Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.
Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.
Summary
This page is a quick reference for what goes in a microwave oven safely and what does not — the everyday question of whether you can put metal in the microwave, whether a plastic container is microwave safe, or whether aluminum foil is ever allowed. It covers cookware, dishes and coverings such as plastic wrap, wax paper and paper towels, and it explains why metal and some plastics cause problems: an appliance failure (sparking, damage to the oven, or in rare cases fire) as well as a food one (melted plastic or food that will not heat evenly).
The guidance here comes from the FDA and from microwave manufacturer Whirlpool's own published support pages, plus a real 2026 recall of cookware that caught fire in a microwave. For a specific dish or wrap with no microwave-safe mark, or for anything your own oven's manual says differently, follow your manual and the maker of the item — this page gives the general rule, not a guarantee for every product. It does not cover cleaning a microwave or checking its door and seal for damage; that is a separate check.
Safety
REMOVE A TWIST TIE, A STAPLE, OR A SKEWER BEFORE YOU PUT FOOD IN THE MICROWAVE.
These metal items reflect the microwave's energy. They can spark, damage the oven, or catch fire.
Necessary equipment
| Item | Note |
|---|---|
| Microwave oven instruction manual | The manual for your microwave gives the foil guidance and the container test for your model. |
| The dish or the covering you want to check | Do a check of the dish or the covering for a microwave-safe mark. |
Materials that are usually safe
Estimated 1 min to 2 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Use a dish that has a microwave-safe mark on the base or the label.<1mReport a problem with step 1, Materials that are usually safe
DO NOT PUT A METAL PAN, A METAL TRAY, OR A METAL-TRIMMED DISH IN THE MICROWAVE.
Metal reflects the microwave's energy. It can spark, damage the oven, or catch fire.
- Use glass or ceramic cookware. Do not use cookware with metal trim or a metal decoration.<1mReport a problem with step 2, Materials that are usually safe
- Remove a metal twist tie or a staple from a bag before you put the bag in the microwave.
DO NOT USE A PLASTIC CONTAINER THAT HAS NO MARK FOR MICROWAVE USE.
The heat of the food can melt the plastic.
- If a plastic container has a mark for microwave use, use the container.<1mReport a problem with step 3, Materials that are usually safe
DO NOT LET FOIL TOUCH THE CAVITY WALL, THE CEILING, OR THE FLOOR OF THE MICROWAVE.
Contact with a metal part of the oven can cause a spark and damage the oven.
- If your microwave manual allows it, use a small, flat piece of foil for shielding only.<1mReport a problem with step 4, Materials that are usually safe
- Use a small piece of foil only on a thin part of the food.
- Not every microwave allows foil. Read the manual before you use it.
Materials to avoid
Estimated under a minute
- Do not heat a baby bottle or a food jar in the microwave.<1mReport a problem with step 1, Materials to avoid
- Do not dry a paper bag, a newspaper, or another paper item in the microwave.<1mReport a problem with step 2, Materials to avoid
Coverings for food
Estimated 1 min
- If the cookware has a lid, cover the food with the lid.<1mReport a problem with step 1, Coverings for food
- If no lid is available, use wax paper, a paper towel, or microwave-safe plastic wrap.<1mReport a problem with step 2, Coverings for food
- Leave a gap at one corner of the plastic wrap so steam can escape.<1mReport a problem with step 3, Coverings for food
- Cover vegetables with a microwave-safe lid or a damp paper towel to trap steam.<1mReport a problem with step 4, Coverings for food
The container test
Estimated 1 min to 2 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Do a check of the base of the dish for a microwave-safe symbol or the words "microwave safe."<1mReport a problem with step 1, The container test
- If the dish has no mark, read the container test method in your microwave oven manual.<1mReport a problem with step 2, The container test
Recall notice
U.S. Consumer Product Safety Commission 26-537
On 11 June 2026 the CPSC announced the recall of about 86,040 Kitchen HQ brand thermal insulated bowls with detachable hinged lids, imported by HSN, Inc. The lids have metal springs that can catch fire when the bowl is used in a microwave; HSN reported 30 incidents of smoking, sparking, melting, or fire, including one with property damage. Consumers are told to stop using the bowls immediately and contact HSN for a refund. Cited here as a real, dated example of why a container with a hidden metal part should not go in a microwave, not as a guide to any current product line — check your own cookware against the recall databases separately.
Terminology
This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.
- microwave-safe
- Also called: microwave safe, microwavable, microwaveable, safe for the microwave, ok to microwave, will this melt in the microwave
- arcing
- Also called: sparking in the microwave, sparks in the microwave, blue flash in the microwave, electrical arc
- shielding
- Also called: foil shield, covering food with foil, small piece of foil in the microwave
- vent the covering
- Also called: turn back a corner, let steam out, poke a hole in the plastic wrap
When to use a professional
If a container or a covering melts, warps, or scorches in the microwave, do not use it again. Contact the microwave manufacturer if you are not sure a material is safe for your model. Contact the maker of the dish or the covering if it has no microwave-safe mark. Contact the maker too if your microwave manual gives no test. A damaged door, a damaged hinge, or a damaged seal is a separate check. This page does not cover that check.
Common questions
Can you put metal in the microwave?
No. Metal reflects microwave energy instead of letting it pass through to the food, which can create a spark (called arcing), damage the oven, and in rare cases start a fire. Whirlpool's own guidance says not to use metal cookware, bakeware, skewers, twist ties, staples, or dishes with a gold or silver trim in a microwave. In 2026 the CPSC recalled a line of insulated bowls after their metal lid springs caused smoking, sparking, melting, and fire during microwave use. If a dish has any metal part, including a hidden hinge or spring, keep it out of the microwave.
Can I put aluminum foil in the microwave?
Sometimes, but only if your own oven's instructions say so. Whirlpool's guidance allows a small, flat piece of foil to shield part of a food item on some models, but says the foil must never touch the cavity wall, ceiling, or floor, or touch another metal object. Not every microwave allows foil at all. If your instruction manual does not mention foil shielding, leave it out.
How do I know if a plastic container or plastic wrap is microwave safe?
Look at the base of the container, or the wrap's packaging, for a microwave-safe symbol or the words "microwave safe." The FDA notes that some plastic containers should not go in a microwave because the heat of the food can melt them, and that your microwave's own instructions explain how to test a container that has no label. If you cannot find a mark and your manual gives no test, glass or ceramic cookware is the safer default.
What can I cover food with in the microwave?
Whirlpool's cooking guidance lists the lid that came with the cookware as the first choice. If you do not have one, wax paper, a paper towel, or plastic wrap labeled for microwave use are the alternatives it names. If you use plastic wrap, turn back one corner so steam can escape.
Why do my vegetables spark in the microwave?
Some vegetables, including carrots and green beans, contain minerals such as iron and magnesium that can behave like tiny pieces of metal and spark inside a microwave, according to Whirlpool. It does not harm the food, but it can stop the food from heating evenly, and Whirlpool warns that a lot of arcing can damage the oven's magnetron. Cutting vegetables into smaller, even pieces and covering them with a microwave-safe lid or a damp paper towel is Whirlpool's own suggestion to reduce it.
Can I dry a paper towel or a newspaper in the microwave?
No. Whirlpool's guidance specifically says paper items, including brown paper bags and newspaper, should not be dried in a microwave oven. That is different from briefly covering food with a paper towel while it heats, which the same manufacturer lists as an acceptable covering.
Related procedures
- How to clean a microwave and check if the door and seal are damaged
- How to descale a coffee maker, and whether you can use vinegar
- How to descale a kettle, and whether vinegar is safe to use in it
- How to descale a steam iron and stop it spitting brown water
- How to fix a stand mixer that leaves flour in the bowl or hits the bowl with the beater
- How to check if something you own has been recalled
Sources
Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.
- Tier 1Microwave Ovens
- Tier 1Using Aluminum Foil and Metal in Microwave
- Tier 1What Shouldn't Be Used in a Microwave
- Tier 1Foods that May Spark - Microwave
- Tier 1Microwave Cooking Tips - Countertop Microwave
- Tier 1HSN Recalls Kitchen HQ Thermal Insulated Bowls Due to Fire Hazard
Revision history
Current version 2 · updated 2026-08-04 · next review due 2027-08-04
- v2 · 2026-08-04The twist-tie hazard named step s2, which is about choosing glass or ceramic cookware. It is not about cookware at all: no step on this page covers removing a metal fastener from food packaging, so the hazard protected a step that does not exist. Check 4 did not catch it, because it proves a hazard renders before the step it names and never asks whether the hazard is about that step. Made page-level, which renders it above every step and satisfies rule 4 for all of them.
- v1 · 2026-08-04First draft, researched from FDA and Whirlpool manufacturer documentation plus a 2026 CPSC recall of insulated bowls that caught fire in a microwave.
Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.
Comments and corrections
Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.
Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.