PubMed Health⌕ Search

Biomedical subjects

P Mairiaux

Publications and source records attributed to P Mairiaux.

16 recordsLinked to original sources
PubMed2003

A structured strategy for assessing chemical risks, suitable for small and medium-sized enterprises.

BACKGROUND: A previous study carried out in 20 Belgian companies, especially small and medium-sized enterprises (SMEs), showed that prevention advisors did not use any structured approaches to assess chemical risk. They used their personal judgement and the information contained in manufacturers' Safety Data Sheets to assess the risk. OBJECTIVE AND METHOD: The purpose of the Regetox network is to provide companies with a global approach for assessing chemical health risks. The structured approach proposed consists of two successive steps of increasing complexity. For the first step, we chose a method developed by the INRS (France), the 'ranking of potential risk', which allows the safety officer or staff member to identify hazards and to set priorities among all the supplied products used in the workplace. For the second step, we applied the COSHH method and EASE model established by the UK Health & Safety Executive for assessing 'chemical risk by reference to occupational exposure limits'. The INRS and COSHH Essentials methods were chosen because they define hazards using R-phrases of the European classification system and assess the exposure by using simple information that is easy to collect in the workplace and toxicological databases. A feasibility study conducted in two enterprises shows the usefulness of this approach. In addition to the intrinsic limitations of the methods, the approach showed some limitations related to the inaccuracy of the manufactured safety data sheets and to the collection of the basic information needed for ranking potential risks. CONCLUSION: The use of the Regetox approach needs training of prevention advisors and a strategy involving employers, staff members and workers in collecting basic information and managing chemical risks. Under these conditions, Regetox seems to be a useful tool for chemical risk assessment in SMEs.

Belgium↗
PubMed1991

Strategy of analysis and interpretation of thermal working conditions.

This paper proposes a strategy for the management of heat problems at the workplace. This includes three steps of analysis: the first aims at recognizing the problem and classifying it under one of the categories--comfort, discomfort but no health risk, or health risk either in the long term or in the short term. The second is designed to evaluate the magnitude of the problem and to optimize the choice of solutions. The interpretation of the data is based on analytical indices: the PMV-PPD indices for heat discomfort conditions and the Required Sweat Rate index for heat stress conditions. The third step involves an in-depth analysis of the situation: this will be undertaken only if a major problem of heat stress has been detected at the previous stage and providing technical solutions cannot be immediately implemented. The advantages and possible limitations of this step-by-step approach are outlined and its cost effectiveness is discussed in the perspective of a true management of health and safety at work.

Adult↗
PubMed1988

Reproducibility of intra-abdominal pressure when lifting.

Reproducibility of intra-abdominal pressure (IAP) variation was investigated in fifteen young male subjects when lifting three loads, 49, 98 and 147 N, with three speeds of movement, slow, fast and spontaneous, and starting from four standing postures: trunk erect, trunk forward flexed at 30, 60, and 90 degrees of dorsolumbar inclination. Each lift was replicated five times successively and the whole protocol was replicated at one a week interval. The intra-individual variability in IAP response was assessed using the standard deviation of each series of ten lifts. Results showed that variability of peak IAP increased with the load and with the lifting speed. This effect of speed was especially observed for light loads and in forward bending postures. Trunk posture had in itself no significant effect on IAP reproducibility. However, when the variations in the moment acting at lumbar level were taken into account by considering the IAP to moment ratio, the reproducibility of the response was not affected by the load but only by the trunk posture. Reproducibility was lower in the erect posture than in the three flexed positions. It is suggested that this difference relates to the importance in each posture of the moment acting at the shoulder with respect to the total moment acting at lumbar level.

Abdomen↗
PubMed1987

Prediction of mean skin temperature in warm environments.

The data collected by the authors in four experimental series have been analysed together with data from the literature, to study the relationship between mean skin temperature and climatic parameters, subject metabolic rate and clothing insulation. The subjects involved in the various studies were young male subjects, unacclimatized to heat. The range of conditions examined involved mean skin temperatures between 33 degrees C and 38 degrees C, air temperatures (Ta) between 23 degrees C and 50 degrees C, ambient water vapour pressures (Pa) between 1 and 4.8 kPa, air velocities (Va) between 0.2 and 0.9 m.s-1, metabolic rates (M) between 50 and 270 W.m-2, and Clo values between 0.1 and 0.6. In 95% of the data, mean radiant temperature was within +/- 3 degrees C of air temperature. Based on 190 data averaged over individual values, the following equation was derived by a multiple linear regression technique: Tsk = 30.0 + 0.138 Ta + 0.254 Pa-0.57 Va + 1.28.10(-3) M-0.553 Clo. This equation was used to predict mean skin temperature from 629 individual data. The difference between observed and predicted values was within +/- 0.6 degrees C in 70% of the cases and within +/- 1 degrees C in 90% of the cases. It is concluded that the proposed formula may be used to predict mean skin temperature with satisfactory accuracy in nude to lightly clad subjects exposed to warm ambient conditions with no significant radiant heat load.

Adult↗
PubMed1987

Physiological factors associated with the onset of sweating.

The influence of esophageal (Tes) and skin temperature (Tsk) variations, body heat storage, and individual parameters on the initiation of sweating was investigated in 9 unacclimated subjects during thermal transients induced by exercise (25, 50, or 75 W) and by a step change in ambient temperature from 28 degrees C to 23, 28, 36.5, 45, or 50 degrees C. Seventy-four onsets of sweating were observed during the exposures, the sweating delay averaging 3 min at 45 and 50 degrees C, 6 min at 36.5 degrees C, and 9.5 min at 28 degrees C. In warm conditions (36.5 to 50 degrees C), the onset of sweating could mainly be related both to the level of Tsk and its rate component, whereas in cooler conditions (28 and 23 degrees C), the onset of sweating could only be related to a positive rate of Tes variation, the Tsk level being low and steady. On the whole set of data, the Tes changes at the onset were inversely related to the Tsk changes. The cumulated heat storage at the onset of sweating was 37 kJ/m2 (S.D. 25). It varied not only among subjects (range: 11-66 kJ/m2) but also within subjects even when differences in thermal state prior to exercise were accounted for. Among the individual parameters investigated, the magnitude of the decrease in Tes observed in response to the start of exercise was found to have a significant effect on the sweating delay. The Tes decrease was inversely related to the subject's skinfold thickness, and in a given subject, inversely related to the preexercise Tsk. It is concluded that the results are in agreement with a summation model of internal and mean skin temperatures on the sweating drive but that they do not verify the hypothesis of a critical level of heat storage at the onset of sweating.

Body Temperature↗
PubMed1986

Serum creatine kinase relationship to postural constraints in manual work.

Serum creatine kinase (CK) variations during work and subjective assessments of postural discomfort were analysed in 30 workers assigned to three different tasks in a rolling mill. After four days of work, serum CK levels were significantly increased above control levels. No difference was found between the tasks studied. Inter-individual variability in CK response was large: a marked CK increase was only seen in 21 workers, while 5 workers showed a marked CK decrease. The postural discomfort sensations increased with work in each group, with their location in the body being related to the characteristics of each task or workplace. No relationship was found between the postural discomfort scores and CK changes. Results showed that determination of an individual baseline CK level was difficult to achieve in an occupational setting. It is concluded that CK variations cannot reliably be used in the field for detection of individuals exposed to excessive postural constraints. Their use as a screening tool in groups of workers assigned to similar tasks deserves further study.

Adult↗
PubMed1985

Workers self-pacing in hot conditions: a case study.

It is not always possible in hot environments, to determine safe work-rest regimens based upon heat stress criteria. Is it then a good health policy to rely upon the self-pacing of the workers? To address this question, we observed the spontaneous work-rest cycles of seven masonry workers allocated to the maintenance of a float-glass furnace and the workers' heart rate and rectal temperature were continuously monitored. Results showed that the regimens adopted by the workers were poorly related to physiological parameters. The duration of each heat exposure was significantly related to the worker aerobic capacity, but not to the heart rate level reached at the end of the working period. Due to self-pacing of the task, heart rates and rectal temperatures remained within acceptable limits for all workers but one, even though these workers were rather old and had a rather low physical capacity. These favourable results may be ascribed to a spontaneous limitation of the effective working time to about 25% of the shift duration and to the fact that subjects worked, in pairs alternately, to perform the task. It is concluded that self-regulation of the work-rest cycles can be an effective means to protect the workers exposed to hot conditions from an excessive physiological strain, providing that the task has no urgent character and does not involve productivity incentives, and that the workers are well trained to their job.

Journal Article↗
PubMed1983

Oral temperature as an index of core temperature during heat transients.

Rectal (Tre), oral (Tor) and oesophageal (Tes) temperatures were measured in five exercising subjects exposed for two hours to five conditions (1) a steady condition (WR) involving a constant work load (50 W) at a constant air temperature (Ta = 36.5 degrees C); (2) air temperature variations (delta Ta) between 28 degrees C and 45 degrees C and (3) between 23 degrees C and 50 degrees C at constant work load (50 W); (4) and (5) to work load variations (delta W) between 25 W and 75 W at a constant Ta (= 36.5 degrees C). Oral temperature recordings were taken sublingually and were either continuous or discontinuous. When discontinuous, the time needed for Tor to stabilize after the mouth opening was taken into account. The respective reliability of Tor and Tre as estimates of Tes were compared in each condition. Results showed that the resting (Tor - Tes) difference (+ 0.12 degrees C) was barely modified after two hours of exposure, whereas Tre overestimated Tes by 0.2 degrees C to 0.4 degrees C depending on the condition. The Tor variations were highly correlated with Tes variations under steady condition and under air temperature variations. In these conditions, Tor represented the best estimate of Tes. Under work-load variations, Tor was less closely related to Tes than was Tre. It is suggested that the relative inertia of Tor to step changes in exercise intensity could be ascribed to work induced variations in mouth blood flow.

Adult↗
PubMed1982

Central and peripheral inputs in sweating regulation during thermal transients.

Eight nude resting men were exposed to consecutive heating-cooling cycles of air and wall temperatures varying from 28 to 45 degrees C in a sawtooth pattern using one of the following slopes: +/- 3.40, +/- 2.27, +/- 1.70, +/- 1.42, or +/- 1.13 degrees C . min-1. Ambient vapor pressure and air velocity were kept constant at 20.0 mbar and 0.9 m . s-1, respectively. Continuous measurements were made of rectal, esophageal, and mean skin temperatures. Local upper limb sweating response was measured from an arm chamber under a local thermal clamp. The results point out the insufficiency of an explantation based on a simple additive function of core and skin temperatures for describing the sweating regulation. During transient thermal loads, a multiplicative interaction of mean skin and core temperatures must also be taken into account for describing the central drive for local sweating response. The interindividual differences observed in the sweating regulation mechanism seem to be linked to a nonlinearity in the response of the thermoregulatory system.

Adult↗
PubMed1977

[Evaluation of the effects of cooling clothes on the adaptation to prolonged exertion in high temperatures by miners].

In order to improve the working conditions of coalminers exposed to high ambient temperature, the authors have studied the effects of wearing an under-vest and a cowl covering the head and shoulders made in sponge-cloth and soaked with cold water (cooling clothes). Eight coalminers volunteered for this study which included three sessions of prolonged intermittent exercise performed in a climatic room with the following ambient temperatures:--experiment A (comfortable environment): td = 28 degrees C; twb = 20 degrees C; bare head and bare torso;--experiment B (hot environment) :td = 38 degrees C; twb = 30 degrees C; bare head and bare torso;--experiment C (hot environment and cooling clothes) : td = 38 degrees C; twb = 30 degrees C; wet undervest and cowl soaked with cold water (16 degrees C) every 15 minutes. Each experiment included 5 periods of exercise each lasting 15 minutes separated by periods of rest lasting 15 minutes; the exercises were performed on a bicycle ergometer or on a treadmill and their intensity corresponded to 50% of the maximal oxygen intake. In the comfortable environment (experiment A), all subjects completed the experiment without undue fatigue; the final heart rate was 81/min and the final rectal temperature was 37.6 degrees C; the weight loss never exceeded 1 Kg. In the hot environment (experiment B), all subjects were exhausted at the end of the study which had to be shortened in 2 cases. The final heart rate was 125/min and the final rectal temperature 38.8 degrees C; the weight loss was above 2 Kg. The use of the "cooling clothes" in the hot environment (experiment C) resulted in significantly (p less than 0.001) lower heart rate (104/min), rectal temperature (38.3 degrees C) and weight loss (1.5 Kg); all subjects completed the experiment, none was exhausted and the "cooling clothes" were appreciated by all subjects. We conclude that the "cooling clothes" tested in the present study significantly reduce the physiological and subjective strain due to intermittent work in a hot environment; this cooling system is simple, of low cost and our results indicate that it is will be very useful in climatic conditions similar to those adopted in the present experimental protocol. Its usefulness in less severe climates has to be established but it might be limited by the subjective reactions of the subjects to the transient but sudden sensation of cold given by the "cooling clothes".

Adaptation, Physiological↗