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Managing electrical risks in the workplace

Riesgos y consecuencias de la electricidad en el trabajo

Workplaces in contact with electricity have a high labour risk level. The severity of these accidents depends on several factors such as high electrical currents or the resistance of human body.

17 june 2016

During this year’s first four months 728 labour accidents related with electricity have occured, according to the Ministry of Employment’s reports. Last year 2.486 accidents happened because of contacting electric current, 11 of them were fatal accidents. Both in 2015 and 2016 most of the accidents were minor.

Labour activities, in which electricity is a very important risk for health and physical integrity, have strict security measures. Workers must know the risks and dangers they are exposed to, as well as preventive measures that they must apply in order to reduce risks. 

In this kind of works, the risk of losing your life because of electricity effects is present. These are some of the consecuences workers of this sector can suffer.

Mortal danger

  • Death by ventricular fibrillation. This is one of the main causes of electrical contact deaths. Electric current through the heart is sudden and fatal and ends with the life of the victims in the large majority of cases.
  • Death by suffocation. It happens when electricity go through thorax and interrupts the breathing of the person affected. 

Mild consequences

  • Tetanic contraction of the muscles It occurs when electric current through human body causes strong muscular contractions and stiffenings which the victim can not control.
  • Burns. One of the most common consecuences are burns caused by electric shocks. It can be mild or serious cases in which afthermaths can cause death.

Factors

The extent of worker’s damages depends on several factors related to electric current’s characteristics that cause these accidents.

  • Current’s voltage is the main factor. It will determine the importance of the electric shock. A 15mA voltage can cause death in 2 minutes. One of 100mA only in 30 secons.

Time of death

  • 15mA 2 minutes
  • 20mA 60 seconds
  • 30mA 35 seconds
  • 100mA 3 seconds

 

  • Contact’s duration: If the victim cannot detach him/herself from the current duration will be longest and the consecuences far worse. If contact duration is reduced to minimum, damages will be much lower.
  • Frequency. The higher the electric current’s frequency is, risks are lower. Currents above 100.000 Hz do not usually cause serious damages.
  • Resistance of the human body. Each body can resist more o less electricity, depending on the resistance of each worker although human body vulnerability is similar to everyone. Human body can resist over 1000 volts.
  • The path of the current. If electric current goes through major organs the probabilities of surviving are very low. On the other hand, if the current goes only through limbs the effects on human body are less serious.