Microwave ovens can cook unevenly and leave "cold spots" where harmful bacteria can survive. Therefore it is important to properly stir, rotate, allow adequate standing times, and check that the minimum internal food temperatures have been reached when cooking in your microwave.

Most microwaves have hot spots, and if you eat the food directly from the oven, a few areas could be superheated and will burn you. Therefore you should always properly stir and rotate your food, and allow standing times when cooking with your microwave.

Do not use bottles or jars with narrow necks in your microwave, as pressure can build up in them causing them to explode.

Always turn off or cancel the program timer on your microwave before opening the door on your microwave. Sudden opening of the door can cause the unit's safety fuse to blow.

Frequently clean and inspect your microwave's door seal to ensure that it is closing tightly and not allowing any radiation to leak out when it is operating.

Do not use margarine or other plastic containers, foam or plastic trays, and certain plastic wraps in your microwave oven which are not made for microwave use, as when heated in your microwave they can give off chemical fumes which will get into your food (helpful accessory: microwavable containers).

Do not store anything directly on top of your microwave. This area can get hot during operation, liquid items can spill and affect how well the door seals, items can slip down and prevent the door from closing properly, and items can slip down and block air vents which can prevent proper circulation of air and heat for your microwave.

Some microwave recipes may call for shielding parts of the food, especially meats, with SMALL amounts of aluminum foil (see types, costs, and reviews of aluminum foils). This is usually acceptable as long as the area covered is less than 20% of the area of the food it is covering.

If your microwave recipe calls for a small amount of aluminum foil to cover part of the food (to keep it from cooking too fast), NEVER allow aluminum foil or metal to touch the inside cavity walls, ceiling or floor of the unit.

If you're wondering if a glass container or dish is microwave safe, here's an easy way to test it. Place a cup of water in the dish and turn on your microwave at 100% power for one minute. If the water gets hot and the dish you're testing stays cool, then it's safe to use in your microwave. But if the dish gets hot, then it contains lead or metals and should NOT be used.

Make sure everyone in your home knows which containers are microwave safe, and which are not. Keep the microwave-safe cookware separate, so that no one accidentally uses cookware that is not microwave-safe.

Never use recycled paper products in microwave ovens unless they are specifically approved for microwave use. Recycled paper towels, napkins, and waxed paper can contain metal flecks which may cause arcing or ignite. Paper products containing nylon or nylon filaments should be avoided, as they may also ignite.

Do not heat water or other liquids for more than 2 minutes in your microwave (or the time recommended by your particular manufacturer), as the liquid can superheat and under certain conditions can explode out of the cup or container when brought out of the microwave.

If you have a fire in your microwave oven, turn it off or unplug it immediately so that the fan stops and the fire is suffocated. Never open the oven door until you are absolutely certain that the fire is out. If in doubt, call the fire department.

To prevent harmful radiation from leaking out, never operate your microwave when anything is stuck in the door that prevents it from closing properly, and never operate your microwave if the door is damaged or doesn't close securely.

After cooking, lift container lids and wraps carefully and pointed away from your face and hands, so that hot steam is released safely. And similarly, be careful when opening any enclosed food where steam can be produced, such as popcorn bags, cooking pouches or food wrapped in plastic.

Always make sure that steam can escape from any covered dish in your microwave by making slits or holes in plastic wrap or loosen a lid. Otherwise, the steam can cause the food or container to explode, resulting in injury.

Do not let plastic wrap touch foods during microwaving, as the heated contact can cause chemicals to migrate into your food.

Do not cover or block any openings around your microwave, as they are important for allowing proper air and heat circulation.

Even microwave-safe cookware can become very hot in a microwave. Always use pot holders or oven mitts to remove items, to prevent burning your hands or dropping hot cookware (see types, costs, and reviews of oven mitts).

It's best to use glass containers when microwaving fatty foods, as these foods get particularly hot in a microwave. However, make sure that the glass is microwave-safe.

Some styrofoam trays (like those that meat comes from the grocery store on) have a thin strip of metal embedded in the bottom. When microwaved, the metal can burn the floor of the oven or ignite a paper towel.

Never use thin plastic storage bags, brown paper or plastic grocery bags, or newspapers in your microwave oven (helpful accessory: oven bags).

Not all plastic wrap is safe for your microwave. If you are going to use plastic wrap in your microwave, check the package to be sure that it is marked as microwave-safe.

When using the microwave to defrost meat, poultry, egg casseroles, and fish, these foods must then be completely cooked right away. Your microwave may have partially cooked part of the food, and bacteria may start to grow if the food isn't thoroughly cooked.

Be careful when heating liquids or sauces in your microwave oven. Since the containers may only feel warm rather than hot, they are sometimes handled with less caution (helpful accessory: microwavable covers). This can easily result in the splashing or spilling of scalding liquids.

If you use a meat thermometer while cooking, then make sure it is safe for use in microwave ovens.

Use a food thermometer or the oven's temperature probe to verify the food has reached a safe minimum internal temperature. Cooking times may vary because ovens vary in power and efficiency. Always allow standing time, which completes the cooking, before checking the internal temperature with a food thermometer.

When partially cooking food in the microwave oven to finish cooking on the grill or in a conventional oven, it is important to transfer the microwaved food to the other heat source immediately, to prevent bacterial growth. Never partially cook food and store it for later use.

Do not allow children to put their faces near the door of your microwave when it is operating. And just to be safe, it's best to stand at least 3 feet away from the microwave when it's operating, since if steam builds up, it can explode into their faces.

Do not leave a microwave oven unattended when microwaving popcorn, since the heat build-up can cause fires. Heat the popcorn according to the written instructions, but begin with the minimum time specified, because some microwaves can scorch popcorn in as little as two minutes.

Do not overcook potatoes, as they can dehydrate and catch fire.

Most of those burned using microwave ovens are under 5 years of age. Keep your microwave out of the reach of children, and do not permit young children to operate the oven.

Unplug your microwave oven when you are on vacation or going to be gone for extended periods. The electronic control panel has digital displays and electronic circuitry that is highly susceptible to damage caused by voltage spikes, power fluctuations, and lightning strikes.

Only use cookware (glass, ceramic containers, and all plastics) that is specifically labeled for microwave oven use (helpful accessory: microwave-safe glasswares).

Microwaved foods should be cooked to the following safe minimum internal temperatures: raw beef, pork, lamb and veal steaks, chops, and roasts to 145 °F; poultry to 165 °F; eggs and casseroles containing eggs to 160 °F; ground meats to 160 °F; and fish to 145 °F.

Use a food thermometer to check that cooked foods have reached the proper safe minimum internal temperature. When using a food thermometer place a clean food thermometer in the thickest area of the meat or poultry (not near fat or bone). For whole poultry, check the temperature in the innermost part of the thigh and wing and in the thickest part of the breast.

Carefully attend to your microwave when paper, plastic or other combustible materials are inside your microwave.

Remove any wire twist-ties or metal handles from containers before placing them in your microwave.

Remove food from packaging before defrosting. Do not use foam trays and plastic wraps because they are not heat-stable at high temperatures. Melting or warping may cause harmful chemicals to migrate into food.

When cooking foods that have a skin or membrane (such as potatoes, egg yolks, chicken livers, hot dogs, sausage, and whole vegetables) be sure to first use a fork or knife to pierce or prick them in several places to allow steam to vent to help to keep the food from exploding.

Avoid heating baby food in glass jars, even with the lid off. Make sure all infant food is thoroughly cooked. Stir food to distribute the heat evenly. Be careful to prevent scalding when warming formula. The container may feel cooler than the formula really is. Always test the formula before feeding the baby.

Avoid using a microwave when you are pregnant, especially an older model with any risk of radiation leakage around the door seals.

Before allowing older children to operate your microwave, make sure that they are instructed in its proper use, and that they are tall enough to reach the oven and handle foods safely.

Never use metal containers or cover cookware completely with aluminum foil, as microwave energy bounces off metallic materials and can cause arcing and a fire inside the oven.

Avoid food spatters by placing wax paper, paper towels or plastic wrap over the top of open cookware (helpful accessory: microwavable paper covers).

Microwaving stuffed, whole poultry is not recommended. The stuffing might not reach the temperature needed to destroy harmful bacteria. Instead cook the stuffing separately to 165 °F.

Do not attempt to fry foods in your microwave, as cooking fat in large quantities is dangerous in a microwave.

Do not cook puddings in your microwave that contain alcohol, as they may catch fire.

Do not operate your microwave if it has a damaged power cord or plug.

Do not use your microwave for home canning or sterilizing jars, as these cannot be properly controlled in a microwave.

Don't try to dry or disinfect clothing or other articles in the microwave, as this can create a fire risk.

If you have an older heart pacemaker, you should check with your doctor to see if it is a model that needs to be kept away from microwave ovens.

Never operate your microwave when it is empty, as it can cause arcing and start a fire.

Never try to repair your microwave yourself. It is a complex appliance that includes a magnetron, high voltage transformer, thermal protectors, and complicated circuits.