Treatment Equipment: Patien Security

Glossary

Electricity: Interaction between matter and their particles (protons and electrons) that produce a flow of energy known as current.

Earth: Is a mechanism of security to protect patients or humans of electric shocks that deviate the leakage currents and give a the value of reference in a circuit with magnitude around of 0.5 to 2.5 V.

Live Wire: Is the phase that have the positive cargue of electricity, contains all the magnitude of current, and it can have several value in altern current (AC) as 110V, 220V or more that are known as single-phase and two phase circuits respectively. But it too might be three-phase or more and be direct current (DC).

Neutral: Is the part of a phase that is designed to protect the dispositives, equipments and all machines that are pluged in to electricity. This too have a value so closer to zero, their magnitude with respect to Earth alike is aproximately zero and with the Live Wire, it should measure the normal phase of supply.

Safety: Thet are the mechanisms, methods and process that are developed to safeguard any specific object or being of diversy types of dangers and prevent damage, injuries, diseases, accidents, inter alia.

The patient security consider the features in a enviromental medical, the medical equipments, risks, electrical system, medical procedures, and interaction with patients. For example, the electrical outlets in anyplace or room of a hospital must have a correct classification of color (medical configuration, gray color), perfect connection to earth and neutral, so they must be in a good condition, with the required height and features as demand the normativity in Colombia (by 4445 Resolution of 1996 and 2003 Resolution of 2014) and enforce all the aspects to protect patients and prejudice in a better way accidents and injuries. So is important that electrical outlets have a control of electricity safety, to that asistencial personal, biomedical professionals and patients take cautions with injuries or death, burns, electrick shocks, falls, electrocution while they are making direct contact with overhead wires, making manteinance, or working with damage electrical equipment.
For this reason, is important that the biomedical engineer makes sure about measures of electrical measure, so in a laboratory of practices of Treatment Equipments and Support in Manuela Beltrán University were take this measures with a multimeter and screwdriver tester:

TERMINALS	VOLTAGE MULIMETER (AC)
LIVE – NEUTRAL	116.7 V
LIVE – EARTH	116.3 V
EARTH - NEUTRAL	0.171 V

Table 1. Measures of Voltaje in electrical output with a multimeter

Image 1. Voltaje between Live Wire and Neutral.

In case that can exist damage or incorrect values o voltaje, it can cause a potencial hazard to dispositives or medical equipments and human being in the area.

Image 2. Voltaje between Live Wire and Earth.

Image 3. Voltaje between Earth and Neutral.

According to the intesity of current, the hazard to damage or cause an effect in the human body are more complex; in 1mA it feel a tingling berely perceptible, between 1-3mA is when a person can feel the current in the perception threshold, in the scale of 3-9mA it cause painful sensation. Until 25mA it cause muscular contractions and after this magnitude it can present respiratory paralysis, ventricular fibrillations, heart paralysis and inclusive tissue burning.

Image 4. Live wire with screwdriver tester

To identify the Live wire, Earth and Neutral in a electrical output, generally it is designed of the same way in Colombia and the majority of latin-american countries; line shortest is the Live Wire, line or output longest is Neutral and the another output is Earth (bear in mind that it is to one-phase electrical power supply).