerosols for longer periods than the widely used 8-micron fibre filter tubes. Filter life can be prolonged by preventing overflow from collecting vessels and protecting against the passage of foam and froth.

This paper gives a comprehensive progress report on the development of objective methods for measuring the attenuation of hearing protection devices (HPD's), and focuses on the use of acoustic test fixtures (ATF's), i.e., artificial heads. While there are many publications on ATF's for the evaluation of circumaural HPD's (earmuffs), only one serious attempt to construct an ATF for the evaluation of intra-aural HPD's (earplugs) could be found. Consequently, no ATF for testing earplugs has been standardized so far, while two standardized ATF's currently exist for testing earmuffs [see ANSI S3.19-1974 (1975) and ISO/DIS 6290 (1983)]. Both ATF's are suited, however, only for production testing and are not designed for HPD-type testing. It is believed that both ATF's do not provide sufficiently high accuracy for HPD-type testing. A new ATF with appropriate circumaural and intra-aural flesh simulations was constructed, including a suitable ear simulator and a cast of an average pinna. Objectives for design and construction of the new ATF are discussed. The effect of using artificial flesh on the insertion loss of earmuffs (max. 5 dB at 125 and/or 250 Hz) and the effect of using a pinna (max. 12 dB lower insertion loss at 2 kHz) were evaluated.