Objective Evaluation of Earplugs for the Control of Water-Borne Infection

1981 ◽  
Vol 90 (1) ◽  
pp. 89-93 ◽  
Author(s):  
David W. Johnson ◽  
Robert H. Maisel
Keyword(s):  
Water Pressure ◽  
Objective Evaluation ◽  
Solid Core ◽  
Petroleum Jelly ◽  
Clinical Protocol ◽  
Water Penetration ◽  
Polymeric Foam ◽  
Patient Use ◽  
Water Borne ◽  
Inhibited Water

Eighty-two cotton, foam, and solid core stock and custom earplugs were evaluated objectively for water absorption and water penetration characteristics in order to determine their efficacy for control of water-borne infection in ears having open middle ear cavities. Cotton plugs, even when saturated with petroleum jelly, had poor consistency in resisting even minimal water pressure. Polymeric foam plugs, especially when saturated with petroleum jelly, appeared to inhibit water flow in conditions approximating actual ear protection use. No plugs evaluated, including custom elastomeric solid core plugs, inhibited water penetration in conditions approximating shallow surface dives. A clinical protocol for evaluation of potential earplugs for patient use is proposed on the basis of this study.

Ear protection against water-borne infection: an objective evaluation

1986 ◽  
Vol 100 (12) ◽  
pp. 1337-1340 ◽  
Author(s):  
Kyösti Laitakari ◽  
Martti Sorri ◽  
Tapio Pirilä ◽  
Heli Löppönen ◽  
Laila Helisten
Keyword(s):  
Middle Ear ◽  
Objective Evaluation ◽  
Petroleum Jelly ◽  
Ear Canal ◽  
Polymeric Foam ◽  
Plastic Materials ◽  
Ear Canals ◽  
Water Borne

AbstractEight different ear plug materials were tested, in 5 ears each, in artificial shallow underwater conditions for 30 minutes, in order to determine their efficacy in sealing the ear canals to avoid water-borne infections in ear canals and open middle ears. Most of the plugs tested would meet everyday requirements for protection, but the polymeric foam plugs, treated with petroleum jelly, and moldable plastic materials were most effective in protecting both the middle ear and the ear canal skin.

A Study on Water Penetration of Concrete under Water Pressure to Develop the Anti-Corrosion Repair System

2007 ◽  
Vol 348-349 ◽  
pp. 425-428
Author(s):  
Joh Yeong Yoo ◽  
Han Seung Lee ◽  
Sung Ho Tae ◽  
Moon Byung Chul
Keyword(s):  
Porous Material ◽  
Porous Materials ◽  
Penetration Depth ◽  
Water Pressure ◽  
Steel Frames ◽  
Repair System ◽  
Water Penetration ◽  
Rust Inhibitor ◽  
Durability Of Concrete

As concrete is a type of porous materials, water or air freely permeates concrete. Therefore the durability of concrete decreases. However, porous material with a rust inhibitor may allow permeation of water into concrete. In addition, there may be permeation of water through the rust inhibitor at the location of steel frames. The objective of the study is to investigate the penetration depth of concrete under water forced conditions with pressure.

scholarly journals In-Situ and Laboratory Investigation on Leaching and Effects of Early Curing of Shotcrete

2019 ◽  
Vol 61 (2) ◽  
pp. 23-37
Author(s):  
Andreas Sjölander ◽  
Anders Ansell
Keyword(s):  
Water Pressure ◽  
Test Method ◽  
Test Results ◽  
Water Penetration ◽  
Sprayed Concrete ◽  
Future Studies ◽  
One Year ◽  
Rock Tunnel ◽  
Short Time

Abstract During the construction of a rock tunnel in Stockholm, several sections with leaching shotcrete (sprayed concrete) were found one year after the spraying was completed. An investigation was therefore conducted, and its results are presented in this paper. The amount of leaching after such a short time indicated that a one-sided water pressure existed in combination with a permeable shotcrete. The reason for the water pressure was likely a partly unsuccessful grouting that created sections with leaking water. The permeable shotcrete could be a combined result of insufficient curing and the use of accelerators, and the effect of in-situ curing was therefore investigated. A total of six slabs were sprayed and cured under different conditions in the tunnel. Test results according to standards indicated that curing has no significant effect on the development of mechanical strength or water penetration through the shotcrete. However, this is believed to be a result of the test method rather than the non-existing effect of curing. Lastly, some modifications to the test standard were proposed for future studies of in-situ curing.

Experimental Study on the Water Penetration into Mortar under Water Pressure Condition

2008 ◽  
Vol 385-387 ◽  
pp. 681-684 ◽  
Author(s):  
Joh Yeong Yoo ◽  
Han Seung Lee ◽  
Young Jin Kim
Keyword(s):  
Experimental Study ◽  
Corrosion Inhibitors ◽  
Water Pressure ◽  
Applied Pressure ◽  
Pressure Condition ◽  
Water Penetration ◽  
Moisture Migration ◽  
Steel Bars ◽  
Conventional Technology ◽  
Corrosion Of Steel

Concrete is a type of porous materials and is physically and chemically damaged due to exposure to various environments from the placing to the service life. These reactions affect the corrosion of steel bars applied in concrete and that decreases the durability life and strength of such steel bars. Thus, it is very important to insert rust inhibitors into steel bars in the case of a deterioration element that exceeds the critical amount of corrosion in the location of steel bars. However, it is very difficult to guarantee corrosion resistance at the location of steel bars using conventional technology that applies corrosion inhibitors only on the surface of concrete. This study attempts to develop a method that penetrates corrosion inhibitors up to the location of steel bars and investigate the penetration depth of corrosion inhibitors by verifying moisture migration in concrete under an applied pressure.

scholarly journals Water Penetration of Concrete made with Coarse Aggregates from Demolishing Waste

2020 ◽  
Vol 10 (6) ◽  
pp. 6445-6449
Author(s):  
M. F. Koondhar ◽  
B. A. Memon ◽  
M. Oad ◽  
F. A. Chandio ◽  
S. A. Chandio
Keyword(s):  
Penetration Depth ◽  
Water Pressure ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Destructive Testing ◽  
Water Penetration ◽  
Standard Size ◽  
Conventional Concrete ◽  
Coarse Aggregates ◽  
Maximum Loss

The results of laboratory investigations on water penetration in concrete made with coarse aggregates from demolishing waste are presented in this paper. Seven batches of standard size concrete cubes were cast with recycled aggregates from demolished concrete replacing coarse aggregates in percentages from 0% to 60%. The compressive strength of the samples was evaluated by non-destructive testing with the use of the Schimidz hammer. It was found that the strength reduces with an increase in recycled aggregate percentage. The maximum loss of strength due to the induction of recycled aggregates was 32% in the batch with 60%recycled aggregates. All samples were subject to constant water pressure of 5 bars for 72 hours. From the obtained results it was shown that the water penetration depth increases with increase in recycled aggregates rate. With 10% and 20% replacement the samples allowed less water to penetrate than conventional concrete samples, but 76% more penetration depth was recorded in samples with 60% replacement. Strength and water penetration results from dosages up to 20% show that the durability of the produced concrete allows it to be used in structural members with consideration of strength reduction in the design process. However, more water penetration with higher dosages of recycled aggregates needs proper care in design and usage of the concrete particularly for locations where concrete is exposed to water pressure.

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