36. Translate these phrases into English.

Измерять уровень влажности, оптимальный уровень, водяной туман, ультразвуковой, переносной, напольная модель, зона охвата, гигрометр, уровень шума, шипение.

GRAMMAR FOCUS

37. Translate the following sentences paying attention to the word worth.

1) There are also models that humidify and purify (or wash) the air - these are usually a more expensive, but may be worth considering. 2) Unless you want to monitor the room's moisture level and adjust settings to maintain it, these measurement features are very handy and worth the extra cost. 3) While it takes some time, it's worth it. 4) The industry accepted definition is that they are privately offered investment vehicles in which the contributions of the high net worth participants are. 5) What Chinese sentences are worth memorizing? 6) It is worth studying for this exam.

LANGUAGE DEVELOPMENT

1) There are various methods of humidity measurement, most of them using a device called a hygrometer. The hygrometer can work in a variety of ways, depending on the type, and is the most accurate method for determining the humidity in the air. Some are connected to other devices called humidistats, which are connected to humidifiers and dehumidifiers, and help control the level of humidity in the air.

One type of hygrometer uses hair, usually human, that is attached to levers inside the unit. When the humidity in the air increases, the hair stretches, and then contracts when it decreases. The levers are generally connected to a dial which displays the humidity reading.

Other methods of humidity measurement using a hygrometer include the psychrometer as well as electric hygrometers. Both methods are fairly accurate, although the electric version is more sophisticated in design. There are also chemical hygrometers that are similar in effectiveness.

The psychrometer, also known as the two-bulb hygrometer, works by using two thermometer bulbs. One bulb is dry and measures the temperature in the air. The other bulb is covered in a substance, usually wick or muslin, and then wetted down. After being wetted, the bulb is exposed to moving air, either through a fan or by slinging the psychrometer through the air. As the water evaporates in the moving air, the temperature on the thermometer will drop. The amount the temperature drops helps to tell the amount of humidity in the air.

This method of humidity measurement is similar to when one goes swimming on a warm breezy day. Before entering the water, the temperature feels warm even with a breeze. If one jumps into the water and becomes wet and then gets back out, the breeze suddenly feels very cool. This is called evaporative cooling. Generally, the lower the humidity in the air, the bigger the drop in temperature.

Electric hygrometers work by measuring the electrical resistance of a particular substance. Most substances, such as lithium chloride, have varying resistances to an electrical current based on the humidity in the air. These differences are then calculated to display the humidity.

Chemical hygrometers work by using a chemical substance and exposing it to air. The chemical will be measured before being exposed and then again after. Any changes in weight indicate how much humidity is in the air.

Although hygrometers are fairly accurate methods of humidity measurement, the most accurate way of testing humidity on a global scale is through the use of satellites. Specialized satellites can detect the exact humidity in the troposphere, thereby giving accurate readings about weather conditions around the world. They are capable of tracking sudden changes in humidity and weather patterns to predict thunder storms, wind, and climate changes.

2) Your home humidity is a measurement of the amount of vaporized water in the air. Humidity levels are naturally higher in warmer climates and lower in cooler climates. The type of home you live in can also affect your humidity measurement. Older and less energy efficient homes are prone to have lower indoor humidity levels, while more modern homes with higher energy efficiency tend to have higher humidity levels.

Both high and low home humidity levels can cause problems. Humidity levels that are too high can lead to peeling paint, mold, and wet insulation. Humidity levels that are too low can cause cracks in your drywall, shrink wood floors, and loosen the joints in wood furniture.

Generally, people are most comfortable when home humidity is between 20 and 60 percent. It is recommended, however, that you keep your home's humidity level between 30 and 40 percent. This is the ideal humidity level because it balances your need for comfort with the conditions that are least likely to cause structural damage to your house.

There are several different strategies you can use for determining home humidity, none of which require the purchase of expensive equipment. Drop three ice cubes into a glass, add water, stir and wait for three minutes; if moisture does not form on the outside of the glass, you may need a humidifier. On the other hand, if you notice frequent fogging of your windows or moisture buildup on closet walls and room ceilings, you may have too much humidity in your home.

Daily activities such as showering, bathing, doing laundry, and cooking all add water to the air in your home. If the humidity level in your home is too high, you should start cooking with pans covered and open a window for a few minutes to bring in cool air after the meal is complete. Taking shorter showers with cooler water may also be helpful for humidity control. If these basic changes don't help correct the problem, using a dehumidifier is recommended.

If your home humidity levels are too low, your skin and hair may feel dry and itchy. The mucous membranes in your mouth and throat may dry out as well, which increases your susceptibility to colds and other illnesses. Purchasing a humidifier for your home is the best way to remedy this problem. Portable humidifiers work by circulating air through a wet pad or a discharging a fine mist into the room. You must add water on a regular basis, but the unit can be moved from room to room as needed.

FOLLOW UP

.Read the texts of Unit 4 again and make notes under the following headings. Then use your notes to talk about Humidification

1)

2)

3)

REVIEW_____________________________Check Your Knowledge

Part 1.