Position:Technical Library

The electric safety of hospital equipment is analysed

From;    Author:Stand originally

Equipment of instrument of electronic medical treatment and report are relevant, if use undeserved, defend undeserved, measure not do one's best, also can protect personnel to bring tip-and-run risk to patient or cure, cause person to endanger. Accordingly, in job of clinical medical treatment how equipment of instrument of safe use medical treatment, reduce electrical shock accident to lowermost rate, it is a problem that is worth to take seriously highly. And more serious problem is: In medical treatment is checked or treating a process, we should take what step, ability ensures the patient avoids the risk that suffers electrical shock injury.

One, effect of human body report

Electrical shock is electric current passes the phenomenon that the certain physiology that human body causes reacts. Human body is conductance body, when human body makes the one part of circuit, electric current passes human body, cause electrical shock thereby. Electrical shock causes physiology effect and the immediate cause that human body injures is electric current. The size of the electricity that carries human body depends on the human body impedance between two interface and the impedance of two interfaces and the tension that are increased at human body. The impedance of human body is more complex, it is nonlinear when the network that change, the electric current of the weld time that this conclusion can be differred and different frequency, the phasic difference that differs through existing between the voltaic intensity with human body different generation and electric current and voltage will prove.

Of human body the outerest it is the skin with electric very poor capacity, its are the outerest call skin, by composition of hyaline layer and corneous layer, bead layer. Impedance of experimental proof skin basically depends on corneous layer, its ply is different, impedance is different. One square centimeter dry nondestructive hurts the skin, its block is worth limits to be Ω of 10 ~ 1000K, particular numerical value still depends on body place and humidity. The internal resistance of each limbs fights human body is 200 Ω , truncal internal resistance is fought it is 100 Ω about, the impedance between two limbs is random about 500 Ω .

Say commonly, below constant tension, the volume that carries human body electricity depends on the size of human body impedance, and the size of human body impedance basically suffers effect of the following element again:

1. Cutaneous condition. The thickness that includes cuticular and corneous layer, cutaneous is dry reach crude rate to wait.

2. Voltaic frequency. In identical contact the condition falls, total impedance of the human body when voltaic frequency is tall is small, total impedance of the human body when voltaic frequency is low is big, below dc circumstance, human body resistor reachs maximum.

3. Contact a condition. When get an electric shock, electrified metal and skin are sectional go up to still be put in complex ion exchange process, dc can produce become acute phenomenon to increase osculatory resistance thereby, alternating current can produce displacement electricity and reduce the resistance of human body.
Previous12 Next

Related Articles
Hot Concern
Random Recommendation
Column list

About us | Legal Notices | Sitemap | links | Partner