Theory of Electric and Microwave Ovens: Chapter 3
Comparison of Ovens
In this module, we will discuss the difference between
A toaster, An electric oven, and A microwave oven. Skip to quiz!
Toaster Oven vs Electric Oven
Recall that ovens use electrical energy to cook the food, However, a toaster oven consists of one coil, and an electric oven has two coils. Toaster ovens are used for toasting, baking small cakes, small amounts of cookies, and other small products.
An electric oven is used for different cooking methods as the broil and bake elements have different uses. An electric oven has a wide range of cooking methods. The electric oven has racks and can serve multiple dishes simultaneously, whereas most of the toaster oven has one rack.
Toaster ovens cost less than electric ovens due to fewer features and a single coil. As electric ovens have different heating elements and require a preheating time, while in a toaster oven, no such time is required. Toaster ovens can do a single function at a time, while electric ovens can do multiple functions.
Electric Oven vs Microwave Oven
An electric oven uses electrical energy and cooks food from outside to inside. We can use a conventional oven to do many different things, such as baking, toast, grilling, and cooking. One of the other main benefits of using a conventional oven is temperature control.
Different foods cook at different speeds or require specific temperatures. A microwave oven has a wide range of heat settings from ‘Defrost’ to ‘Very High.’ A conventional oven that has a fan will also distribute heat evenly, just like a rotating plate in a microwave oven.
A microwave oven uses microwaves and cooks food from the inside, while an electric oven cooks food from outside. Microwaves cook food much faster than a conventional oven. In a microwave oven, heating is not required longer than 10 minutes.
Microwave ovens are expensive and have a high power usage than electric ovens. Electric ovens are easier to repair than microwave ovens. Electric ovens have fewer functions than microwave ovens.
A toaster and electric oven use electrical energy to heat the food but differ in heating element used. Both the ovens can cook a variety of food, but their functions increase with a convection fan. A microwave oven cooks the food from inside out, and it requires less time than the conventional ovens.
Oven’s Safety
In this module, we will discuss the Standard organizations of ovens, and Regulations provided for ovens. Skip to quiz!
International Standards
The International Electrotechnical Commission (IEC) is the organization for standards of electrical devices. IEC set the standards for the construction and usage of microwave ovens for material standards and uniformity in products.
Manufacturers of electronic radiation-emitting products sold in the United States are responsible for compliance with the federal codes. Federal Food, Drug and Cosmetic Act (FFDCA), Chapter V, Subchapter C, specifically talks about radiation control in electronic products that include ovens.
Center for Devices and Radiological Health (CDRH), the Food and Drug Administration (FDA), sets and enforces performance standards for electronic products. Manufacturers of microwave ovens are responsible for compliance with all applicable requirements of Title 21 Code of Federal Regulations (Subchapter J, Radiological Health).
Modern microwave ovens operate at a standard frequency of 2,450 Megahertz (MHz). CDRH and the FDA enforce these performance standards to ensure that radiation emissions do not cause a threat to the user’s health. The radiation limit is 5 milliwatts (mW) of microwave radiation per square centimeter.
This is measured at a distance of 2 inches from the oven surface, and this limit is very safe and cannot harm people. A Federal standard (21 CFR 1030.10) limits the amount of microwaves that can leak from an oven throughout its lifetime.
FDA tests microwave ovens in its laboratory to make sure the standard is followed. The FDA also evaluates manufacturers' radiation testing and quality control programs at their factories. Microwave ovens should follow all the limitations provided in the federal codes.
The standard also requires all ovens to have two independent interlock systems. It should stop the production of microwaves when the latch is released or the door is opened. In addition, a monitoring system stops oven operation in case one or both of the interlock systems fail.
Hazards
Most injuries related to microwave ovens are the result of
Heat-related burns from hot containers,
Overheated foods, or
Exploding liquids.
It is very rare for instances of radiation injury due to unusual circumstances or improper servicing.
Microwave radiation can heat body tissue the same way it heats food. Exposure to high levels of microwaves can cause a painful burn.
The eye’s lens is sensitive to intense heat and exposure to high levels of microwaves. Intense heat and exposure to microwaves can cause long-term problems like cataracts.
It is little cause for concern about excess microwaves leaking from ovens unless the door hinges, latch, or seals are damaged. The FDA recommends looking at the oven carefully and not using an oven if the door doesn’t close firmly or is bent, warped, or otherwise damaged.
The IEC, CDRH, and FDA set different levels of standards for oven manufacturing. The radiation limit is 5 milliwatts (mW) of microwave radiation per square centimeter at approximately 2 inches from the oven surface. Never use a damaged oven, or even the door is not closed as it may cause injuries.
Question #1: A toaster oven consists of _____ coils, and an electric oven has _____ coils.
One, two
Two, Three
Five, Ten
Six, Eight
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Answer: One, two
The oven contains a hollow chamber and provides a means of heating the chamber in a controlled way.
Question #2: Toaster ovens _____ than electric ovens due to fewer features and a single coil.
Costlier
Equal cost
Cost less
Good in features
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Answer: Cost less
Toaster ovens cost less than electric ovens due to fewer features and a single coil.
Question #3: An electric oven uses electrical energy, and a microwave oven uses ________ to cook food.
Wind energy
Light energy
Water energy
Radiation energy
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Answer: Radiation energy
An electric oven uses electrical energy, and a microwave oven uses radiation energy to cook food.
Question #4: A _______ oven has a wide range of heat settings from ‘Defrost’ to ‘Very High.’
Baking
Microwave
Open fire
Gas
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Answer: Microwave
A microwave oven has a wide range of heat settings from ‘Defrost’ to ‘Very High.’
Question #5: What should be followed while using the microwave oven?
Safety
Signal light
Steps of cooking
Turn of lights
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Answer: Safety
A microwave oven can be hazardous if not used with safety. Read the owner’s manual before using the microwave oven.
Question #6: Standard organizations for ovens are (Select all that apply)
IBAF
FDA
FIFA
CDRH
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Answer: FDA
CDRH
Standard organizations for ovens are
IEC,
FDA, and
CDRH
Question #7: Which standard organization set the standards for the construction and usage of microwave ovens for material standards and uniformity in products?
Federal Police
ASHRAE
IEC
IPC
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Answer: IEC
IEC set the standards for the construction and usage of microwave ovens for material standards and uniformity in products.
Question #8: The radiation limit is ___ milliwatts (mW) of microwave radiation per square centimeter at approximately 2 inches from the oven surface.
5
1
15
10
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Answer: 5
The radiation limit is 5 milliwatts (mW) of microwave radiation per square centimeter at approximately 2 inches from the oven surface.
Question #9: Most injuries related to microwave ovens are the result of (Select all that apply)
Heat-related burns
Closing oven door
Exploding liquids
Falling of oven
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Answer: Heat-related burns
Exploding liquids
Most injuries related to microwave ovens are the result of
Heat-related burns from hot containers,
Overheated foods, or
Exploding liquids