| Graceful working could not become reality unless it is in a safe and healthy condition.China is one of the countries in which the number of serious working accidents is the largest, and it is reported that 1 million accidents occurred caused 100 thousand death in many of kinds of accidents every year, which results in hundreds million RMB loss directly.The number of accidents without fire in forestry system has decreased year by year since the reform and opening up, but there were 1000 workers in flesh-wound, 100 workers in serious hurt and 100 death every year, from 2000 to 2004.Available forestry resources with big area distribute in mountainous areas, and plantations with small area are in plain area. As the increasing area of plantation and the landscaping in cities, the portable forest machines, such as shrub cutting machines, chain saws, wind extinguisher, spraying machines, become prevalent gradually. When the workers work with the portable forest machine, the body balance is influenced by the conditions, such as vibrancy, noise, temperature and humidity, caused by the limit of landform sometimes. Consequently, accidents resulted from falling caused by loss of balance happened frequently in the process of work in forest and gardens.This paper studies the influence of physiological load, load, operating postures, temperature, noise and noise protective equipments on body balance with the theory of testing technique and environmental engineering theory of ergonomics, then provide the parameters of body balance, and set up the system of portable forestry and machine personnel selection and operating security prediction, which based on the function of body balance. The main conclusions are as follows:(1)The influence of the working physiological load level (express with heart rate) on function of body balance was very prominent. The extent of the body swaying augmented as the physiological load level increasing; these factors including the total track length of swaying, the total track length of right-and-left swaying, the total track length of fore-and-aft swaying, swaying velocity and heart rate also impacted on body balance. The influence of physiological load on the fore-and-aft swaying is greater than that of the right-and-left swaying.(2)The influence of operating load on the body balance function was very notable. Each index of the body balance function reached the lowest while the load was 9.0 kg when worker stood up straight.(3) The influence of different operating postures on swaying velocity, the total track length of swaying, the total track length of fore-and-aft swaying and other equilibrium indexes was very prominent, but the right-and-left track length of body swaying; In the comparison of different operating postures, body balance was affected by dorsal loading, shoulder loading and handheld loading obviously. And handheld loading had the most obvious effect on body balance, and the next were dorsal loading and shoulder loading; The effect of unilateral loading was the least obvious, and it was less obvious than the effect of natural loading, which should be paid enough attention.(4) The influence of noise and noise protection equipments on body balance was very notable. The noise strength played a very notable role on the total track length of right-and-left swaying, swaying velocity and other indexes, but the total track length of fore-and-aft swaying and the total length of swaying. With the noise strength increasing, the total track length, the track length of fore-and-aft, the track length of right-and-left and swaying velocity all was going to increase linearly, as well as the magnitude of body swaying. The noise frequency and exposure time also were influenced by these above factors.The influence of noise protection on each index of body balance function was very notable. Research indicated that the influence of the noise on body can decline by using the noise protection when working in noise environment.(5)The influence of temperature on the swaying velocity, the total track length of body swaying and the fore-and-aft track length of swaying was notable, but the right-and-left track length of swaying; as the temperature increasing between 18 to 37 centigrade, the total track length, the fore-and aft track length, the right-and-right track length and swaying velocity began to decline.(6)According to the research results, the author established the body balance parameters of healthy people in the situation of nature, physiological load, load, operating postures and working environment.(7) Setting up the system of portable forestry and machine personnel selection and operating security prediction, this was based on the function of body balance. It provided theoretical and technical support to the portable forestry and machine personnel selection and operating security.
|
PDF Full Text Request