Cylinders and Color coding And Different Gases

Cylinders and Color coding And Different Gases

1. Cylinders and their Color-coding System Ahmad Ullah

2. CYLINDERS • Cylinders are made of thin-walled molybdenum steel to withstand high pressures, e.g. 13 700 kPa and 4400 kPa for oxygen and nitrous oxide, respectively. Lightweight aluminum is also available. • They are made in different sizes: size E cylinders are used on the anesthetic machine; size J cylinders are used in cylinder banks.

3. Oxygen cylinders contain gas whereas nitrous oxide cylinders contain a mixture of liquid and vapour . • At a constant temperature, the pressure in a gas cylinder decreases linearly and proportionally as it empties. This is not true in cylinders containing liquid/ vapour . • They are colour -coded (shoulder and body). A new colour system is being introduced with white bodies but different coloured shoulders.

4. Critical temperature is the temperature above which a substance cannot be liquefied no matter how much pressure is applied. The critical temperatures for nitrous oxide and oxygen are 36.5°C and − 118°C, respectively.

5. Different Test Uses for Cylinder Cylinders in use are checked and tested by manufacturers at regular intervals, every 5–10 years. Test details are recorded on the plastic disc between the valve and the neck of the cylinder. They are also engraved on the cylinder: 1. An internal endoscopic examination is carried out. 2. Flattening, bend and impact tests are carried out on at least one cylinder in every 100. 3. A pressure test is conducted, whereby the cylinder is subjected to high pressures of about 22 000 kPa , which is more than 50% above their normal working pressure. 4. A tensile test is carried out on at least one cylinder in every 100, whereby strips of the cylinder are cut out and subjected to impact, stretching, flattening and other tests of strength .

6. The marks engraved on the cylinders are: 1. Test pressure. 2. Dates of test performed. 3. Chemical formula of the cylinder’s content. 4. Tare weight (weight of nitrous oxide cylinder when empty).

7. LABELLING OF CYLINDER The cylinder label includes the following details: • Name, chemical symbol, pharmaceutical form, specification of the product, its l icense number and the proportion of the constituent gases in a gas mixture. • Substance identification number and batch number. • Hazard warnings and safety instructions. • Cylinder size code. • Nominal cylinder volume (liters). • Maximum cylinder pressure (bars). • Filling date, shelf life and expiry date. • Directions for use. • Storage and handling precautions.

8. PIN INDEX SAFETY SYSTEM The pin index system is a safety mechanism used primarily in the medical field to prevent the incorrect connection of gas cylinders to their associated regulators and equipment. It’s particularly crucial in settings like hospitals where different gases (such as oxygen, nitrous oxide, and medical air) need to be accurately delivered. Pin Configuration : Each gas cylinder has a unique pin configuration on its valve that corresponds to specific pins on the regulator or equipment that attaches to it. The pins are placed in different positions to match with the holes in the valve, ensuring that only the correct gas can be attached to the appropriate equipment.

9. Safety : The pin index system prevents errors by physically preventing the connection of an incorrect gas cylinder to a regulator. For example, an oxygen cylinder will have a different pin configuration than a nitrous oxide cylinder. This design helps avoid dangerous mix-ups, such as connecting a wrong gas to a patient's breathing apparatus.

10. MEDICAL GASES It is defined as gases which are manufactured packed and intended for giving to a patient for diagnosis, therapy and t o p r oduce anesthesia. It is c on si de r e d as drugs and their use without medical practitioner is unsafe.

11. MEDICAL GASES oxygen Carbon dioxide Nitrogen Helium Nitrous oxide Nitrous oxide N2O Laughing gas

12. OXYGEN Within the hospital environment oxygen is usually found in 3 main areas Critical care areas Operating theatres Most wards, A&E & treatment therapy areas

13. INTRODUCTION It is important for all living cells. It is necessary for normal metabolism for the production energy. O xygen is combined with hemoglobin converted into oxy hemoglobin which dissociate and release oxygen to the cell. Requirement of oxygen in body is classified into:

14. Anoxic Inadequate supply of oxygen to the tissue Anemic Inadequate amount of hemoglobin to supply the oxygen to the tissue. this is due to hemorrhage, carbon monoxide poisoning etc. Carbon dioxide has more binding affinity towards hemoglobin only oxygen administration is not effective for the condition. A c arbon d i o xid e o x y g en mi x tu r e [hyperbaric oxygen ] is used for this condition.

15. S t a g na n t It occurs du e t o the inadequa t e g en e r al circulation or retardation of local circulation. Oxygen is not used in this case whereas cardiotonic drugs are used to speed up the circulation. Histotoxic It occurs due to interferences of tissue cell oxidation or uncoupling of oxidative phosphorylation or cyanide poisoning. Histotoxic hypoxia refers to  a reduction in ATP production by the mitochondria due to a defect in the cellular usage of oxygen . An example of histotoxic hypoxia is cyanide poisoning.

16. use of oxygen It is used as inhalant in anesthesia post operative condition, burns and wounds. Osmotic condition, gaseous poisoning and artificial respiration. It is mixed with 5-7% CO2 which is used for stimulating respiratory center. The mixture of oxygen and helium 21:79 is used for patients with severe lung damage. LABELLING The shoulder of cylinder should be painted white, and the remainder should be painted black . The cylinder should carry a label stating oxygen along with this, oxygen or the symbol O2 should be stenciled in paint on the shoulder of the cylinder.

17. Nitrous Oxide (N2O) All Blue Nitrous Oxide is used: As an inhalation anesthetic as part of a balanced maintenance of a General Anesthetic. Only medical personnel trained in the appropriate techniques should administer nitrous oxide

18. Uses of NO2 In General anesthesia for producing analgesic and anesthetic effect. A mixture of 1:1 ratio with oxygen is used for the relief of pain in child birth and heart attack and Myocardial infarction. Calming the excited psychiatry patients. To induce anesthesia. Nontoxic in nature frequently used in dental practice. Quickly absorbed anesthetic. labelling The cylinder is painted with blue color with the name nitrous oxide and the symbol N2O or the name should be stenciled in paint on the shoulder of the cylinder.

19. Entonox • A compressed gas mixture with 50% oxygen and 50% nitrous oxide by volume at a pressure of 13 700 kPa. • A two-stage pressure demand regulator is usually used. • Liquification and separation occurs at temperatures below − 5.5°C (Poynting effect). This can potentially lead to hypoxic mixtures. Large cylinders are designed to prevent this.

20. CARBON DI OXIDE Carbon dioxide is insufflated into the abdominal cavity to distend it to allow investigation & treatment of intrabdominal disease and for laparoscopi c surgeries. Carbon dioxide should only be given under the direct supervision of a clinician.

21. Air contains 0.03% v/v of CO2 Sources Volcanoes Dead bodies decay Respiration Combustion Fermentation

22. Uses of C02 The mixture of 95: 5 [ ratio of CO2: O2 ] is used in the treatment of carbon monoxide poisoning for increasing the ventilator exchange rate and dissociation rate of CO from hemoglobin. Inhalation of CO2 h as been used for Anxiety and relaxation. Detoxification of heroin addicts Dry ice as temperature of - 80C is used to remove warts. 6% carbon di oxide is toxic. labelling The shoulder of the cylinder should be painted grey and having the name and symbol of CO2 stenciled with paint on it.

23. Heliox ( 21%O 2 /79%He), brown with white quartering Heliox is a mixture of helium and oxygen and is often used in emergency situations where upper or lower airways are partially obstructed, but may also be used within an Intensive care setting for those patients receiving both invasive and noninvasive ventilation. Heliox should be administered via appropriate equipment calibrated for the gas mixture.

24. Helium It contains NLT 99% by volume of He It is the second highest element in the periodic table. It is used as a diluent in oxygen administered during mucosal plug obstructions, laryngeal edema etc . The low density of helium helps to reduce the work of breathing and improves airflow through obstructed airways.

25. Uses of He Helium - oxygen mixture are easier to breathe by patients with severe lung damage or with obstructions in upper respiratory tract. Helium breathing may also influence vocal pattern and vocal pitch.

26. Storage It should be stored and supplied in brown colored metal cylinder . Mixtures of oxygen and helium in the ratio of 20-21 % and 79-80% v/v re also supplied in cylinders which are painted black on the body and white and brown batches on the shoulders and neck.

27. Nitrogen I t i s im p or t a n t c o n s titu e n t of ani m al and p l a n t tissues; largely present as amino acid and proteins. It is used as diluent for pure oxygen It is used as an antioxidant. The increased concentration of nitrogen in blood leads to narcosis. It is obtained by fractional distillation of liquid air