How Long Can Eggs Sit Out?

The 2-hour rule, the Salmonella risk, why eggs belong on the bottom shelf, and how to cook them safely.

We have already covered the strict rules for chicken, pizza, gravy, and milk. Today we are cracking open the science behind one of the world's most popular breakfast foods: eggs. In Canada, leaving eggs on the counter is a food safety hazard.

Why eggs are a hazardous food

Under Ontario food safety laws, potentially hazardous foods are those that provide an environment conducive to the survival, growth, and multiplication of harmful bacteria. To multiply quickly, bacteria need moisture, protein, and a neutral pH level.

Eggs are packed with moisture and protein. The pH scale measures how acidic a food is, and bacteria hate acid. Raw eggs have a pH of 6.4 to 9.0, which makes them highly neutral and slightly alkaline, meaning bacteria will happily move right in and start a family.

The Salmonella threat

The biggest threat hiding inside an egg is a pathogenic bacterium called Salmonella. Salmonella is a foodborne bacterium most commonly found in raw poultry, such as chicken and turkey, but it is also commonly found in unpasteurized milk and raw eggs.

When you eat food contaminated with live Salmonella bacteria, they pass through your stomach and into your intestines, where they begin to multiply. Within 6 to 72 hours, it causes a severe infection known as Salmonellosis. The symptoms include fever, abdominal pain, diarrhea, severe nausea, vomiting, and dehydration.

Because Salmonella is so dangerous, Ontario food premises are legally forbidden from using what the government calls Grade C or ungraded eggs. When food inspectors or chefs open a carton of eggs, they look closely at the shells. If an egg has cracks or feathers or animal feces stuck to the outside of the shell, it is automatically considered a Grade C egg. Cracked and dirty eggs pose a high risk of Salmonella contamination and must be thrown in the garbage. If a restaurant uses liquid eggs from a carton, the law requires that the eggs be pasteurized and that the packaging not be broken.

Why eggs are shelved at the bottom

Have you ever noticed that in professional kitchens, eggs are shelved separately or kept on the bottom shelf of the refrigerator? It comes down to a food safety rule called cross-contamination.

Cross-contamination happens when raw food or raw juices come into contact with safe, ready-to-eat foods. Because raw animal products, including raw meats, poultry, and eggs, carry harmful microorganisms such as Salmonella, they must be kept away from cooked foods and fresh salads.

Imagine putting a carton of eggs on the very top shelf of your fridge. If one of the eggs has a tiny crack, the raw, Salmonella-infected egg yolk could drip down onto a bowl of fresh fruit on the shelf below it. If you eat that fruit, you will get severely sick.

To prevent this, the government mandates that you refrigerate acceptable eggs as soon as you receive them and store them in their original containers. They should be placed in a cold refrigerator set to 4°C (40°F) or lower. If you keep raw eggs in their shell safely in the fridge, they have a shelf life of exactly 3 weeks.

The 2-hour rule: how long can eggs sit out?

So, you take your eggs out of the fridge to make breakfast. How long can they safely sit on the counter?

Because eggs are a highly hazardous food, the strict legal and scientific limit for how long they can sit out at room temperature is 2 hours.

Why only two hours? This strict time limit exists because of the Temperature Danger Zone, the specific temperature range between 4°C and 60°C (40°F and 140°F). When you take a cold carton of eggs out of the fridge and set it on the counter, the eggs warm up and fall right into the middle of this Danger Zone. In this warm, comfortable environment, bacteria wake up and multiply incredibly fast. If the temperature in your kitchen is warm, bacterial cells will reproduce by dividing themselves in half, doubling their numbers every 10 to 20 minutes.

If your raw eggs or a cooked egg dish has been sitting out for more than two hours, it is officially unsafe to eat. You cannot just put the eggs back in the fridge to save them, because refrigerators do not kill bacteria; cold temperatures only slow them down. After two hours in the Danger Zone, the eggs must be thrown away immediately.

Cooking eggs safely

If you have kept your eggs safely out of the Danger Zone and it is time to cook them, you must use high heat to ensure any Salmonella bacteria are completely destroyed.

According to Health Canada and Ontario guidelines, when cooking egg dishes, casseroles, or mixtures containing eggs, they must be cooked to a minimum internal temperature of 74°C (165°F). You should use a cleaned and sanitized probe thermometer to check the center of your egg dish, and the temperature must hold at 74°C (165°F) for at least 15 seconds to ensure it is perfectly safe to eat.

Final food safety quiz

Test your memory with these 5 questions, then tap to reveal the answer.

For the full guide to safe holding times for every food type, see the main how long can food sit out guide.