RTD THEORY

Loss in dielectrics

An efficient dielectric supports a varying charge with minimal dissipation of energy in the form of heat. There are two main forms of loss that may dissipate energy within a dielectric. In conduction loss, a flow of charge through the material causes energy dissipation. Dielectric loss is the dissipation of energy through the movement of charges in an alternating electromagnetic field as polarisation switches direction.

Dielectric loss is especially high around the relaxation or resonance frequencies of the polarisation mechanisms as the polarisation lags behind the applied field, causing an interaction between the field and the dielectric’s polarisation that results in heating. This is illustrated by the diagram below (recall that the dielectric constant drops as each polarisation mechanism becomes unable to keep up with the switching electric field.)

Dielectric loss tends to be higher in materials with higher dielectric constants. This is the downside of using these materials in practical applications.

Dielectric loss is utilised to heat food in a microwave oven: the frequency of the microwaves used is close to the relaxation frequency of the orientational polarisation mechanism in water, meaning that any water present absorbs a lot of energy that is then dissipated as heat. The exact frequency used is slightly away from the frequency at which maximum dielectric loss occurs in water to ensure that the microwaves are not all absorbed by the first layer of water they encounter, therefore allowing more even heating of the food.

The dielectric constant and the refractive index

The refractive index of a material, n, is defined as the ratio of the speed of light in a vacuum to the speed of light in that material.

 where c is the speed of light in a vacuum and cm the speed of light in the material.

It is possible to derive another equation for the speed of light, this time in terms of the electric permittivity (ε) and magnetic permeability (μ) of the material. For this, we need Maxwell’s equations.

              (1)
           (2)

Taking the curl of both sides of (1) allows us to combine (1) and (2):

In general for any vector a:

Now in a vacuum, . In this case the above equation becomes:

Which is the wave equation in three dimensions. Let us consider the 1D equivalent, as this is easier to solve.

A possible solution to this equation is a sinusoidal wave of wavelength λ and speed c:

Differentiating with respect to x and t:

And substituting back into the 1D wave equation above:

Which can be simplified and rearranged to give an expression for c, the speed of light in a vacuum:

It turns out that a similar equation is applicable to the speed of light in any material, cm:

For a material that is not magnetic the permeability is μ0, so that:

 for any non-magnetic material.

Using the expressions for c and cm, the refractive index of the material can be expressed in terms of ε and μ.

Finally, recall the earlier definition of the dielectric constant in terms of permittivity:

Therefore κ = n2 .

The dielectric constant

The dielectric constant of a material provides a measure of its effect on a capacitor. It is the ratio of the capacitance of a capacitor containing the dielectric to that of an identical but empty capacitor.

An alternative definition of the dielectric constant relates to the permittivity of the material. Permittivity is a quantity that describes the effect of a material on an electric field: the higher the permittivity, the more the material tends to reduce any field set up in it. Since the dielectric material reduces the field by becoming polarised, an entirely equivalent definition is that the permittivity expresses the ability of a material to polarise in response to an applied field. The dielectric constant (sometimes called the ‘relative permittivity’) is the ratio of the permittivity of the dielectric to the permittivity of a vacuum, so the greater the polarisation developed by a material in an applied field of given strength, the greater the dielectric constant will be.

There is no standard symbol for the dielectric constant – you may see it referred to as κ, ε, ε′ or ε_r. In this TLP κ shall be used to avoid confusion with the absolute permittivity, which may also be given the symbol ε.

The two definitions of the dielectric constant are illustrated by the diagram below (the green arrows represent the electric field).

In general, the more available polarisation mechanisms a material possesses, the larger its net polarisation in a given field will be and hence the larger its dielectric constant will be.

The dielectric constant of a material and its refractive index are closely linked by the equation κ = n² . However, care must be taken in applying this equation. It is only strictly accurate when the dielectric constant and the refractive index are measured under the same conditions. Specifically, since the dielectric constant can vary significantly with frequency (for reasons discussed in the next section of this TLP), we must measure the dielectric constant under alternating current at the same frequency that we measure the refractive index at – the frequency of visible light, ~10¹⁵ Hz. However, quoted values of the dielectric constant normally refer to the static dielectric constant – that is, the dielectric constant under direct current. This is often very different from the value of the dielectric constant at 10¹⁵ Hz.

The exception to this is for materials that possess only the electronic mode of polarisation. For these materials, the dielectric constant does not vary significantly with frequency below visible frequencies, and κ_S ≈ n² where κ_S is the static dielectric constant.

To summarise: the equation κ = n² can be applied to the static dielectric constants of non-polar materials only, or to the high-frequency dielectric constants of any dielectric.

Dielectric material

A dielectric material is a substance that is a poor conductor of electricity, but an efficient supporter of electrostatic field s. If the flow of current between opposite electric charge poles is kept to a minimum while the electrostatic lines of flux are not impeded or interrupted, an electrostatic field can store energy. This property is useful in capacitor s, especially at radio frequencies. Dielectric materials are also used in the construction of radio-frequency transmission lines.

In practice, most dielectric materials are solid. Examples include porcelain (ceramic), mica, glass, plastics, and the oxides of various metals. Some liquids and gases can serve as good dielectric materials. Dry air is an excellent dielectric, and is used in variable capacitors and some types of transmission lines. Distilled water is a fair dielectric. A vacuum is an exceptionally efficient dielectric.

An important property of a dielectric is its ability to support an electrostatic field while dissipating minimal energy in the form of heat. The lower the dielectric loss (the proportion of energy lost as heat), the more effective is a dielectric material. Another consideration is the dielectric constant , the extent to which a substance concentrates the electrostatic lines of flux. Substances with a low dielectric constant include a perfect vacuum, dry air, and most pure, dry gases such as helium and nitrogen. Materials with moderate dielectric constants include ceramics, distilled water, paper, mica, polyethylene, and glass. Metal oxides, in general, have high dielectric constants.

The prime asset of high-dielectric-constant substances, such as aluminum oxide, is the fact that they make possible the manufacture of high-value capacitors with small physical volume. But these materials are generally not able to withstand electrostatic fields as intense as low-dielectric-constant substances such as air. If the voltage across a dielectric material becomes too great -- that is, if the electrostatic field becomes too intense -- the material will suddenly begin to conduct current. This phenomenon is called dielectric breakdown . In components that use gases or liquids as the dielectric medium, this condition reverses itself if the voltage decreases below the critical point. But in components containing solid dielectrics, dielectric breakdown usually results in permanent damage.

Electrical Safety

Electrically powered equipment, such as hot plates, stirrers, vacuum pumps, electrophoresis apparatus, lasers, heating mantles, ultrasonicators, power supplies, and microwave ovens are essential elements of many word areas. These devices can pose a significant hazard to workers, particularly when mishandled or not maintained. Many electrical devices have high voltage or high power requirements, carrying even more risk. Large capacitors found in many laser flash lamps and other systems are capable of storing lethal amounts of electrical energy and pose a serious danger even if the power source has been disconnected.

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Electrical Hazards

The major hazards associated with electricity are electrical shock and fire. Electrical shock occurs when the body becomes part of the electric circuit, either when an individual comes in contact with both wires of an electrical circuit, one wire of an energized circuit and the ground, or a metallic part that has become energized by contact with an electrical conductor.

The severity and effects of an electrical shock depend on a number of factors, such as the pathway through the body, the amount of current, the length of time of the exposure, and whether the skin is wet or dry. Water is a great conductor of electricity, allowing current to

flow more easily in wet conditions and through wet skin. The effect of the shock may range from a slight tingle to severe burns to cardiac arrest. The chart below shows the general relationship between the degree of injury and amount of current for a 60-cycle hand-to-foot path of one second's duration of shock. While reading this chart, keep in mind that most electrical circuits can provide, under normal conditions, up to 20,000 milliamperes of current flow 

 

Current	Reaction
1 Milliampere	Perception level
5 Milliamperes	Slight shock felt; not painful but disturbing
6-30 Milliamperes	Painful shock; "let-go" range
50-150 Milliamperes	Extreme pain, respiratory arrest, severe muscular contraction
1000-4,300 Milliamperes	Ventricular fibrillation
10,000+ Milliamperes	Cardiac arrest, severe burns and probable death

In addition to the electrical shock hazards, sparks from electrical equipment can serve as an ignition source for flammable or explosive vapors.

Even loss of electrical power can result in extremely hazardous situations. Flammable or toxic vapors may be released as a chemical warms when a refrigerator or freezer fails. Fume hoods may cease to operate, allowing vapors to be released into the work area. If magnetic or mechanical stirrers fail to operate, safe mixing of reagents may be compromised.

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Preventing Electrical Hazards

There are various ways of protecting people from the hazards caused by electricity, including insulation, guarding, grounding, and electrical protective devices. Workers can significantly reduce electrical hazards by following some basic precautions:

	Inspect wiring of equipment before each use. Replace damaged or frayed electrical cords immediately.
	Use safe work practices every time electrical equipment is used.
	Know the location and how to operate shut-off switches and/or circuit breaker panels. Use these devices to shut off equipment in the event of a fire or electrocution.
	Limit the use of extension cords. Use only for temporary operations. In all other cases, request installation of a new electrical outlet.
	Use only multi-plug adapters equipped with circuit breakers or fuses.
	Place exposed electrical conductors (such as those sometimes used with electrophoresis devices) behind Plexiglas shields.
	Minimize the potential for water or chemical spills on or near electrical equipment.

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Insulation

All electrical cords should have sufficient insulation to prevent direct contact with wires. It is particularly important to check all cords before each use, since corrosive chemicals or solvent vapors may erode the insulation.

Damaged cords should be repaired or taken out of service immediately, especially in wet environments such as cold rooms and near water baths.

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Guarding

Live parts of electric equipment operating at 50 volts or more (i.e., electrophoresis devices) must be guarded against accidental contact. Plexiglas shields may be used to protect against exposed live parts.

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Grounding

Only equipment with three-prong plugs should be used. The third prong provides a path to ground that helps prevent the buildup of voltages that may result in an electrical shock or spark. This does not guarantee that no one will receive a shock, be injured, or be killed. It will, however, substantially reduce the possibility of such accidents, especially when used in combination with other safety measures.

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Circuit Protection Devices

Circuit protection devices are designed to automatically limit or shut off the flow of electricity in the event of a ground-fault, overload, or short circuit in the wiring system. Fuses, circuit breakers, and ground-fault circuit interrupters are three well-known examples of such devices.

Fuses and circuit breakers prevent over-heating of wires and components that might otherwise create hazards for operators. They disconnect the circuit when it becomes overloaded. This overload protection is very useful for equipment that is left on for extended periods of time, such as stirrers, vacuum pumps, drying ovens, Variacs and other electrical equipment.

The ground-fault circuit interrupter, or GFCI, is designed to shutoff electric power if a ground fault is detected. The GFCI is particularly useful near sinks and wet locations. Since GFCIs can cause equipment to shutdown unexpectedly, they may not be appropriate for certain apparatus. Portable GFCI adapters (available in most safety supply catalogs) may be used with a non-GFCI outlet.

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Motors

In areas where volatile flammable materials are used, motor-driven electrical equipment should be equipped with non-sparking induction motors or air motors. Avoid series-wound motors, such as those generally found in vacuum pumps, rotary evaporators and stirrers. Series-wound motors are also usually found in household appliances such as blenders, mixers, vacuum cleaners and power drills. These appliances should not be used unless flammable vapors are adequately controlled.

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Safe Work Practices

The following practices may reduce risk of injury or fire when working with electrical equipment:

	Avoid contact with energized electrical circuits.
	Disconnect the power source before servicing or repairing electrical equipment.
	When it is necessary to handle equipment that is plugged in, be sure hands are dry and, when possible, wear nonconductive gloves and shoes with insulated soles.
	If it is not unsafe to do so, work with only one hand, keeping the other hand at your side or in your pocket, away from all conductive material. This precaution reduces the likelihood of accidents that result in current passing through the chest cavity.
	Minimize the use of electrical equipment in cold rooms or other areas where condensation is likely. If equipment must be used in such areas, mount the equipment on a wall or vertical panel.
	If water or a chemical is spilled onto equipment, shut off power at the main switch or circuit breaker and unplug the equipment.
	If an individual comes in contact with a live electrical conductor, do not touch the equipment, cord or person. Disconnect the power source from the circuit breaker or pull out the plug using a leather belt.

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High Voltage or Current

Repairs of high voltage or high current equipment should be performed by trained electricians. Individuals who are experienced in such tasks and would like to perform such work on their own equipment must first receive specialized electrical safety related work practices training by EHS staff. 

The following additional precautions should be taken:

	Always assume a high voltage potential exists within a device while servicing it, even if it is de-energized and disconnected from its power source.
	Avoid becoming grounded by staying at least 6 inches away from walls, water, and all metal materials, including pipes.
	Use voltmeters and test equipment with ratings and leads sufficient to measure the highest potential voltage expected to be found inside the equipment being serviced.
	After servicing, check equipment with a multimeter or appropriate device to ensure it is grounded before reconnecting to the power source.

Safety Factors of electric wiring

The function of wiring safety codes is to give technical, performance and material standards that would allow proper use of the electrical energy. Materials required for wiring a building depend on factors like rating of the circuit, type of occupancy of the building, type of electrical system, national and local regulations and conditions in which the wiring must operate. The design and planning of an electrical wiring installation involve consideration of all prevailing conditions such as the type of supply, envisaged load, earthing arrangements, safety aspects and energy conservation. It is essential that adequate provision is made for all services such as lighting, power requirement for A/C, fridge and kitchen heating. Proper planning will prevent the householder from relying on the use of long flexible cables and multi-plug adopters which are dangerous and not recommended.

Estimation of load requirement

All conductors and switches and other accessories should be having a rating such that they are not exceeded under any circumstance of use. This may be calculated knowing the rating(W) of the lights fans and equipments connected. The size of the conductor of the circuit should be chosen so as to permit only minimum voltage drop form the inlet to any point in the installation. In each circuit or sub-circuit the fuse shall be such as to match the cable rating to ensure desired protection.

Installation

In the case of concealed wiring, installation should begin immediately on completion of the main structural work and before finishing works such as plastering . In the case of surface wiring, it can be carried out after plastering . Generally, installation should not start before the building is reasonably weatherproof. However, where electrical wiring is to be concealed within the structure as in a RCC building, the necessary conduits or ducts shall be positioned firmly and tied to the reinforcement before concreting. When shutters are removed after concreting, the conduit ends shall be sealed by caps to protect them from getting blocked. All conduit openings and junction box openings should be protected against entry of muck or mortar during construction.

Conductors for all internal wiring may be of copper. The conductor for final sub-circuit for fan and light wiring should be not less than 1.5 mm2 of copper and for power cable not less than 4.0 mm2 of copper. In existing buildings it is advisable to replace wiring which is more than 30 years old as the insulation in it would have deteriorated. This will be in a state to cause failure leading to short circuit on the slightest of either mechanical or electrical disturbances.

Accidental shock

Earthing is required to by-pass the over-rated current caused due to fluctuation in circuit parameters such as phase frequency and line voltage etc., to save human life and electrical assets from short circuits.

Fuse is a conditional switch having fuse wire of low melting point required to save the electrical network in case of overloads and short circuits. Short circuit occurs due to accidental contact of phase with another phase or phase with neutral or phase with earth wire.

Use of RCCB/ ELCB (Residual current circuit breaker/ Earth Leakage circuit breaker) prevents the accidental shocks and also keeps a check on the earthing system of the house. In case of leakage of very small current in milli-amperes would trip the circuit and prevent the mishap.

Concealed wiring

Concealed wiring is safe for the building as long as it is properly placed and joints are properly covered. There should be tap holes for checking the wiring at suitable intervals. The wiring should not be too close to the slab and also from the wet areas in the building. The wiring should not be exposed to external cracks in the walls. While concealing and embedding inserts into a structural member care should be exercised to see that the member is not made weaker. A 6 inch switch box cannot be inserted into a 9 inch column.

Thus the benefits of greater personal and equipment safety, reliability, current load capacity, discharge path for short circuits, fault current/surge protection, stable earth values, low resistance, longer life, and low cost maintenance can all be achieved by proper planning and installation of electric wiring.

Safety instructions

•Always buy electrical items that carry the ISI mark

•Identify locations for switchboards in advance so that they will not be an obstruction when the room is being decorated

•Proper earthing should be done for the entire house

•Each power board should have a separate fuse

•Registered electrical contractors should be engaged to carry out the electrical work

•Consumption of electricity should be need based. Try to save electricity as much as possible

•The entire network should be designed to avoid unnecessary or excess power loss during transmission

How does AVR of electric generators work?

The function of the AVR is to automatically regulate the voltage of generators. As a load on a generator increases its terminal voltage tends to droop. The AVR senses the drop in terminal voltage by measuring the generator voltage and boosts up the excitation to the field of the generator to maintain the terminal voltage at the set level. Similarly as the load on the generator falls, the terminal voltage is maintained by the AVR by reducing the excitation to the field. The AVR also measures the Generator stator current. 
There are various types of AVR with lots of features/limiters like power factor limiter, stator capacitive current limiter, MVAR limiter etc. But basically, all function by controlling the excitation of the field of the generator based on the sensing of the Generator terminal voltage and stator currents.

Cleaning with Vinegar

Windows & Walls

Streakless windows: 
Window cleaning with vinegar will make your windows gleam and will not leave the usual film or streaks on the glass. Mix equal parts of white distilled vinegar and warm water. Dry with a soft cloth.

Washing woodwork:
You can ease the job of washing painted walls, woodwork and Venetian blinds by using a mixture of 1 cup ammonia, ½ cup white distilled vinegar and ¼ cup baking soda with 1 gallon of warm water. Wipe this solution over walls or blinds with a sponge or cloth and rinse with clear water. Dirt and grime comes off easily and the solution will not dull the painted finish or leave streaks.

Water or alcohol marks on wood:
Stubborn rings resulting from wet glasses being placed on wood furniture may be removed by rubbing with a mixture of equal parts of white distilled vinegar and olive oil. Rub with the grain and polish for the best results.

Kitchen

Garbage disposal cleaner:
Garbage disposal cleaning with vinegar cubes keeps disposals clean and odor free.  Vinegar cubes are made by filling an ice tray with a mixture of 1 cup of vinegar and enough water to fill the ice tray and then freezing it. Run the mixture through the disposal, and then flush it with cold water for a minute or so.

Coffee maker cleaner (automatic):
White distilled vinegar can help to dissolve mineral deposits that collect in automatic drip coffee makers from hard water. Fill the reservoir with white distilled vinegar and run it through a brewing cycle. Rinse thoroughly with water when the cycle is finished. (Be sure to check the owner’s manual for specific instructions.)

Clean the microwave:
Boil a solution of 1/4 cup of white distilled vinegar and 1 cup of water in the microwave. Will loosen splattered on food and deodorize.

Deodorize the kitchen drain:
Pour a cup of white distilled vinegar down the drain once a week. Let stand 30 minutes and then flush with cold water.

Clean the refrigerator:
Wash with a solution of equal parts water and white distilled vinegar.

Clean and disinfect wood cutting boards:
Wipe with full strength white distilled vinegar.

Brass polish:
Cleaning with vinegar helps your brass, copper and pewter to shine. Dissolve 1 teaspoon of salt in 1 cup of white distilled vinegar and stir in flour until it becomes a paste. Apply paste to the metals and let it stand for about 15 minutes. Rinse with clean warm water and polish until dry.

Ant deterrent:
Ant invasions can sometimes be deterred by washing counter tops, cabinets and floors with white distilled vinegar.

Getting Rid of Fruit Flies/Gnats in Your Kitchen
Place a bowl filled with ½ quart water, 2 Tbsp. sugar, 2 Tbsp. apple cider vinegar and a couple of drops of dish soap to attract the fruit flies.  Always eliminate the source of attraction, i.e., ripened produce.

Cleaning Stainless Steel AppliancesCleaning with vinegar makes it easier to remove streaks from stainless steel appliances. Apply vinegar with a soft cloth.  Try in an inconspicuous place first.

Cleaner Dishes and GlassesPour 1 ½ cup to 2 cups white distilled vinegar in the bottom of dishwasher, along with regular dishwasher soap.  Wash full cycle. 

Remove Refrigerator SmellsPlace 1 cup apple cider vinegar in a glass and set in refrigerator.  Within 2 days, any smell is gone!

Bathroom

Bathtub film:
Bathtub film can be removed by wiping with white distilled vinegar and then with soda. Rinse clean with water.

Shower doors:
Rub down shower doors with a sponge soaked in white distilled vinegar to remove soap residue.

Toilet bowl cleaner:
Stubborn stains can be removed from the toilet by cleaning with white distilled vinegar and brushing vigorously. The bowl may be deodorized by adding 3 cups of white distilled vinegar. Allow it to remain for a half hour, then flush.

Unclog the showerhead:
Corrosion may be removed from showerheads or faucets by soaking them in white distilled vinegar overnight. This may be easily accomplished by saturating a terry cloth towel in vinegar and wrapping it around the showerhead or faucet.

Lawn/Garden

Kill grass:
To kill grass on sidewalks and driveways, pour full strength white distilled vinegar on it.

Kill weeds:
Spray white distilled vinegar full strength on tops of weeds. Reapply on any new growth until plants have starved.

Increase soil acidity:
In hard water areas, add a cup of vinegar to a gallon of tap water for watering acid loving plants like rhododendrons, gardenias or azaleas. The vinegar will release iron in the soil for the plants to use.

Neutralize garden lime:
Rinse your hands liberally with white distilled vinegar after working with garden lime to avoid rough and flaking skin. Clean pots before repotting, rinse with vinegar to remove excess lime.

Keep Flowers LongerKeep flowers fresh longer.  Add 2 tablespoons sugar and 2 tablespoons white vinegar in a 1-quart vase of water.  Trim stems and change water every five days.

Plant Nutrients
Mix vinegar and water in a ratio of 1:8.  Mix a separate solution of sugar and water in a mixture of 1:8.  Combine the vinegar and sugar mixtures.  Add to plant as long as needed. 

Pets

Pest fighter:
A teaspoon of white distilled vinegar for each quart bowl of drinking water helps keep your pet free of fleas and ticks. The ratio of one teaspoon to one quart is for a forty-pound animal.

Pet accident:
Test the color fastness of the carpet with white distilled vinegar in an inconspicuous place. Then sprinkle distilled vinegar over the fresh pet accident. Wait a few minutes and sponge from the center outward. Blot up with a dry cloth. This procedure may need to be repeated for stubborn stains.

Get Rid of Odor on a Smelly Dog
Wet the dog down with fresh water.  Use a mixture of 1 cup white distilled vinegar and 2 gallons water.  Saturate the dog’s coat with this solution.  Dry the dog off without rinsing the solution.  The smell will be gone!

Other

Bumper stickers:
To remove bumper sticker residue, try cleaning with vinegar. Wipe the surface repeatedly with white distilled vinegar until it is soaked. In a few minutes, it should peel off easily. Test on a small invisible area of the car to ensure there will be no damage to the paint.

Paintbrush softener:
Soak the paintbrush in hot white distilled vinegar, and then wash out with warm, sudsy water.

Cleaning the Radiator VentTurn down the thermostat.  Unscrew the air vent, soak it in vinegar to clean it, then turn the thermostat all the way up.  After a few minutes, you'll hear a hissing sound followed by a little bit of water spurting out.  Finally, steam will start exiting that hole.  Turn off the radiator valve and replace the vent.  It should be straight up and hand tight.  You should not need or use a wrench.

Frosted windows:
For those rare winter mornings when there is frost on the car, wipe the windows the night before with a solution of one part water to three parts white distilled vinegar.  They won’t frost over.

Furniture
Mix olive oil and vinegar in a one-to-one ratio and polish with a soft cloth.  Try in an inconspicuous place first.

Cleaning Leather Shoes
Make a solution of one part water to one part white vinegar, and use it sparingly on the shoes. Dip a cloth into the solution, and dab it over the salt-streaked parts of your shoes.
May have to repeat the cleaning a few times before all the salt is removed.  Salt actually can damage leather, so it's best to clean shoes as quickly as possible. Don't let the salt stains build up.

FireplacesWash fireplaces with a 50/50 ratio of water and vinegar to remove the blackened soot on glass front doors. If the doors have a spring-loaded clip, remove it, then take out the doors.

Lay them flat on newspapers, spray with the vinegar/water solution and soak.  Wipe it off with newspaper.

Cleaner for Gold Jewelry (Winner of June 2007 Vinegar Online Use Contest)Use one cup apple cider vinegar.  Submerge solid gold jewelry item in vinegar for 15 minutes.  Remove and dry with cloth. 

Remove Lime Stains from CarPour a small amount of white vinegar on a clean cloth.  Gently rub the area of lime staining with the cloth until the stain is gone.  Test a small are first to ensure no discoloration.

Worn DVDs:
If you have a worn DVD that has begun to stick or suffers from the occasional freeze-frame, wipe it down with white distilled vinegar applied to a soft cloth.  Ensure the DVD is completely dry before re-inserting in the DVD player.  (Note:  This only works on DVDs that are scratched of dirty through normal wear.)

Laundry Hints

Wine stains:
Spots caused by wine can be removed from 100 percent cotton, cotton polyester and permanent press fabrics if done so within 24 hours. To do it, sponge white distilled vinegar directly onto the stain and rub away the spots. Then clean according to the directions on the manufacturer's care tag.

Freshen baby clothes:
The addition of 1 cup of white distilled vinegar to each load of baby clothes during the rinse cycle will naturally break down uric acid and soapy residue leaving the clothes soft and fresh.

Clothes washing magic:
Clothes will rinse better if 1 cup of white distilled vinegar is added to the last rinse water. The acid in vinegar is too mild to harm fabrics, but strong enough to dissolve the alkalies in soaps and detergents.

Blanket renewal:
Cotton and wool blankets become soft, fluffy and free of soap odor if 2 cups of white distilled vinegar are added to the rinse cycle of the wash.

Deodorant stains:
Deodorant and antiperspirant stains may be removed from clothing by lightly rubbing with white distilled vinegar and laundering as usual.

Hole removal:
After a hem or seam is removed, there are often unsightly holes left in the fabric. These holes can be removed by placing a cloth, moistened with white distilled vinegar, under the fabric and ironing.

Keeping colors fast:
To hold colors in fabrics, which tend to run, soak them for a few minutes in white distilled vinegar before washing.

Leather cleaning:
Leather articles can be cleaned with a mixture of white distilled vinegar and linseed oil. Rub the mixture into the leather and then polish with a soft cloth.

Scorch marks: Lightly rub white distilled vinegar on fabric that has been slightly scorched. Wipe with a clean cloth.

Setting colors:
When you are color dyeing, add about a cupful of white distilled vinegar to the last rinse water to help set the color.

Shower curtains:
Add 1 cup of white distilled vinegar to the rinse water when you launder your shower curtain.  Do not spin dry or wash out.  Just hang immediately to dry.

Unclog steam iron:
Pour equal amounts of white distilled vinegar and water into the iron's water chamber. Turn to steam and leave the iron on for 5 minutes in an upright position. Then unplug and allow to cool. Any loose particles should come out when you empty the water.

Clean a scorched iron plate:
Heat equal parts white distilled vinegar and salt in a small pan. Rub solution on the cooled iron surface to remove dark or burned stains.

Cleaning Vintage LaceSoak the lace in cold water, rinsing it several times.  Next, hand-wash the lace gently with a wool detergent, such as Woolite.  If rust spots are a problem, try removing them with a mixture of white vinegar and hot water.

Food Preparation

Getting the last drops:
When you can’t get the last bit of mayonnaise or salad dressing out of the jar, try dribbling a little of your favorite vinegar into it, put the cap on tightly and shake well. You’ll be amazed at how much you’ve been wasting.

Cooking fish:
Try soaking fish in vinegar and water before cooking it. It will be sweeter, more tender and hold its shape better. When boiling or poaching fish, a tablespoon of vinegar added to the water will keep it from crumbling so easily.

Cake icing:
Cake icing can be prevented from becoming sugary if a little vinegar is added to the ingredients before cooking. The same is true when making homemade candy.

Boiling eggs:
When boiling an egg and it’s cracked, a little vinegar in the water will keep the white from running out.

Keeping potatoes white:
A teaspoon of white distilled or cider vinegar added to the water in which you boil potatoes will keep them nice and white. You can keep peeled potatoes from turning dark by covering them with water and adding 2 teaspoons of vinegar.

Freshen vegetables:
Freshen up slightly wilted vegetables by soaking them in cold water and vinegar.

Fruit and vegetable wash:
Add 2 tablespoons white distilled vinegar to 1 pint water and use to wash fresh fruits and vegetables, then rinse thoroughly.  Research has shown that vinegar helps kill bacteria on fruits and vegetables.

Frying doughnuts:
Before frying doughnuts, add ½ teaspoon of vinegar to hot oil to prevent doughnuts soaking up extra grease.  Use caution when adding the vinegar to the hot oil. 

Flavor booster:
Perk up a can of soup, gravy or sauce with a teaspoon of your favorite specialty vinegar. It adds flavor and taster fresher.

Meat tenderizer:
As a tenderizer for tough meat or game, make a marinade in the proportion of half a cup of your favorite vinegar to a cup of heated liquid, such as bouillon; or for steak, you may prefer to a mix of vinegar and oil, rubbed in well and allowed to stand for two hours.

Fruit stains:
Remove fruit or berry stains from your hands by cleaning them with vinegar.

Fresh lunch box:
It is easy to take out the heavy stale smell often found in lunch boxes. Dampen a piece of fresh bread with white distilled vinegar and leave it in the lunch box overnight.

Get rid of cooking smells:
Let simmer a small pot of vinegar and water solution.

Fluffy Egg Whites
Soak a paper towel with 1-2 Tablespoons of white distilled vinegar.  Wipe mixing bowl and beaters or whisk with the vinegar-soaked paper towel, then dry with a cloth or paper towel prior to whipping egg whites. 

Fluffier RiceFor fluffier and great tasting rice, add a teaspoon of white distilled vinegar to the boiling water before adding rice.  Rice will be easier to spoon and less sticky. 

Health

Relief from Heartburn
For relief of heartburn or acid indigestion, take one or two tablespoons of balsamic vinegar.

Continuous Positive Airway Pressure (CPAP) Machine for Sleep Apnea:
To clean the calcium deposit of the humidifier reservoir, heat 450 ml (1 ¾ cups) of vinegar in the microwave for 2 minutes. Pour vinegar into reservoir and replace cap. Let sit for 1 hour. Remove vinegar. Reservoir should be clean and calcium free. Contact manufacturer before cleaning with this method or review manufacturer’s directions.

Soothe a bee or jellyfish sting:
Douse with vinegar. It will soothe irritation and relieve itching.

Relieve sunburn:
Lightly rub white distilled or cider vinegar on skin. Reapply as needed.

Relieve dry and itchy skin:
Add 2 tablespoons of vinegar to your bath water.

Fight dandruff:
After shampooing, rinse with a solution of ½ cup vinegar and 2 cups of warm water.

Soothe a sore throat:
Put a teaspoon of vinegar in a glass of water. Gargle, then swallow. For another great gargle: 1 cup hot water, 2 tablespoons honey, 1 teaspoon vinegar, gargle then drink.

Treat sinus infections and chest colds:
Add 1/4 cup or more vinegar to the vaporizer. (Be sure to check vaporizer instructions for additional water measurement.)

Skin burns: Apply ice-cold vinegar right away for fast relief. Will prevent burn blisters.

Chest congestion:
To clear up respiratory congestion, inhale a vapor mist from steaming pot containing water and several spoonfuls of vinegar.

Toenail fungus:
Soak toes in a solution of vinegar and water, using 1 part vinegar to 2 parts water, 15 minutes per day.

Arthritis ReliefMix a teaspoon of half apple cider vinegar, half honey in a glass of water with a teaspoon of orange flavored Knox gelatin.

Lessen Morning SicknessDrink some apple cider vinegar in water, with honey added.  This concoction can help calm a queasy stomach.

Stop ItchingApply a paste made from vinegar and cornstarch.  Keep on until itch disappears. 

Cleaning Heavily Soiled HandsMoisten cornmeal with apple cider vinegar.  Scrub hands, rinse in cold water and pat dry. 

Soft FeetCombine 1 cup white distilled vinegar to 2 gallons warm water.  Soak feet for 45 minutes then use a pumice stone or file to remove dead skin from heels and callused areas of feet.

Wart RemoverMix lukewarm/warm water with a cup of white distilled vinegar.  Immerse area with wart and soak 20 minutes everyday until wart disappears. 

Bug SprayCombine equal amounts of water, white distilled vinegar and liquid dish soap in a spray bottle.  Use on skin, as needed. 

Kids Stuff

Coloring Easter eggs:
Mix 1 teaspoon of vinegar with each ½ cup of hot water, then add food coloring. (Check egg-coloring booklets or food dye box for specific directions.) Vinegar keeps the food dyes bright and prevents streaky, uneven colors.

Making naked eggs:
Place eggs in a container so the eggs are not touching. Add enough vinegar to cover the eggs. Cover the container, put in the refrigerator and let the eggs sit in the vinegar for 24 hours. Use a large spoon to scoop the eggs out of the container. Be careful since the eggshell has been dissolving, the egg membrane may be the only thing holding the egg together. Carefully dump out the vinegar. Put the eggs back in the container and cover them with fresh vinegar. Leave the eggs in the refrigerator for another 24 hours. Scoop the eggs out again and rinse them carefully. If any of the membranes have broken, throw those eggs away. When you’re done, you’ll have an egg without a shell.

How to build a volcano: 
First, make the “cone” of the volcano. Mix 6 cups flour, 2 cups salt, 4 tablespoons cooking oil and 2 cups of water. The resulting mixture should be smooth and firm (more water may be added if needed). Stand a soda bottle in a baking pan and mold the dough around it into a volcano shape. Do not cover the hole or drop dough into it. Fill the bottle most of the way full with warm water and a bit of red food color (can be done before sculpting if you do not take so long that the water gets cold). Add 6 drops of detergent to the bottle contents. Add 2 tablespoons baking soda to the liquid. Slowly pour vinegar into the bottle. Watch out – eruption time!

Berry Ink & Quill Pens

Berry ink ingredients:
½ C. Ripe berries (blueberries, cherries, blackberries, strawberries, elderberries, raspberries, etc.)
½ Tsp. Vinegar
½ Tsp. Salt

Fill a strainer with the berries and hold it over a bowl. Using the rounded back of a wooden spoon, crush the berries against the strainer so that the berry juice strains into the bowl. Keep adding berries until most of their juice has been strained out and only pulp remains. Add the salt and vinegar to the berry juice. The vinegar helps the ink retain its color and the salt keeps it from getting too moldy. If the berry ink is too thick, add a tablespoon of water. Store in a baby food jar. Only make a small amount of berry ink at a time and, when not in use, keep it tightly covered.

Quill pen ingredients:
A large feather (find your own or purchase one from a craft store)
Craft knife
Paper
Berry ink
Paper towels

Use a craft knife to cut the tip of the feather at an angle. Carefully, cut a slit in the tip. Dip the feather into the berry ink. Dab the end on a paper towel. Repeat as needed. Now, write your masterpiece just like the pioneers did!