PPV gives you complete control over where the exhaust air travels by choosing the exhaust opening. With Positive Pressure Ventilation, you blow into the structure and literally “pressurize” the entire structure. This gives you the ability to ventilate the entire structure of dust particles, heat, gas, smoke or any other type particulate temporarily suspended in the air.

There is a complete explanation of Positive Pressure Ventilation principles and applications on our web site. Go to the main page and click on the link that says “PPV”. Firefighters and Industry users alike may also want to purchase a copy of the video “Positive Pressure Attack” directed by former Los Angeles Battalion Chief John Mittendorf, available on our web site. See similar questions...

Besides the color, the difference is the size of the battery post. Positive posts are slightly bigger (larger diameter) than the negative posts. That's why those cheap "universal" battery terminals never fit quite right. They're too small for the positive post and too big for the negative. See similar questions...

The LMA ProSeal™ is designed for use with PPV. Its ability to give a higher seal pressure at lower mucosal pressures means that patients can be safely ventilated at higher pressures than with the LMA Classic™. Dr. Brain's study shows that, at a given intracuff pressure, the LMA ProSeal™ gives twice the seal pressure than the LMA Classic™. See similar questions...

Positive pressure is when a room inside the building is held at a higher pressure than the surrounding rooms. Or to put it another way, positive pressure occurs when more airflow is pumped into a room then airflow drawn out. This ensures any air leaks in the room will flow from inside the room to the outside. This is most commonly used in clean room applications to prevent airborne contaminants from outside the room leaking in. See similar questions...

Negative pressure is when a room inside the building is held at a lower pressure than the surrounding rooms. Or to put it another way, negative pressure occurs when more airflow is drawn out of a room then airflow pumped in. This ensures any air leaks in the room will flow from outside the room to the outside. This is most commonly used in hospital isolation rooms to prevent airborne viruses or bacteria from escaping the room into other rooms. See similar questions...

To me positive cash flow means: that after all expenses of owning and managing your rental property have been met, you will have a cash surplus from your properties BEFORE any tax refunds are taken into consideration. At worst, you will be looking for a break-even situation. Because Land Tax is an expense that only certain investors with larger property holdings incur, I do NOT allow for Land Tax in my positive cash flow calculations. See similar questions...

False negative results are more common than false positives - and are primarily due to inaccuracies in timing of the test or carelessness in the test procedure itself. Please follow test instructions with circumspection and precision. A false negative result can also stem from using a diluted urine sample and/or from taking a test too early in pregnancy. First morning urine contains the most concentrated presence of hCG - which makes it the ideal sample for pregnancy testing. See similar questions...

With Autosomal Dominant PKD, the only form of PKD so far identified and confirmed in cats, two genetic negative parents cannot produce a genetically positive offspring unless that offspring is a fresh mutation. See the discussion on autosomal-dominant inheritance below for further details. See similar questions...

In most areas of the country ground water starts to produce a column of water pressure that is exerted on basement walls normally starting from two to four feet below surrounding ground level. This water column or "natural hydraulic pressure" tries to equalize it's pressure by flowing to cracks or porous imperfections in your basement walls, footings, and floors. See similar questions...

A positive (sometimes called additive) technique is where you add glaze to the surface with your applicator. A negative (sometimes called subtractive) technique is where you apply a thin layer of glaze to the surface with a roller or brush, and then remove the glaze with your applicator. The positive techniques show more of the original Base Coat color, while the negative techniques show more of the glaze color. See similar questions...

Do not attempt to interpret results after the five minute test reaction time. Depending on the concentration of hCG in the test specimen, positive results may be observed in as little as 40 seconds. However, to confirm negative results, the complete reaction time of 5 minutes is required. A positive result can only be determined within this time interval. See similar questions...

Being negative can be very positive. There is a difference between being nihilistic and being negative in the sense of being cautious and critical before believing a claim or accepting an explanation for something. A nihilist denies the value of everything. Many religious people are nihilists since they deny the value of anything in this world. The leaders of religions often reject family, reproduction, the joys of the body, the pleasures of art and nature. See similar questions...

The three most common PVC pressure pipe products manufactured by Uni-Bell member companies are ASTM D2241, AWWA C900 and AWWA C905. The following information will briefly explain the differences between the “Pressure Class” and “Pressure Rating” design philosophies employed in these three standards. AWWA C900 has a “Pressure Class” design approach based on a 2.5 safety factor. Pressure Class is formed using a 2.5 safety factor versus the 2. See similar questions...

Low pressure is 1 – 10 psi and does not need an external air supply source. Airsleds use a self-regulating blower that automatically adjusts to increases in weight. The system is contained and portable. High pressure is over 10 psi, needs an external air supply source and an air regulator. See similar questions...

Low pressure units emit both UVA & UVB at a lower energy level. Low pressure units are the traditional beds you normally think of when you think of tanning beds. To build your base tan in low pressure units, you'll usually start off with about ? of the recommended maximum tanning time and increase by a minute or two with subsequent visits*. High pressure units give you immediate results. By filtering out the UVB rays (burning rays), you can tan quickly without burning. See similar questions...

Urine drug test may have picked up an over-the-counter medication or prescription. The confirmatory test will determine the difference in the substance detected. See similar questions...

The Pap test is a screening test and, like any such test, it is not 100-percent accurate. Although false positive and false negative results do not occur very often, they can cause anxiety and can affect a woman's health. A false positive Pap test means that a patient is told she has abnormal cells, but the cells are actually normal. A false negative Pap test occurs when a specimen is called normal, but the woman has a significant abnormality that was missed. See similar questions...

Yes, we request our patients to attend the support group, and ask other patients questions. It is also a great opportunity to learn how to be a successful gastric bypass patient. The more you attend support group, the better your results. See similar questions...