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Biomedical subjects

G Marcaletti

Publications and source records attributed to G Marcaletti.

At least 19 recordsLinked to original sources
PubMed1989

[The evaluation of the individual thermal load in work activity with uneven energy expenditure].

It is often very difficult to quantify the potential thermal stress in jobs characterized by sudden variations of energy expenditure and thermal overload for time periods of short duration. Heart rate varies rapidly with the changes of energy expenditure and thermal load and the application of the mathematical model, proposed by Givoni and Goldmann for prediction of heart rate response to work in hot environments, to values of the physiological parameter, continuously measured during the periods of work and rest, allows the calculation of the two components of the HSI stress index (Er, Emax) from which to derive safe times of exposure. In this study practical applications of the theoretical method are verified in the control of the potential thermal stress of workers engaged in the carbon coke production. In that job the variability of thermal conditions make unfeasible a complete and whole evaluation of thermal overload only based on the measure of the microclimatic environmental parameters.

Coke↗
PubMed1988

[Assessment of risk in occupational tasks with exposure to environmental noise of variable duration and intensity].

The discontinuous exposure to environmental working noise often brings about risk situations hardly assessable by means of phonometric measurements and studying the exposure time, even if accurate. The use of the personal dosimetry can simplify the measurements and give a time-weighted value (Leq) comparable to a fixed limit value. Such a measurement is effective only for the considered time (usually a work shift); nevertheless it is assumed to be representative of the usual exposure to the job even though the variability of the working conditions constitute a limiting factor. In this work we tried to verify the possible use of the measurements of environmental sound pressure levels given by the dosimeter every 0.25 sec. The first aim being the study of the type of distribution of these values (during 5 consecutive shifts) and the estimate of mean and standard deviation values. The mean and the standard deviation values were used to get a OTL (one sided tolerance limits) usually employed for assessing the working chemical pollution. The second aim being the compliance control and the possible need of more measurements.

Environmental Monitoring↗
PubMed1984

[Prospects for environment intervention following biological monitoring of exposure to chromium].

The authors study the statistical distribution and the graphical representation of the urinary chromium values investigated during three consecutive years in three work environments of a same plant: polishing 1 degree, electrotyping, polishing 2 degrees, to evaluate the environmental situations of exposure and their variations. The adopted method, based on the graphical representation of the values in logarithmic coordinate paper, allows to quickly and carefully calculate the percent of the workers having urinary chromium values above the prefixed limits.

Chromium↗
PubMed1984

[Validity of a biophysical model for predicting heart rate values during activities operating under a risk of thermal stress].

After measuring the heart rate values of workers unfolding a standardized job made under unfavourable microclimatic conditions, the Authors calculate them by application of a proposed biophysical model starting from ambient climatic conditions, energetic expenditure and thermal resistance of the clothing. The results, compared by means of statistical methods, do not show any significant difference between the two methods. Therefore is also possible the proposal of the use of the biophysical model for the prevision of heart rate under standardized working conditions.

Heart Rate↗
PubMed1984

[Use of a biophysical model to verify various methods for limiting the time of work activity at risk in thermal stress].

The Authors measure the environmental microclimatic parameters (dry bulb temperature, wet bulb temperature, globe temperature, natural wet bulb, air speed, vapor pressure) in twenty working sites. Starting from the values obtained, they calculate the safe exposure times for works under unfavourable thermal conditions by means of three different methods (time weighted average WBGT, allowable exposure time-AET, required sweat rate index). Finally they verify the results obtained by application of a biophisical model proper to calculate the response of rectal temperature to changes in metabolic rate and environmental conditions.

Body Temperature↗
PubMed1984

[Control of duration limits of work activity at risk in thermal stress by prediction of values for internal body temperature].

A biophysical model for studying the response of the rectal temperature to changes in metabolic rate and environmental conditions has been utilized to establish the safe exposure times for works at risk of thermal stress. The prediction of the rectal temperature allows to evaluate for how long the heat load due to metabolic rate is lasting after the work stopping in the period of recovery.

Body Temperature↗
PubMed1984

[Decrease in environmental pollution and changes in biological indicators in occupational exposure to lead].

The Authors examine the variations of the levels of PbB and EPP in 39 workers at known lead exposure and evaluate the capacity of these parameters to follow the measured decreases of the environmental pollution. They conclude that the variations of the mean PbB values are well related to environmental pollution and that the diagram on the probability paper of median values and their corresponding standard deviations allows to calculate the number of exposed workers with biological values above a fixed limit.

Adult↗
PubMed1984

[Microclimatic indexes and limits of safe exposure in work activity at risk of thermal stress].

The working time in work places thermically uncomfortable must be limited in order to prevent the risk of thermal stress. In a previous study we have demonstrated that the best method for calculation of the safe exposure times is based on the required sweat rate index. In the present work we verified in different work places termically uncomfortable, grouped for equivalent values of WBGT index, the variability of the safe exposure times calculated by means of a method just now mentioned for various levels of energetic expenditure. The results point out the possibility of a mathematical relation between energetic expenditure, WBGT index and mean of safe exposure times.

Climate↗
PubMed1984

[Control of cardiac frequency in work activity at risk of thermal stress].

The working time in work places termically uncomfortable must be limited in order to prevent the risk of thermal stress; the safe exposure times are based on the microclimatic parameters and the energetic expenditure required for the job. Hearth rate measure is proposed by various Authors as index connected with the energetic expenditure level and with the microclimatic conditions. In the present work the Authors realise the monitoring of a job uncomfortable for thermal conditions by means of the hearth rate measure of the workers. The results show the better accuracy of the purposed method in comparison with the application of the safe exposure times.

Heart Rate↗
PubMed1984

[Thermal balance in workers of in greenhouses for the cultivation of tropical plants].

The Authors starting from the microclimatic parameters globe temperature (tg), dry bulb temperature (ts) forced wet bulb temperature (tu), natural wet bulb temperature (tun), speed of the air (v) observed every half an hour in greenhouses for tropical plants, evaluate the required sweating rate per hour during a specimen working shift for a known energetic expenditure. The sweating rate values calculated exceed by far the highest limits accepted for the workers perfectly acclimatized and impose the application of the working safe exposure times.

Agriculture↗
PubMed1983

[Microclimate and duration of work tolerance in hothouse for cultivation of tropical plants].

The AA. starting from the environmental values carried out in a greenhouse for tropical plants investigate the possibility of prevent the risk of thermal stress at standardized energetic expenditures by means of the measurement of a few microclimatic parameters; they elaborate also a nomogram proper to calculate the safe exposure times for works under unfavourable thermal conditions.

Climate↗
PubMedDate not supplied

[Evaluation of thermal comfort in a student population: predictive value of an integrated index (Fanger's predicted mean value].

Practical applications and predictive values of a thermal comfort index (Fanger's PRV) were verified on a sample school population (1236 subjects) by studying the relationships between thermal sensations (subjective analysis), determined by means of an individual questionnaire, and the values of thermal comfort index (objective analysis) obtained by calculating the PMV index individually in the subjects under study. In homogeneous conditions of metabolic expenditure rate and thermal impedence from clothing, significant differences were found between the two kinds of analyses. At 22 degrees C mean radiant and operative temperature, the PMV values averaged 0 and the percentage of subjects who experienced thermal comfort did not exceed 60%. The high level of subjects who were dissatisfied with their environmental thermal conditions confirms the doubts regarding the use of the PMV index as a predictive indicator of thermal comfort, especially considering that the negative answers were not homogeneous nor attributable to the small thermal fluctuations (less than 0.5 degree C) measured in the classrooms.

Adolescent↗
PubMedDate not supplied

[Evaluation of individual thermal load in working environments with non-homogeneous microclimatic conditions].

It is often very difficult to quantify the potential thermal stress of jobs requiring high worker mobility in unevenly hot environments. The determination of integrated indexes such as HSI can be a cause of error in risk evaluation. However, monitoring of physiological parameters of exposed workers, such as internal body temperature, provides a direct expression of man-environment interaction. On the basis of measurement of micro-climatic parameters and internal body temperature of subjects employed in a glass production plant, an attempt was made to calculate an integrated index of thermal stress risk which reflected the job requirements. The mathematical model used was the one proposed by Givoni and Goldman for prediction of rectal temperature and heart rate response to work in hot environments.

Body Temperature↗