The Dynarex Venturi Mask (50/Case) is designed to deliver a known oxygen concentration to patients on controlled oxygen therapy. These masks come with in both adult and pediatric sizes and feature six dilutors which are color-coded based on concentration 8. 35. 8. 40. 10. 50. Venturi mask oxygen flow rates chart above shows the usual flow rate of oxygen and fio2 using the venturi mask from 4 L/min to 10 L/min and 24 % to 50%
Venturi Oxygen Mask 24%, 40%, 50% (100's) quantity. Add to cart. Category: Venturi Oxygen Mask Tag: Venturi Oxygen Mask. Description Reviews (0) Venturi maskes provide a specific % concentration of oxygen. They are well suited for patients at risk of type 2 respiratory failure and especially suited to those with COPD. The % of oxygen. Multi Flow Venturi Mask ₹ 50/Piece. Get Quote. Watch Video. Oxy PAP High Flow Oxygen Venturi Mask With PEEP ₹ 8,000/ Piece Get Latest Price . Country of Origin: Made in India. OxyPAP is customised design for CPAP Therapy that is simply activated by connecting to an appropriate oxygen supply ranging from 15 to 60 LPM. It can be used in a. This type of mask is always set at 15 liters on the flow meter. The mask has changeable plastic pieces, in a variety of colors. Each color signifies a different percentage of oxygen delivery. Venti masks, also called variable or Venturi masks, are capable of delivering between 24 and 50 percent of oxygen NOTE: For patients on a mask, use what is specified on the venturi mask first. Conversion Table for FiO2 when on mask or cannula Nasal Cannula 100 % O2 flow rate (L/min) FiO2 % 1 24 2 28 3 32 4 36 5 40 6 44 Oxygen Mask 100 % O2 flow rate (L/min) FiO2 % 5-6 40 6-7 50 7-8 60 9 90 10 99+ Mask with Reservoir Bag 100 % O2 flow rate (L/min) FiO2 % 6 6
Woolner DF, Larkin J. An anaylsis of the performance of a variable Venturi-type oxygen mask. Anaesth Intensive Care 8:44-50 1980. McPherson SP: Respiratory therapy equipment, Ed 5 St. Louis, MO 1995, Mosby. Roca, O, Riera, J, Torres, F et al. High Flow Oxygen Therapy in Acute Respiratory Failure. Respir Care; 2013 55(4): 408-413 Air Entrainment Mask AirLife® Elongated Style Adult One Size Fits Most Adjustable Head Strap / Nose Clip. Utilizing two oxygen concentration dials, our Venturi-style masks deli Each mask includes color-coded low and medium concentration dials For use with 50 psi oxygen source and flowmete Venturi Mask. Simple delivery of variable oxygen concentrations. Each mask includes color-coded, low-and medium-concentration diluters. Locking ring secures flow setting. Include adaptor for high humidity entrainment. Complete with 7ft oxygen tubing. Diluters: Low concentration for 24%, 26%, 28% and 30%. Medium concentration for 35%, 40% and 50% 2‐6L/min gives approx 24‐50% FIO2 FIO2 depends on oxygen flow and paent's minute volume and inspiratory flow and paern of breathing. Comfortable and easily tolerated No re‐breathing Low cost product Preferred by paents (Vs simple mask
Venturi面罩(Venturi Mask) 利用Bernoulli 原理 氣體流經狹窄（jet），向前的流速增加時，側壁壓力 會降低，可吸入大氣（entrain air）加入主氣流中，以 混合氧氣。 Venturi 流量 由jet 孔徑大小和空氣入口大小比例決定。 通過jet 流量可決定總流量 this video is about venturi mask, color coding,oxygen concentration,flow rate ,uses of mask, slide show are created as a video. This video is helpful for yo..
A Venturi mask -- also known as an air-entrainment mask -- is a medical oxygen delivery mask that utilizes a flow meter to deliver a precise amount of oxygen. Venturi masks are indicated for use in those individuals experiencing chronic or acute respiratory distress, or when an arterial blood gas result indicates a need Multi Flow Venturi Mask. ₹ 50/ Piece Get Latest Price. Material. Medical grade PVC. Six colour diluters for six concentration. 24%, 28%, 31%, 35%, 40% & 50%. Type. General Medical Supplies. Properties Die weichen, bequemen Venturi-Masken für Erwachsene und Kinder von Flexicare werden mit aufgesteckter Venturi-Düse aus dem Bereich 24 % bis 60 % geliefert. Neben Maske und Düse besteht zudem die Möglichkeit, einen Sauerstoffschlauch, einen Reservoirschlauch oder Sauerstoff- und Reservoirschlauch in praktischer Einzelpackung zu kaufen
Venturi mask: 24-50%: Increasing flow will not alter FiO2 Oxygen tent: 10-15: 21-50%: Used mainly on children with croup or pneumonia Simple mask: 5-15: 35-55%: Never used at flows less than 5 L/min to prevent rebreathing of CO2 Trach mask: 10-15: 35-60%: Adequate flow shown by mist flowing out the exhalation port at all times Partial. CAREFUSION MASK VENTURI DUAL DIAL ADULT 50/CS MASK, OXYGEN, LOW CONCENTRATION, VENTURI: Back to Search Results: Model Number 001255-A: Device Problems Use of Device Problem (1670); Misassembly by Users (3133) Patient Problem Low Oxygen Saturation (2477) Event Date 06/09/2010 Vyaire AirLife Dual Dial Venturi-Style Masks Manufacturer: Vyaire Medical, Inc. 2 oxygen concentration dials deliver 9 specific oxygen concentrations ranging from 24% to 55 Venturi Mask; REF Connection type Version Tube length Type VPE; 3120-MMEU: Universal: Standard: 210 cm: Adults: 50: 93227-MMEU: Universal: Standard: 210 cm: Children.
A partial rebreather mask requires 10-15 L/min of oxygen, but only delivers 35-50% FiO2. Venturi Mask. Venturi masks are indicated for patients who require a specific amount of supplemental oxygen to avoid complications, such as those with chronic obstructive pulmonary disease (COPD) 50. Partial Rebreathing Mask. 6-10. Upto 80%. Non Rebreathing Mask. 10. 80-100%. This oxygen delivery devices and flow rates chart shows how many oxygen percentages delivered according to the different flow rates. The percentage of oxygen inspired depends on the flow rate and the delivery device Prior to availability of blood gas measurements, use a 24% Venturi mask at 2-3 L/min or nasal cannulae at 1-2 L/min or 28% Venturi mask at 4 L/min and aim for an oxygen saturation of 88-92%. Initial hospital management of patients with exacerbation of COPD
Air Entrainment Mask AirLife® Elongated Style Adult One Size Fits Most Adjustable Head Strap / Nose Clip. Utilizing two oxygen concentration dials, our Venturi-style masks deli Each mask includes color-coded low and medium concentration dials For use with 50 psi oxygen source and flowmete Salter 8150-7-50 Oxygen Entrainment Mask Kit Percent-O2-Lock® Venturi / 7 Diluter Jets Adult One Size Fits Most Adjustable Elastic Head Strap . Salter's Percent-O2-Lock Venturi masks offer an adjustable, variable venturi system delivering accurate O2 concentrations (24%, 26%, 28%, 31%, 35%, 40%, 50%) from a single unit 1-Pack Westmed #3227-E Pediatric Venturi Elongated Mask Kit. 3.2 out of 5 stars. 3. $6.10. $6. . 10 ($6.10/Count) Get it as soon as Wed, Jun 23. FREE Shipping on orders over $25 shipped by Amazon ベンチュリーマスク（インスピロン）は、不安から患者の心身状態を細かく観察し、何か問題があれば迅速に対処しなければいけません。 ここでは、ベンチュリーマスク（インスピロン）の看護に関して詳しく説明していますので、適切なケアを実施できるよう、看護師の方は是非参考にして. The concentration of oxygen provided in the inspired gas by five samples of a venturi mask were measured at ground level and at altitudes up to 10,000 ft for each of the oxygen port settings from 24-50% oxygen. The concentration of oxygen provided at a given setting was virtually identical for each
Modern Venturi masks come with one or more color coded caps, and whichever one you use the desired liter flow for that particular cap is written right on the cap. The Venturi Masks used at MMC are set up as follows: A. White cap: 35% FiO2 set lpm at 9 ; 40% FiO2 set lpm at 12 ; 50% FiO2 set lpm at 15 ; B. Green cap: 24% FiO2 set lpm at 3lp La maschera di Venturi consiste in una maschera, di grandezza standard, anatomica, anallergica, in materiale sintetico, flessibile e monouso. E' caratterizzata da un foro cui viene collegato un condotto, dal diametro di 2 cm circa, che termina con una valvola che permette di variare la concentrazione di O2 che si desider Venturi masks. There is entrainment of room air with these devices, but it is fixed and not dependent on the patient's PIFR. Therefore the resulting delivered FiO2 is also constant. Non-rebreather facemasks. These masks contain a resevoir bag which is connected to the mask with a one-way flap valve, preventing expired gas entering the reservoir. VENTURI OXYGEN MASK 24%; 40%; 50 %. Reviews There are no reviews yet. Be the first to review VENTURI OXYGEN MASK 24%; 40%; 50 % Cancel reply. Your email address will not be published Face mask, venturi, adult, single use. Face mask to provide oxygen at flow rates between 1 - 10 LPM. Allows for precise oxygen delivery by utilizing different sized port to change FiO2 (24 - 50%). Also known as air-entrainment masks able to provide total inspiratory flow at a specified FiO2
Venturi mask. Fixed Concentration Mask. 20120-20123. Easy adjustable, variable venturi system ensures fixed & accurate concentrations of oxygen. Low concentration (Green colour) diluter allows settings of approximately 24%, 26%, 28% & 30%. Medium concentration (White colour) diluter allows settings of approximately 35%, 40% & 50% Pediatric Venturi mask with flex tube Full Set of Color-Coded Oxygen Diluters (24%, 28%, 31%, 35%, 40%, 50%) 7' (213 cm) Tubing Humidification cup View 9 View 30 View 60 View 90 Showing 1-9 of 1
It includes: venturi mask, venturi type nebulizers (Fail > .50 FiO 2), high flow blender system. Gas injection nebulizer (GIN) -works for all FiO 2 s. 2. Low flow system. It is the one through which O 2 is delivered to supplement the patient's tidal volume Venturi Mask (Venti Mask) 24%-50% Fi O 2 with flow rates as recommended by the manufacturer, usually 4-10 L/min; provides high humidity: Perform constant surveillance to ensure an accurate flow rate for the specific Fi O 2. An accurate flow rate ensures Fi O 2 delivery. Keep the orifice for the Venturi adaptor open and uncovered
Participants: Cardiac surgery patients presenting oxygen saturation <96% with Venturi mask 50%. Intervention: Oxygenation by HFNC (45 L/min, F I O 2 100%) or Hudson RCI non-rebreather face mask with a reservoir bag (15 L/min). Measurements and main results: The co-primary outcomes were the PaO 2 /F I O 2 ratio at 1 and 24 hours The Venturi mask is often utilized in the COPD patient population where the risk of knocking out the patient's hypoxic drive is of concern. Likewise, when would you use a Venturi mask? Venturi masks , calibrated to deliver Fio 2 between 24% and 50%, are most useful in patients with COPD as they allow the Po 2 to be titrated, thus minimizing the. A simple mask can deliver oxygen at a concentration of about 28-50% [10] at a flow rate of 5- 10 LPM (Litres per minute). Indication. Mild to moderate respiratory distress [12] Non-rebreather mask (Hudson mask) Components. Face mask with 2 one-way valves-The face mask covers both nose and mouth. A one-way valve is present between the reservoir.
Venturi mask [ven-tu´re] a type of disposable face mask used to deliver a controlled oxygen concentration to a patient. (See also oxygen therapy.) The flow of 100 per cent oxygen through the mask draws in a controlled amount of room air (21 per cent oxygen). Commonly available masks deliver 24, 28, 31, 35, or 40 per cent oxygen. At concentrations above. With NHF, the gas flow rate was 50 L/min. The Venturi mask or the NHF were applied for 48 hours or up to ICU discharge. Arterial blood gases, Sa O 2,FIO 2 SET, respiratory rate, mean arterial pressure, heart rate, and patient discomfort were recorded at 1, 3, 6, 12, 24, 36, and 48 hours Venturi Mask, Pediatric, 6dil, 7' Tubing, 50/cs- Effectively deliver controlled amounts of oxygens to patients while keeping them comfortable in thi
Utilizing two oxygen concentration dials, these Dual Dial Venturi-Style Adult Masks deliver nine specific oxygen concentrations ranging from 24% to 55% O 2.They accomodate adult patients. For use with 50 psi oxygen source and flowmeter Wholesale Distributor of Respiratory Care Disposables - Adult Oxygen Mask, Pediatric Oxygen Mask, Pediatric Multi Flow Venturi Mask and Adult Multi Flow Venturi Mask offered by Lifelinx Surgimed Pvt. Ltd., Chennai, Tamil Nadu Due to high demand for MEDSOURCE PVC Adult Venturi Mask Kit, Clear/White, availability is subject to change without notice. Menu. $143.00 / pkg. of 50 Qty. Please enter a numeric value Add to Cart.
Than a Venturi Mask3 Beecroft JM, Hanly PJ. Comparison of the OxyMask and Venturi mask in the delivery of supplemental oxygen: Pilot study in oxygen-dependent patients. Can Respir J. 2006;13(5):247-252. Objective Measure the efficiency and safety of OxyMask compared to a venturi mask in delivering oxygen to patients with chronic hypoxemia. Method Venturi Mask (if available): If the patient does not improve, try a Venturi mask, which provides more precise oxygen delivery between 24-60% via an entrainment device that mixes air with oxygen. Up-titrate based on patient symptoms up to 60% using specified oxygen flow rates (typically 2-15 LPM) (5) Fraction of Inspired Oxygen (FiO2) for a nasal canula and a Venturi mask are given in the tables below. For other oxygen delivery systems, such as masks, tents, there is more oxygen that blows by or is lost, therefore higher flow rate setting on the oxygen tank are needed to achieve the same FiO2 Salter Labs® Percent-O2-Lock® Venturi System is a transparent, elongated tube delivering accurate concentrations of oxygen (from 24 to 50%) with a single unit. Assembly comes with 7 foot oxygen supply tube and humidity cup. 50 per Case. Choose with or without elastic strap/band. Recommended for long-term users or edentulous patients
Venturi mask; adult, paediatric 2-15 L/min 24-60% oxygen, according to the type of mask Allows precise measurement of FiO 2 delivered Utilizes different sized ports to change the FiO 2 delivered (24-50%) Some brands relate a colour to a flow rate and FiO In these circumstances, a lower Fi o 2 may be required such as 2-4 l/min via a medium concentration mask (equivalent to approximately 28%-40% oxygen) or preferably by the use of controlled oxygen at 24% or 28% via a Venturi mask titrated upwards or downwards to maintain an oxygen saturation of 90%-92% pending the results of blood gas. Venturi mask is designed for conveying oxygen gases through mouth, and the concentration of oxygen can be adjusted. CE certified product. Features: Venturi mask (with two diluters): Two color coded diluters for seven concentration. Green diluter for 24%, 26,%, 28%, 30%; and White diluter for 35%, 40%, 50%. Venturi mask (with 6 diluters
For example, Maggiore and colleagues found that applying 50 liters per minute of HFNC for 48 hours after extubation substantially reduced NIV use and reintubations compared with a Venturi mask (3.8% vs. 21.2%) in patients who had passed a spontaneous breathing trial, but whose Pa O 2 /F i O 2 ratio was less than 300 Venturi Mask With 6 Diluters is known as Venturi Mask With Six Adopter The venturi mask is also known as an air-entrainment mask which is used to deliver oxygen concentration to patients on controlled oxygen therapy. This mask is a replacement for intermittent oxygen treatment. Venturi masks are considered high-flow oxyge
Additional Information: Latex content: Latex-Free Disposable / Reusable: Disposable Brand: AirLife® Feature / Property: Humidification Hood, Crush Resistant Tubing, Six Diluter Jet for 24/28/31/35/40/50% Oxygen Concentration Mask Type: Venturi Under-the-chi A partial rebreather mask typically delivers 50 to 70 percent oxygen. Simple oxygen mask. A simple oxygen mask has no reservoir bag and no valves. It typically delivers 35 to 55 percent oxygen. Facial mask / Venturi 8057-0-50 Salter Labs Adult nasal cannula / oxygen 1699-14-50 Salter Labs Pneumatic nebulizer / disposable 8984-7-50 Salter Labs Adult nasal cannula / oxygen 1606TLC-0-25 Salter Labs Oxygen nasal cannula Petite Salter Labs Load More
Om 33/1, 4th Cross, Sampige Road, Malleswaram, Malleshwaram West, Bengaluru - 560003, Dist. Bengaluru, Karnataka. TrustSEAL Verified. Company Video. View Mobile Number. Call +91-8048742846. Contact Supplier Request a quote. High Concentration Oxygen Mask. ₹ 130/ Piece Get Latest Price. High Concentration Oxygen Mask with 1 ltr bag La maschera di Venturi o Ventimask è una tipologia particolare di maschera dell'ossigeno utilizzata nell'ossigenoterapia in acuto, terapia medica con lo scopo primario di correggere l'ipossiemia, ovvero la riduzione della pressione parziale dell'ossigeno nel sangue. Composizione della maschera. È composta da una.
E-mail: kyoling@kyoling.com 我们的地址：中国 杭州 杭州经济技术开发区 16 号大街 9 号 电话 Tel ： 0086-571-86840896 传真 Fax ： 0086-571-86840897. 杭州京泠医疗器械有限公司版权所有 9031401 903140 50% Pediatric Venturi Mask Kit, Adjustable diluter (24%, 26%, 28%, 31%, 35%, 40%, 50%) Elongated oxygen mask with nose clip, 2.1m (7') No-crush oxygen tube, Fits-All connector 2.1m (7') * Products may not be available in all countries. Please contact your regional ConvaTec sales representative for further information Venturi Oxygen Mask 24%; 40%; 50 % ----- Venturi Oxygen Mask 24%; 40%; 50 %. Name *. Email *. Save my name, email, and website in this browser for the next time I comment description Adult Tracheostomy Mask is a comfortable, easy-to-use mask ideal for tracheostomy and laryngectomy aerosol therapy. This adult tracheostomy mask with a 360-degree swivel accepts 22mm I.D. and corrugated tubing. Adult Tracheostomy Mask comes with an adjustable neck strap that fits most sizes (one size fits all). Designed to be comfortable, lightweight and reliable, this tracheostomy. 50 MP01920 O2Star™ Medium concentration oxygen mask with conn. tube 2.1 m, disposable, M/L 50 MP01921 O2Star™ Venturi mask kit, adjustable venturi valve, disposable, M/L 25 MP01922 O2Star™ Venturi mask kit, fixed venturi valve, disposable, M/L 25 MP01923 O2Star™ Tracheostomy mask, disposable, M/L 50 MP01924 O2Star™ Face tent.
Venturi masks provide a more predictable oxygen concentration to the patient. The masks are available in the following concentrations: 24%, 28%, 31%, 35%, 40% and 50% depending on the colour-coded mask attachment used. They are suitable for all patients needing a known concentration of oxygen. The 24% and 28% Venturi masks are particularly. Venturi mask (high-flow system) High-flow system consisting of a bottle of sterile water, corrugated tubing, a drainage bag, air/oxygen ratio nebulizer system, and a mask that works with the corrugated tubing. The mask may be an aerosol face mask, tracheostomy mask, a T-piece, or a face tent. The key is that the flow of oxygen exceeds the peak. sal-8058-7-50,8058-7-50,salter labs,adult venturi system w/out mask 50/cs,venturi adult assem hum cup no mask 50cs,preferred medica Masks, Cannula, Headsets, Venturi Valves Tubing & Connectors. Oxygen Tubing & Connectors Oxygen Tubing & Connectors. browse all £12.50 Inc VAT. Add to Basket. Pack of 10 5/32 x 5/32 Barbed Elbow. £12.50 Inc VAT. Add to Basket. Pack of 10 3/16 Straight Tubing Connectors. £9.50 Inc VAT
Tracheostomy Mask 50% Venturi Mask - Adult - PBTM00051 - 2.1m tubing . Use by date 06/2023. VAT Registered, hence you can claim back VAT. VAT Invoice sent with all orders. Visit our EBAY shop for more first aid & medical items. If you require bulk please call us on 01530 839115. UK stock. All items are CE marked where appropriate. Deliver Since the venturi mask is a high-flow device, it is rarely useful for FiO 2 greater than 50%. Flow Devices in Kathmandu There are a few authorized dealers in Kathmandu, Nepal that deals with these kinds of flow devices Venturi Mask • High flow device • Allows precise measurement of O2 delivered • Utilizes different sized ports to change amount of FiO2 (24% to 50%) • Useful in COPD patients where precise O2 prescription is crucial KorupoluR GJ, Needham DM.Contemporary CriticalCare. 2009;6(9):1‐11 Baile Venturi mask. 4-12 LPM, 24-50%. aerosol mask / face tent @ least 10 LPM, 24-100%. Sets found in the same folder. Week 6: Nutrition. 35 terms. angar11 PLUS. Electrolyte Imbalances. 47 terms. angar11 PLUS. Week 1: Infection Prevention and Control. 18 terms. angar11 PLUS
Oxygen masks - fixed oxygen concentration (high flow) A range of adult and paediatric concentration oxygen masks and kits offering fixed oxygen concentration (high flow). Venturi valves. Venturi valve Intersurgical EcoLite™ mask kits. Intersurgical EcoLite™ adult venturi mask kit. Oxygen recovery kit Venturi mask merupakan metode pemberian oksigen yang paling akurat dan dapat diandalkan untuk konsentrasi oksigen yang tepat melalui cara non invasif. Masker dibuat sedemikian rupa sehingga memungkinkan udara ruangan bercampur dengan aliran oksigen yang telah ditetapkan. Masker ini digunakan terutama bagi pasien PPOM karena memberikan suplemen oksigen tingkat rendah, sehingga menghindari.
Increased mouth breathing of room air will dilute the oxygen for a lower FiO2 overall, which is why a venturi mask (constant FiO2 at a constant minute volume) is the most certain way to deliver a particular FiO2. And yes, if a COPDer needs more than 50% FiO2 to maintain a SaO2 of 88% and are getting sleepy, they need a vent Severe hypoxemic acute respiratory failure (hARF) due to pneumonia (defined as PaO2/FiO2 ratio of at most 250 evaluated during oxygen therapy supplied for at least 15 min through a Venturi mask with an FiO2 of at least 0.50) RR of at least 30BPM; Respiratory distress; Exclusion: Need for immediate intubatio 벤츄리마스크 (Venturi mask) 수술실/마취기구/ 흡인되어 산소와 혼합되므로 결과적으로 환자는 혼합가스를 흡입하게 되는데 이것이 Venturi마스크의 원리이다.. Calculate the air-to-oxygen ratio in venturi masks. 3. Calculate total gas flow from venturi masks. 4. Analyze the delivered FIO2 from a venturi mask 5. Measure the total gas flow from a venturi mask. EQUIPMENT 1. oxygen administration devices a. nasal cannula b. medium concentration mask c. partial rebreathing mask d. nonrebreathing mask e. 888.758.3688. or. Email Us. Description. Reviews. These Adult Venturi-style masks feature six diluter jets ranging from 24% to 50% FlO2. All masks are under-the-chin style and are supplied with a 6€Â flextube, humidification hood, and 7´ tubing
AirLife® adult Venturi-Style Air Entrainment Mask with 7 Foot crush resistant tubing, humidification hood and 6 diluter jets (24%,28%,31%,35%,40% and 50% Modern Venturi masks come with one or more color coded caps, and whichever one you use the desired liter flow for that particular cap is written right on the cap. The Venturi Masks used at MMC are set up as follows: A. White cap: 35% FiO2 set lpm at 9; 40% FiO2 set lpm at 12; 50% FiO2 set lpm at 15; B. Green cap: 24% FiO2 set lpm at 3lp Simple face mask rate. greater than 5L/min. venturi mask rate. 4-15L/min. venturi mask FiO2. 25-50%. Nonrebreathing mask rate. greater than 60% at 10-15L/min. nonrebreathing mask FiO2. 60-80%. Sets with similar terms. EMT - O2 delivery, tanks, rates, and masks. 24 terms. izzynobre Maschera di Venturi. La maschera di Venturi o ventimask è il sistema migliore per conoscere approssimativamente la FiO2 somministrata in quanto è una maschera che copre naso e bocca a cui si adatta una valvola colorata che permette di garantire una determinata FiO2. Cambiando la valvola cambia la quantità erogata Background Venturi masks are commonly used in the hospital setting to deliver controlled percentages of oxygen. This is important for those at risk of hypercapnic respiratory failure and to accurately assess ventilation and gas exchange. Hospital oxygen supplies deliver high velocity and pressure, which are required for Venturi masks to operate as designed