Validity of the 1984 Interim Guidelines on Airborne Ultrasound and Gaps in the Current Knowledge.

ABSTRACT: Airborne ultrasound is used for various purposes both in industrial and public settings, as well as being produced as a by-product by a range of sources. The International Radiation Protection Association (IRPA) published interim guidelines on limiting human exposure to airborne ultrasound in 1984, based on the limited scientific evidence that was available at that time. In order to investigate whether research since 1984 requires the development of revised exposure guidelines we considered (a) within the context of ultrasound exposure the relevance to health of the biological endpoints/mechanisms listed in the IRPA guidelines, (b) the validity of the exposure limits, and (c) whether there are biological endpoints/mechanisms not covered in the guidelines. The analysis of the available evidence showed that the biological endpoints that form the basis of the guidelines are relevant to health and the guidelines provide limits of exposure based on the evidence that was available at the time. However, the IRPA limits and their associated dosimetry were based on limited evidence, which may not be considered as scientifically substantiated. Further, there is no substantiated evidence of biological endpoints/mechanisms not covered by the IRPA guidelines. These two observations could mean that IRPA's limits are too low or too high. Research since the IRPA guidelines has made some improvements in the knowledge base, but there are still significant data gaps that need to be resolved before a formal revision of the guidelines can be made by ICNIRP, including research needs related to health outcomes and improved dosimetry. This statement makes a number of recommendations for future research on airborne ultrasound.

Assessment of working conditions in medical facilities due to noise.

Factors related to the working environment (e.g. inadequate lighting, excessive noise, poor condition of premises) contribute to neglect in the work of medical personnel, while also causing health effects in their body. This article presents the results of the assessment of working conditions in workplaces at selected medical facilities in Poland. This assessment was based on survey results. The survey was conducted by means of a questionnaire among more than 300 physicians, nurses and diagnostic laboratory staff. The average grading of noise annoyance in workplaces on a scale from 0 to 10 was 2.77, and therefore noise was assessed as a slight inconvenience.

Effects of Tonal Noise on Workers' Annoyance and Performance.

OBJECTIVE: Numerous references indicate that the subjectively assessed tonal noise annoyance is higher than that of broadband noise. There are no criteria for the impact of tonal noise in assessing the occupational environment for both indoor areas and workplaces. MATERIALS AND METHODS: The study participants included 50 people who met the audiometric qualification criteria. The research method employed both a questionnaire survey and computer psychological tests checking work performance, attention level, and memory. Four types of generated test signals were developed (filtered noise - A and three signals with tonal components 125, 1600, and 8000 Hz - B, C, and D) at the same sound level A of 55 dB. Test signals C and D were assessed as causing the greatest annoyance and as the loudest. RESULTS: The results of some tests and the assessment of annoyance and of the volume of test signals containing medium and high frequency tonal components were correlated with the participants' noise sensitivity, determined on the basis of a questionnaire. Although there are no statistically significant differences, it was observed in most cases for signals with C (1600 Hz) and D (8000 Hz) tonal components that the results (mean values or median values) of psychological tests deteriorated with respect to a noise signal without tonal components (A) - a smaller number of calculations, a smaller number of correct responses, more errors made. CONCLUSION: These results, combined with those of the questionnaire survey, justify the introduction of the tonality annoyance criterion for workstations where, among other things, focusing one's attention is required.

Ultrasonic noise measurements in the work environment.

In many countries, ultrasonic noise is included in the list of factors harmful to health in the work environment. For the frequency range above 20 kHz, there is no clear and complete information on the factors influencing the result of a measurement of sound pressure level. Moreover, there are no current international standards for performing measurements of ultrasonic noise at work stations. This article presents a possibility for the adaptation of the existing measurement methods [e.g., ISO 9612:2009 (2009)] to the ultrasonic range. In particular, it discusses the requirements for measuring instruments, procedures to be followed while performing measurements, the application of a correction to measurement results, and the determination of measurement uncertainty. The development of a consistent method of ultrasonic noise measurement is of utmost importance in carrying out an assessment and reducing the risk of exposure to this physical factor in the work environment.

[Influence of classrooms acoustics on the teachers' voice sound pressure level]. / Wplyw wlasciwosci akustycznych sal lekcyjnych na poziom cisnienia akustycznego mowy nauczycieli.

BACKGROUND: Despite recent decreases in the number of registered cases of chronic disease of vocal mechanism, this disorder is still at the forefront of all occupational diseases in Poland. Most of the cases are observed in the Section of Education. Acoustic conditions in classrooms are often thought to be one of the causes of voice disorders. The aim of this study was to examine how the acoustics of classrooms affects the sound pressure of teachers' voice. MATERIAL AND METHODS: The acoustic properties of 21 classrooms in primary schools were studied as regards the working conditions of teachers' voice. The classrooms were divided into two groups: classes 0-III and classes IV-VI. Measurements of acoustic properties were performed according to PN-EN ISO 3382-1:2009, and measurements of sound pressure levels in the classrooms according to the Hodgson method. To study the relationship between the variables Spearman's rank correlation analysis was used. RESULTS: The study revealed a statistically significant relationship between the classroom acoustics and the students' activity (correlation coefficient, 0.86). It was also shown that the students' activity directly affected the level of teachers' voice (correlation coefficient, 0.68). In only 24% of classrooms SPL of teachers' voice corresponded with the level of normal speech. CONCLUSIONS: The SPL of teachers' voice is influenced by a number of factors, including background noise and indirectly the classroom acoustics. One of the possibilities to improve working conditions of teachers is to create a suitable acoustic climate in the workplace, through acoustic treatment or changing equipment.

[Noise-induced risks at workstations in Poland and other European Union countries]. / Zagrozenia halasem na stanowiskach pracy w Polsce i innych panstwach Unii Europejskiej.

Noise is one of the most common physical risks in the workplace. Long term exposure to its high levels (above 80-85 dB) can pose a significant threat to health of workers, including hearing loss. Noise can also be a burdensome factor hampering work, causing stress and various health problems. In the European Union about 80 million workers (1/3 of total working population) complain about noise. In Poland, there are about 200 thousand workers exposed to noise in excess of MAI values. For years noise-induced hearing loss has been at the top of the list of occupational diseases. This paper presents a review of the data on noise hazards in the EU countries based on the reports of the European Foundation for the Improvement of Living and Working Conditions and publications of the European Agency for Safety and Health at Work. The statistical data on working conditions in Poland (including noise-induced risks) obtained from the Central Statistical Office and statistical data on occupational diseases (including hearing loss) elaborated by the Nofer Institute of Occupational Medicine in Lódz were the subject of analysis. The article also presents the results of noise measurements and surveys carried out in selected national companies. The obtained results indicate the necessity for both objective and subjective assessments of noise hazards in the workplace.