Cylinder Manifold Research Articles

Retrospective evaluation and comparison of oxygen supply management with piped supply with cylinder manifold in first wave of COVID-19 against piped supply with liquid medical oxygen system in second wave of COVID-19

Background: COVID-19 infection is a major health pandemic all over world started in 2019. Due to respiratory tract involvement, major number of patients required oxygen supplementation. Dedicated COVID hospitals and others required high burden of oxygen all over world. During first wave, oxygen supply management to main hospital building of our institute was by the central piped supply with cylinder manifold whereas during second wave, it was piped supply with 20 KL liquid medical oxygen (LMO) SYSTEM. Aims and Objectives: With this background, we decided to compare these both systems by questionnaire-based interview of healthcare worker and data evaluation. We planned to conduct this study with aim to compare effectiveness and ease of oxygen supply management with both these oxygen supply systems. Materials and Methods: We took questionnaire-based interviews of oxygen store people, intensive care unit, and ward in charge sisters and doctors and manpower working at oxygen supply systems. Results: Both systems of oxygen supply provided uninterrupted supply of oxygen during COVID outbreak with statistically significant less stress level of healthcare workers, good pressure constancy, less cost, and more ease of operability of LMO system. Conclusion: During daily high demand of oxygen, LMO system is superior than piped supply with cylinder manifold system.

Medical gas pipeline system as a limiting factor for hospital oxygen supply during COVID-19 outbreak.

Medical gas pipeline system as a limiting factor for hospital oxygen supply during COVID-19 outbreak.

Hospital Oxygen Supply: A Survey of Disaster Preparedness of Indian Hospitals

Background: Uninterrupted oxygen supply is an essential hospital facility. Careful planning is needed to prevent major mishaps in case of failure. We undertook a survey to assess vulnerability of oxygen supply systems to disasters. Methodology: Hospitals in South India were stratified and randomized based on their bed strength. A structured telephonic interview was done to the managers of engineering departments in these hospitals. The questionnaire included type of oxygen source, location, changeover mechanism, and alarm systems. Results: Of the 30 hospitals randomized, adequate information was obtained from 25 hospitals. The primary source of the supply was cylinder manifolds in 48%, liquid oxygen in 40%, and concentrators in 12% hospitals. A reserve source of oxygen supply was available in 64% hospitals; 44% with cylinders, and 20% with liquid oxygen. Only 52% of the hospitals had a reserve supply in a different location from the primary. Changing the source of supply was manual in 44% of hospitals and 20% had an automatic change over system installed. There were effective zonal and central alarms in only 12% of hospitals. Conclusion: Most of the hospitals rely on a single pipeline from a single location inviting mishaps during the disasters. Contingency planning to reduce the risk of an uninterrupted supply should involve automatic changeover systems to a backup source with physically separated feed lines. Primary, secondary, and reserve supply could involve the use of liquid oxygen, oxygen concentrators, or cylinder manifold systems in various combinations depending on the size of hospital, proximity to a liquid oxygen plant and risk.

Asymptotic behaviour of instantons on cylinder manifolds

In this article, we study the instanton equation on the cylinder over a closed manifold X which admits non-zero smooth 3-form P and 4-form Q. Our results are (1) if X is a good manifold, i.e., P, Q satisfying $$d*_{X}P=d*_{X}Q=0$$, then the instanton with integrable curvature decays exponentially at the ends, and, (2) if X is a real Killing spinor manifold, i.e., P, Q satisfying $$dP=4Q$$ and $$d*_{X}Q=(n-3)*_{X}P$$, we prove that the solution of instanton equation is trivial under some mild conditions.

The cylinder manifold piecewise linear system: Analysis and implementation

The cylinder manifold piecewise linear system: Analysis and implementation

1P1-I07 油圧トロコイドポンプ付シリンダブロックアクチュエータの特性評価(力制御型液圧駆動ロボット(2))

The actuator for robot hand need to be powerful enough to hold its whole weight and flexible enough to avoid damage by the collision with the environment. We developed a back drivable 14 degrees of freedom electro hydrostatic cluster actuator for tendon driven robot hand combining direct casted cylinder manifold and trochoid gear pump with crescent separator. Its basic design and prototype was showed previously. In this paper, we finished it as a cluster actuator and evaluated its static property such as maximum output force, moving speed and their dispersion. Its ability of force measurement is also evaluated.

A reply

As a supplier of medical gas cylinders, BOC are concerned about the inherent risk associated with the wrong cylinder being used where cylinders are supplied with non-gas specific connections. BS 381 is the basic standard that prescribes the different valve outlets that should be used for industrial, medical and research grade gas cylinders in the UK. This standard has been in place for over 50 years and utilises the 5/8 inch BSP (F) bull-nose connection for many gases. These include oxygen, air, argon, nitrogen, helium and their mixtures in both medical and industrial service. As identified in this incident, there is a risk that the end user can mistakenly attach the wrong cylinder to the patient supply system, causing the wrong gas to be administered to the patient. Whereas the incident was very serious and could have had serious consequences for the patient, had the regulator been attached to a helium or argon cylinder (both used in medical applications) the consequences would have been much more serious. In the 1980s it was recognised that there was a risk that medical air and medical oxygen cylinders could be used incorrectly on cylinder manifolds and the valves used on these cylinders were changed to a pin index type. The pin index outlets, detailed in ISO 407, provide both a gas-specific and service-specific outlet for medical gas cylinders. At this time BOC requested that other cylinders should also be converted to pin index valve outlets but this request was rejected because of the cost of converting all of the regulators in the hospital service. It was reported that the risk was less with the F and G size cylinders as they were used for the administration of gas local to the patient where it was possible for the responsible person to identify the correct gas by the cylinder colour coding and the label. Although there are many thousands of these cylinders in service, there have been a number of reports of ‘near misses’ with the wrong cylinders being connected. To try and mitigate this potential risk of supplying the wrong gas to the patient, BOC has taken steps to assist the end users in selecting the correct package. The introduction of new cylinders fitted with an integrated cylinder valve (that have a built-in pressure regulator) has meant that a standard terminal outlet connection can be fitted to the valve outlet. The terminal outlet has a product specific connection, preventing the wrong equipment being connected to the cylinder. With the changes in the regulations for colour coding cylinders, the new types of cylinders now being supplied have the name of the gas clearly visible on the cylinder body. The new collar label has meant that both the product name and the user instructions are now more legible to allow the person administering the gas to check the contents more easily. Unfortunately it is not possible to convert all cylinders to the new type of valve overnight and the reported incident identifies the need to train all personnel appropriately to ensure that the correct cylinder is being used. In addition, it is very important to manage cylinder stores correctly to segregate the different gases (and to not mix the medical and non-medical cylinders). This will assist in the correct cylinder being selected by the porter for supply to the ward or operating theatre. It is also important to minimise the number of cylinders being stored in those areas where the gas is used, to make it more difficult for the wrong cylinder to be selected. These issues should be identified by the routine risk assessments of the hospital and be addressed by the appropriate corrective actions detailed to address the potential risks. This is a subject that concerns all of the medical gas cylinder suppliers in the UK. The British Compressed Gas Association (BCGA) have talked to the MHRA about how this issue could be addressed. It would be helpful if similar incidents could be reported to me to enable a consolidated view of the potential risk to be presented to the authorities in support of proposals concerning the change to gas- and service-specific medical gas cylinder valve outlets.

Factors Affecting Ammonia Volatilization from Sewage Sludge Applied to Soil in a Laboratory Study

AbstractA forced‐air polyvinyl chloride (PVC) cylinder manifold chamber was used to collect ammonia (NH3) volatilized from sewage sludges applied to soil in the laboratory. A series of experiments were conducted in which the effect on NH3 volatilization of a single variable was studied. The reference control conditions were: Columbus, Ohio anaerobically digested liquid sewage sludge applied at 5 Mg ha−1 (dry wt) to a Crosby silt loam soil (pH 6.7) at 0.01 MPa initial moisture tension. The soil was bare and the sludge was unincorporated during the 24‐h study period. Air temperature was 26 ± 2°C. The variable conditions were: (i) initial soil moisture (0, 0.01, 1.5 MPa and air‐dry); (ii) time of incorporation (0.25, 1, 3, 6, 12, and 24 h after sludge application); (iii) soil pH (5.1, 6.7, 7.5); (iv) sludge type (anaerobically digested Columbus liquid sludge, partially dewatered Columbus anaerobic sludge, aerobically digested Medina liquid sludge, lime stabilized primary Ashland sludge, and composted primary Columbus sludge); (v) temperature (12.8, 18.3, 26.7°C); and (vi) vegetative cover [bare, grass sod (Poa pratensis), wheat straw (Triticum aestivum)].Initial soil moisture contents ≤1.5 MPa tension increased NH3 volatilization compared with air‐dry soil. Volatilization increased linearly with time elapsed before sludge incorporation. Ammonia loss was greater from soil at pH 7.5 than at pH 6.7 or 5.1. There was significantly greater loss of NH3 from the lime‐stabilized sludge (pH 12) than from the anaerobic and aerobic sludges. No detectable NH3 was lost from the compost. Volatilization decreased with decreasing temperature. When the sludge contained large sludge particles, NH3 loss increased with vegetative cover. However, cover had no effect when the sludge was well homogenized. For all experiments, 24‐h volatilization losses ranged from 0 to 32% of the NH3‐N applied.