CEN Standards for Testing and Certifying Personal Protective Equipment-Status Quo and Deficiencies: Examples Kurt Jung, 108-117 The Subjective Rating Scales for Measurement of Mental Workload- Thurstonian Scaling Bohdan Dudek, Jerzy Koniarek, 118-129 Mental Workload and Health: A Latent Threat Tatiana Klonowicz, 130-135 Workplace Design for Manual Assembly Tasks: Effect of Spatial Arrangement on Workcycle Time Kamal P. Kothiyal, B. Kayis, 136-143 Assessment of Physical Load at Worksites: A Finnish-German Concept Veikko Louhevaara, 144-152 Most Comfortable Listening Level and Speech Attenuation by Hearing Protectors Tomasz Letowski, Donna M. Magistro, Amy C. Ritter, 153-159 Flicker Test as a Load Measurement During the Combined Effect of Heat and Noise Anna Łuczak, Bożena Kurkus-Rozowska, Andrzej Sobolewski, 160-166 Chlorfenvinphos Dermal Absorption in Rats. Histological and Ultrastructural Changes in the Skin and Internal Organs Sabina Toś -Luty, Janina Halliop, Jadwiga Latuszyńska, Maciej Latalski, Alina Tochman, Daniela Obuchowska, 167-178 The European Conformity Assessment Procedures and the Quality Assurance Instruments for Personal Protective Equipment in the Internal Market Joachim Lambert, 179-184 A Digital Filter for the State Estimation of Impulsive Noise under the Existence of a Background Noise and Its Experiment in the Work Environment Akira Ikuta, Mitsuo Ohta, 185-192 Arm and Leg Girths of Industrial Workers During a Workday Űlo Kristjuhan, 193-198

CEN Standards for Testing and Certifying Personal Protective Equipment-Status Quo and Deficiencies: Examples
Kurt Jung, 108-117

By establishing the internal market, the European Union intended to create an area in which safety and health at work are guaranteed. For this purpose, a series of directives was passed.
The EC Directive 89/686/EEC "Approximation of the laws of the Member States relating to personal protective equipment" is of particular interest to the manufacturers of personal protective equipment (PPE). On the European level, harmonized standards, that put these basic health and safety requirements into more concrete terms have to be available. The European Standardizing Committee (CEN) is charged with the elaboration of European standards.
A total of 176 standards relating to personal protective equipment have to be set up; 57 of them are available at present. All CEN members are obliged to transpose them without modification into national standards. Formerly existing national standards have to be withdrawn.
Existing European standards sometimes show deficiencies regarding the specification of requirements according to Directive 89/686/EEC: the standardization of PPE for special fields of application and insufficient harmonization of provisions for different PPE serving the same protective purpose. Test methods are not always described precisely enough.

The Subjective Rating Scales for Measurement of Mental Workload-Thurstonian Scaling
Bohdan Dudek, Jerzy Koniarek, 118-129

Subjective rating scales for measuring work demands and individual capabilities to cope with work requirements were developed using the Thurstonian procedure. Scales for measuring six dimensions of mental workload: mental difficulties, feeling of responsibility, awareness of risk, interpersonal conflicts, monotony and time pressure were prepared. Individual scale results make it possible to assess the level of mental workload understood as a relation between the subjective rating of work demands and individual capabilities in each of the six dimensions. Two versions of scales were prepared: classic and modified ones. To assess the level of reliability of the particular scales, 481 subjects were examined twice with a one month interval. A procedure enabling the preparation of scales for the measurement of other than the six above-mentioned dimensions of mental workload was presented.

Mental Workload and Health: A Latent Threat
Tatiana Klonowicz, 130-135

The aim of this study is to investigate changes in cardiovascular activity associated with a high mental workload. The reported experiments, carried out in naturalistic settings, point to information load and information processing under time pressure as main risk factors. This kind of occupational stress had to be dealt with by two of the three -- groups under investigation: brokers and simultaneous interpreters. It was not experienced by lecturing university professors. The pattern of cardiovascular activity of the two former groups consisted of over-mobilization of cardiovascular activity, at the beginning of work, and only partial normalization of task-evoked changes in cardiovascular activity at the end of work. Substantial elevations of diastolic blood pressure and tachycardia, which followed earlier over-mobilization, resemble a miniature of changes seen in the development of cardiovascular diseases.

Workplace Design for Manual Assembly Tasks: Effect of Spatial Arrangement on Work-Cycle Time
Kamal P. Kothiyal, Berman Kayis, 136-143

This article reports the results of an experimental study undertaken to investigate the effect on work-cycle time of spatial arrangement of assembly board and parts bin in the normal work area in manual assembly tasks. Operator performance was measured in terms of average work-cycle time taken to complete a laboratory simulated manual assembly task. Results showed that both location and distance factors had significant effects on work-cycle time. Effect of the size of parts was also investigated in the study. Average observed work-cycle times were compared with the methods-time measurement (MTM) values. Repetitive manual assembly tasks are common in industry and are thought to lead to musculoskeletal disorders. The results of this research are important for ergonomic design of the workplace for assembly tasks, which would help to enhance operators' efficiency.

Assessment of Physical Load at Work Sites: A Finnish-German Concept
Veikko Louhevaara, 144-152

The aim of this paper is to introduce a set of methods of work physiology for the assessment of physical load at the worksite, and to consider (1) their relevance for different types of muscular work, and (2) their feasibility for occupational health and safety practitioners. The results of an ergonomic intervention study for the reduction of work load associated with various manual materials-handling tasks were used for the evaluation of the feasibility and sensitivity of the measurements of heart rate, the Edholm and OWAS methods as well as the ratings of overall and local perceived exertion. The methods proved feasible, although time-consuming, and their sensitivity for the quantification of small changes in physical work load was limited. Despite these shortcomings those methods can be used by occupational health and safety practitioners when their strategy and data collection techniques are developed further. In conclusion, there are relevant and feasible methods for a reliable worksite assessment of cardiorespiratory and postural load related to the activation of large muscle masses. On the other hand, field methods for the quantification of local static work load and repetitive type of work load with small muscle masses are scarce.

Most Comfortable Listening Level and Speech Attenuation by Hearing Protectors
Tomasz Letowski, Donna M. Magistro, Amy C. Ritter, 153-159

Hearing protectors attenuate both the background noise and the useful sounds embedded in noise such as the sounds of speech and warning signals. An effective hearing protector is that one which attenuates background noise while leaving sufficient energy of speech and warning signals reaching the ear of the worker. At present, however, there are no established criteria for assessing effective change in speech-to-noise ratio caused by hearing protection devices (HPDs). One such criterion could be a change in most comfortable (listening) level (MCL) for speech caused by the presence of HPDs. In the present study the HPD-related shift in MCL for speech presented in quiet was measured and compared with two measures of noise attenuation: NRR and H-M-L. The results indicate that MCL shift may be a sensitive measure of speech attenuation by HPDs that together with the appropriate H-M-L may describe technical properties of HPDs.

Flicker Test as a Load Measurement During the Combined Effect of Heat and Noise
Anna Łuczak, Bożena Kurkus-Rozowska, Andrzej Sobolewski, 160-166

This study was a joint physiological and psychological experiment undertaken in order to determine changes in physiological and psychological human functions under the combined influence of heat, noise and physical activity.
Seven experimental situations were simulated in a climatic chamber, with different configurations of three independent variables: heat (40°C), noise (98 dB) and physical effort (30% V02 max).
Five psychological variables (CFF, hand tremor, reaction time, subjective climate evaluation and subjective evaluation of the given condition load) and two physiological variables (heart rate and rectal temperature) were monitored.
Results indicate that CFF changed (increased) significantly when more than one experimental variable was applied. These changes coincided with significant changes in both subjective climate evaluation and subjective evaluation of a given condition load. There were no significant changes in psychomotor functions (hand tremor and reaction time).
None of the observed physiological parameters were above the critical value.
The results obtained let us suggest that CFF can be treated as a psychophysical load indicator.

Chlorfenvinphos Dermal Absorption in Rats. Histological and Ultrastructural Changes in the Skin and Internal Organs
Sabina Toś -Luty, Janina Halliop, Jadwiga Latuszyńska, Maciej Latalski, Alina Tochman, Daniela Obuchowska, 167-178

We studied the effect of chlorfenvinphos dermal absorption on the morphological picture of blood, on the histological and fine structure of tail skin, as well as on the histological structure of internal organs (lungs, heart, liver, spleen, kidney) of rats.
The study was conducted on 25 white Wistar strain rats, the tail skin of which was -- or was not -- hydrated before the exposure. Rat tails were soaked in 0.5% or 0.05% chlorfenvinphos for one hour a day for three months. Evident tendencies for a decrease in the absolute level of leukocytes and for an increase in the absolute level of erythrocytes in all experimental animals were observed. Histopathological changes in the internal organs were mildly manifested in only a few rats, mainly as liver and pulmonary hyperaemia. Rat tail skin at the direct exposure site showed hyperceratosis, intensive desquamation, and compensatory hyperplasia.

The European Conformity Assessment Procedures and the Quality Assurance Instruments for Personal Protective Equipment in the Internal Market
Joachim Lambert, 179-184

Conformity assessment procedures prescribed by European legislation are presented and their concrete implementation is illustrated by the example of personal protective equipment. The different categories of personal protective equipment defined by the Directive 89/686/EEC are explained, with reference to the applying conformity assessment elements. Quality assurance of production is presented as being the central element of the conformity assessment procedure for complex personal protective equipment. Special emphasis is put on the necessity of having a regular exchange of views and information between notified bodies in Europe. Ways in which third countries can eventually carry out conformity assessment on the basis of a contract with the European Community Commission are explained.

A Digital Filter for the State Estimation of Impulsive Noise under the Existence of a Background Noise and its Experiment in the Work Environment
Akira Ikuta, Mitsuo Ohta, 185-192

In the actual work environment, a specific objective noise like machine and industrial noises shows impulsive fluctuation form. Furthermore, it often occurs that a specific noise is partially or completely contaminated by the background noise. In that case, the fluctuation wave form of the specific noise has to be estimated moment by moment in order to evaluate and/or improve the work environment. In this study, a digital filter for estimating an impulsively fluctuating specific noise is proposed. More specifically, after introducing a generalized time series regressive model of the specific noise, a method for estimating the impulsive noise based on an observation contaminated by the background noise is theoretically derived. Furthermore, the proposed method is applied to the actual task of estimating an industrial impact noise.

Arm and Leg Girths of Industrial Workers During a Workday
Űlo Kristjuhan, 193-198

The aim of this study was to characterize changes in the limb perimeters of workers in various widespread occupations in Estonian industry. Investigations were carried out using special measuring instruments designed in Tallinn Technical University. The subjects under investigation consisted of 202 workers: garment workers, tailoring cutters, shoe factory operators, weavers, press operators, fitters, drivers.
Investigations in the workshops showed that during the initial part of a work-shift perimeters often decreased. By the end of the shift, girths increased markedly (up to 1.6%), depending on the properties of the external load. There are many reasons for this change, with fatigue often playing an important role.
The exact measurement of the girths of human limbs is of great importance for collecting information in the field of ergonomics. It is possible to find effective preventive measures against fatigue and occupational diseases.