The report describes evaluation of two prototype phase dilution rebreathing masks as compared to an open port rebreathing mask design. Human subjects wearing the prototype masks and engaged in three minute periods of rest and exercise were exposed to altitudes of 14,000, 18,000, 25,000, 30,000 and 34,000 feet in an altitude chamber. Each subject was instrumented to obtain a variety of physiological parameters including end expiratory gas composition, blood oxygen saturation (ear oximetry), ECG, and respiratory rate (impedance pneumograph). Oxygen flow and system pressure as provided by an automatic constant-flow regulator were also determined. The automatic constant-flow regulator when used in conjunction with either of the prototype phase dilution rebreather test masks and proper orifices maintained the subjects' indicated blood oxygen saturations equal to or in excess of their ground level (1,273 feet) baselines. With the same oxygen flow rates the prototype porous and dilution valve masks provided higher tracheal oxygen partial pressures than the open port masks at all altitudes tested during rest and exercise. The prototype phase dilution rebreather masks appear to be more efficient since at the same flow rates a greater amount of oxygen was derived from the supply and less oxygen lost to the ambient environment as compared to the open port type mask. (Author).

This is the Wartime story of Leo Elwood Phillips (1920-2013), one of 11 brothers and sisters that grew up during the Great Depression on a small farm near the Village Of Palestine in Darke County, Ohio. Raised by his mother Bessie after the death of his father Matthew in 1932 from pneumonia, he worked the family farm until graduating from Palestine High School in 1938. He subsequently moved to 19 South Sixth Street in the small Ohio city of Miamisburg to live with his sister Beulah and work as a paper cutter. On 14 May 1942, Leo enlisted as a Private in the Army Air Corps at Patterson Field in Fairfield (Fairborn), Ohio, “ … For The Duration Of The War Or Other Emergency, Plus Six Months, Subject To The Discretion Of The President Or Otherwise According To The Law ...” On 6 June 1942, Leo started classroom training with 12 students at the Bertram School Of Gases, Independent Engineering Company of O’Fallon, Illinois. It is here he became an oxygen and acetylene plant operator - learning to pass air through a series of units that compressed it, removed carbon dioxide, moisture, oil content, and separated liquid air into nitrogen and oxygen. Then, moving liquid oxygen or nitrogen into expansion chambers and finally, compressing oxygen into high pressure cylinders for military aviation use. He completed formal classroom instruction in O’Fallon on the 10th of July and then performed on-the-job training in the Company’s factory until the 17th of September, 1942. From the 2nd to the 16th of November Leo traveled on the troopship SS Monterey from Staten Island, New York to Casablanca, French Morocco, as part of Operation Torch. Shortly after arrival his unit started generating oxygen and filling oxygen cylinders for use on Army Air Forces aircraft such as the B-17 Flying Fortress, B- 24 Liberator and P-38 Lightning. On 30 November 1942, Leo and a number of men he trained with at O’Fallon were transferred from Headquarters and Headquarters Detachment to the 41st Service Group, within the XII Air Force Service Command - a part of Twelfth (XII) Air Force. On 12 February 1943, Leo and his unit were transferred from Detachment XII Air Force Service Command (AFSC) to the 37th Air Depot Group (ADG). On 24 August they were again transferred, this time from Air Force General Depot #3 to Depot #5 within the 37th ADG, XII AFSC. On 26 September 1943, they were transferred (without travel) from the 37th ADG to Headquarters and Headquarters Squadron, 17th Air Depot Group, as part of their anticipated move to recently liberated southern Italy. By August of 1943, newly promoted Sergeant Phillips was generating and filling aviation oxygen in Tunisia and by December was doing the same in southern Italy. All but four of the next 22 months Leo was stationed in and around Bari and Foggia. By mid-1944, all oxygen plant operators in the Mediterranean Theatre of Operations were now attached to the 15th Air Force Service Command (AFSC) Oxygen Detachment, or one of the many Service Groups part of the 15th Air Force. Leo and his men were part of the Oxygen Detachment. From January through October of 1944, the 15th AFSC Oxygen Detachment and Service Groups stationed in Italy collectively filled 225,119 (standard 220 cubic foot) cylinders. The Oxygen Detachment alone was responsible for filling 109,804 – almost half of the total number of cylinders in the Theatre. On 19 November 1944, Leo was promoted to his highest rank, Staff Sergeant (Temporary), while attached to the 18th Air Depot Group. From December 1944 to March 1945, Phillips was sent stateside to Patterson Field near Dayton, Ohio. During this time Leo reported on the status of oxygen generation and use in the Mediterranean Theatre of Operations. While at the Field he also learned how to operate a moisture collector for testing oxygen. He had furloughs during this period from 22 to 29 December 1944 and 22 January to 5 February 1945. For much of this time Leo stayed on Oxford Avenue in Dayton, thus, was able to spend much of his free time with his mother, brothers and sisters now living nearby. Leaving for home permanently on 26 September 1945, Phillips traveled from Naples to New York on the refitted former Italian cruise liner Vulcania. This diesel-powered ship, on its maiden voyage as an allied troopship, was manned by Italian officers and crew. The ship carried 4,057 Americans, including 3,200 Army officers and enlisted men, 557 members of the WAC and 300 nurses. After arriving at Staten Island on 4 October, every soldier was transported to Camp Kilmer in New Brunswick, New Jersey - the largest processing center for troops heading overseas and returning home from World War II. Next, Leo left for Camp Atterbury, Indiana. After further processing to complete the transition from soldier to civilian, Staff Sergeant Phillips received an Honorable Discharge from the 41st Depot Replacement Squadron located at the Separation Center, on 10 October 1945. Soon after coming back home to Miamisburg Leo married Audrey Constance (Case) Phillips and had two children. Audrey was the sister of one of Leo’s closest friends during the War - Ronald A. Case. Leo worked for Burdett Oxygen Company and retired from the Dayton-headquartered bicycle manufacturer Huffy Corporation after 17 years of faithful service. Leo passed on 4 September 2013, after living a rich life which also included tenure as President of the Moose Lodge in Miamisburg, member of St. George's Episcopal Church, Centerville and the love of family, friends, golf, and traveling. CONTENTS: Copyright Independent Engineering Company During World War II Chronology Scrapbook SS Charles Henderson Explosion In Bari Harbor Coming Home On The SS Vulcania Return To The United States - Camp Kilmer, New Jersey Honorable Discharge From Separation Center, Camp Atterbury, Indiana Organizational History Of The 15th Air Force High Altitude Oxygen Cylinders Produced By Firestone Tire and Rubber Company Of Akron, Ohio Generating, Transferring And Using Oxygen Aircraft Oxygen System And Equipment Index of Army and Navy Aeronautical Equipment Volume 3 - Oxygen Equipment - Miscellaneous Equipment Technical Manual 5-351 Gas Generating