Medical gases are used for patient’s healthcare in different ways. In the early of 1950s, healthcare providers recognised the hazards of using heavy high pressure cylinders of medical gases. Instead, medical gases and vacuum systems are provided by medical gases pipeline system (MGPS). It is safe, permanent and cost-effective mean of provision. In general, medical gases are specific gases that are separated from the air individually for various medical applications. Commonly used medical gases in hospitals are Oxygen (O2) • Nitrous oxide (N2O) • Medical air 400 KPa or 4 bar (MA 4) • Medical air 700 KPa or 7 bar (MA 7) • Carbon dioxide (CO2) • Nitrogen (N2) • Medical vacuum Oxygen (O2) Oxygen is the most important gas on the earth; it formed about 21 per cent of the natural air. In application, it is used as a medical gas to sustain life. Moreover, it is used to drive anesthesia machines and ventilators in addition to other methods for manual ventilation. Three sources are used for oxygen supply; vacuum-insulated evaporator (VIE) or bulk tank, cylinders, and oxygen concentrator (PSA) system. Further, oxygen is coded in white color. Nitrous oxide (N2o) Nitrous oxide is a medical gas administrated via anesthesia machine. It is mixed with oxygen and various anesthetic agents. Therefore, operating rooms are sole location of nitrous oxide. Usually a manifold supply system is the source of nitrous oxide gas. Cylinders are coded with blue color as well as the pipelines. Medical air 4 bar In general, medical air 4 is used for respiratory applications. The source of supply can be a medical gas manifold system or a medical compressor system. The color code is black color. Medical air 7bar Medical air 7 is known as surgical air because it is used mainly to derive some surgical equipment such as tourniquet and bone saw. The supply source is similar to medical air 4. Carbone dioxide (CO2) Carbone dioxide is a medical gas used for insufflations purpose in open heart surgery and laparoscopy procedures. Usually portable cylinders are the source of CO2 which are coded with grey color. Nitrogen N2 Nitrogen for surgical power tools is likely to be used only on the sites where it is available for the production of synthetic air. Medical vacuum Medical vacuum is provided by means of a vacuum central plant. The vacuum system should always be used in conjunction with vacuum control units that include vacuum jars. In fact, it is not a gas, it is a negative pressure used for suctioning patients and for anesthetic gas scavenging system. Typically, vacuum is delivered at pressure of 400 mmHg (53 KPa) below atmospheric pressure. Vacuum pipes are known with its yellow color. System components Each medical gas must be supplied from a separate system. It is essential that all parts of each system are gas specific to ensure that there is no possibility of cross-connection between systems. Indeed, a common configuration is designed to each system as shown in Fig.1 including the following components. Sources Piping networks Valves Warning and alarm systems Outlets and inlets Secondary equipment Sources Sources are supplies that produce the flow of medical gases through piping networks. There are four main sources for medical gases: Bulky systems It consists of special insulated vessels, vaporizers, and regulators. Theses systems can be constructed with cryogenic vessels or a high-pressure manifold, depending on the usage. Typically, oxygen, nitrous oxide, and carbon dioxide are supplied to large hospitals in cryogenic tanks. Manifold systems It consists of high pressure cylinders on 2 banks; one is a back-up to the other. In addition, main control panel is installed for primary and secondary regulators, pressure regulators, and warning lamps. Figure 2 presents an example of manifold systems for nitrous oxide. Medical air treatment systems Medical air treatment systems are usually 2 or more compressors equipped with a receiver, derivers, regulators, filters, dew point monitors, and carbon monoxide alarms. Produced air should be free of dust and moisture. Vacuum pumps Vacuum pumps are mechanised devices that create a negative pressure in the piping system. The pumps should alternate automatically. A reservoir tank is used for storage to permit cycling on and off instead of continuous operation. Each pump should be capable of maintaining 75 per cent of calculated demand during peak time. Piping networks Medical gases and vacuum are distributed via the pipeline distribution system to provide gas or vacuum at the end-point or terminal units. The terminal units may be either wall-mounted or pendant-mounted. The pipes should be made of high quality copper, seamless type, and non-arsenic. Moreover, it should be protected against physical damage and corrosion and color coded as per gas content. Valves There are 2 types of valves; zone valves and service valves. Zone valves are used to isolate large parts of the system, i.e. rooms for modification and/or repair. In addition, zone valves are placed on corridor walls and should be labeled to indicate the rooms that they control. On the other hand, service valves are used to isolate certain part of the system for modification and/or repair. Accordingly, they are accessible by the clinical staff. Warning and alarm systems The function of warning and alarm systems is to give information for the responsible staff about the whole plant in case of failure detection or change requirement. This includes the sources, the pipes, the valves, etc. Therefore, there are 2 main alarm systems; master alarms and area alarms. Master alarm monitors the main gas lines and sources conditions. Area alarms are found on alarm panels and their function is to monitor the conditions of specific critical care area. According to NFPA standards, both master and area alarms must be reviewed and checked regularly. Outlets and inlets Outlets are points at which connections can be made to the medical gas piping system to supply gases under pressure, while inlets are supply vacuum. There are 2 styles of connections; quick connect and twist-on. Secondary equipment While hoses, gas flow meters, gauges,… Continue reading MGPS