Biomedical subjects

A Vitalis

Publications and source records attributed to A Vitalis.

4 recordsLinked to original sources

PubMed2002

The effect on heart rate and facial skin temperature of wearing respiratory protection at work.

Twelve New Zealand workers from a range of occupations were studied to investigate the effect of wearing air-filtering respiratory protection on heart rate (HR) and facial skin temperature (Tlip and Tcheek) whilst working. All variables were measured continuously during simulated and actual work. The former allowed physiological measurements to be undertaken during the physical activities carried out during the work task without respirators and without exposure to hazardous airborne substances. Mean heart rates in subjects moving without respirators ranged from 75 to 94 beats/min and from 77 to 98 beats/min during respirator use at work. Mean skin temperature under the mask (Tlip) increased in 11 of the 12 subjects while using respirators (range 1.2-4.8 degrees C) but Tcheek only increased in four (range 0.6-1.5 degrees C). The use of simulated work tasks in the experiment was a compromise. The heart rate data from the real and simulated work indicated that effort and workload, though not identical, were similar. The increase in skin temperature under the mask may account for the reluctance of individuals to wear respiratory protection at work. This region of the face is very thermosensitive.

Adult↗

PubMed2001

Unfocused ergonomics?

Ergonomics is now fairly routinely used in industry. Managers often initiate contact with ergonomists. The paper argues that many ergonomists have abandoned some fundamental ergonomics principles and have unwittingly succumbed to 'sitting complacently in the manager's toolbox'. It is also argued that through its inherent diversity, ergonomics is in danger of becoming fragmented and losing its identity.

Ergonomics↗

PubMed1995

Predicting heart rate response to various metabolic rates, environments, and clothing.

A mathematical model that describes heart rate (HR) responses to different combinations of metabolic levels, climatic conditions, and clothing ensembles was developed. The database that served to construct the model consisted of 48 variations representing a wide range of environmental conditions, clothing ensembles, and metabolic rates. The model, which correlates highly with the observed values (r = 0.88, P < 0.0001), is based on physiological and environmental parameters: HR = 57.1 + 0.6HRi + [0.07M - 19.06 - 0.011(Emax - Ereq)] log t, where HRi is initial HR in beats per minute (at rest before the exposure), t is the time of exposure in minutes, M is the metabolic rate in watts, Ereq is the required sweat evaporation for thermal equilibrium in watts, and Emax is the maximal evaporative capacity of the environment in watts. The model's validity was tested by using two independent databases representing wide ranges of conditions; the correlation between measured and predicted values was found to be highly significant (r = 0.83, P < 0.001 and r = 0.77, P < 0.001, respectively). In summary, the present study suggests a valid predictive model for HR that overcomes some of the difficulties observed in other models.

Adult↗

PubMed1994

Heart rate strain indices in Greek steelworkers.

The heart rate strain of 14 Greek steelworkers was assessed during the winter and summer months of 1989 and 1990. Activity sampling was used to establish the pattern of work performed and heart rates were measured throughout work shifts. In addition, maximum aerobic capacity was estimated. The mean heart rate during work was 97 bt.min-1 (+/- 13), while the mean relative heart rate increase was 21% (+/- 15%). The results indicated that the work performed could be classified as light to moderate.

Adult↗