Thanks to food safety programs, most of us are well-schooled in the preparation of safe food. We know that we should wash our hands before cooking, that meat must be cooked to a safe temperature and that we should, according to the FDA, “wash cutting boards, dishes, and utensils (including knives), and countertops with soap and hot water after [emphasis in the original [emphasis added]] they come in contact with raw meat, poultry or seafood.”

Although such food safety steps are largely based on sound science and reason, it’s concerning that the federal government does not consider poultry or seafood to be meat. Anyway, we’ve built a structure of regulations to protect ourselves from contamination. But, like the sanitation triangle, it all comes crashing down as soon as one of the supports is knocked out.

Let’s test our familiarity with food safety by taking a look at an example of a chef cooking a simple dish. See if you can spot any instances of cross contamination.

  1. The chef washes his hands thoroughly.
  2. He grabs a fresh, uncooked chicken breast from the package and places it on a clean cutting board.
  3. Using a clean, sharp knife, the chef fillets the chicken boob.
  4. The chef washes his hands thoroughly.
  5. Using a clean pair of tongs, he picks up the fillets and places them in a clean, preheated frying pan.
  6. He then washes his hands, the cutting board, the knife and the countertop.
  7. Using the tongs, the chef flips the meat over to ensure even cooking.
  8. After measuring the internal temperature of the meat using a food thermometer, the chef concludes that the meat is safe to consume.
  9. He removes the chicken from the frying pan with the tongs and places the cooked meat on a clean plate.
  10. The chef washes his hands, the frying pan and the tongs, then serves the dish.

If you said that the contamination occurs at steps 8 and 10, when the chef failed to wash the thermometer, then you’re not correct. Since the thermometer measured a safe cooking temperature, we know that there’s no way that it could be contaminated. Of course, it’s not the most hygienic decision to leave the thermometer uncleaned, as it may eventually pose a problem, but there is no immediate threat of contamination.

The thermometer, though it came into contact with raw meat, endured the cooking process and was raised to a temperature that rendered it safe to consume (if it weren’t a thermometer). However, between transferring the raw chicken to the frying pan, flipping the meat and placing it on the plate, the tongs underwent no such process.

The infraction occurred when our chef, like nearly every cook across the globe, used the same utensil to handle the meat throughout the cooking process in steps 5, 7 and 9. As mentioned earlier, food safety regulations make it clear that we should wash our hands, surfaces and utensils after making contact with uncooked meat, but for some reason we fail to apply this to the tool we use to move our meat.

It’s not clear why we don’t seem concerned about our tongs and spatulas. Perhaps we do secretly recognize the threat, but we subconsciously concede that it would be far too annoying to wash the tool after each time we transfer, rotate, flip, poke, prod and peer underneath our meat. Or maybe, as with bathroom sanitation, we just know that we’re probably going to miss a step somewhere along the way.


We’ve all been there. One moment we’re minding our own business, travelling down the highway on our way to satisfy some temporary urge. Suddenly we notice a vehicle appear to our right, and he wants to merge into our lane.  We know that the merging driver wants to enter our lane, but he has limited time and space to decide exactly how to proceed. Now we’re in a precarious situation with a number of potentially fatal possibilities. Here’s a series of images below depict a common outcome:

Figure 1. The first image shows a dark sedan reaching the merge lane, while a white pickup truck is proceeding in the right lane.

Figure 2. Noticing the sedan, the driver of the pickup begins to move into the left lane.

Figure 3. Realizing that the pickup is moving into the far lane, the driver of the sedan begins to merge.

Figure 4. The sedan continues merge uninhibited now that the pickup is out of the way.

Figure 5. The sedan’s merge is nearly complete.

Figure 6. The merge is now complete. Both vehicles continue travelling safely down the highway.

Most find the events detailed above fairly unremarkable. In fact, they might even say that it was a great example of a driver etiquette and caution on the part of the pickup driver, but the truth is nothing of the sort. Noticing that the sedan was travelling alongside him, the driver of the pickup was faced with three basic options:

  1. Slow down and let the sedan merge in front of him.
  2. Accelerate in order to allow the sedan to merge behind him.
  3. Continue at the same speed.

The driver of the sedan also has three similar options:

  1. Slow down speed and attempt to merge behind the pickup.
  2. Accelerate in order to merge ahead of the pickup.
  3. Continue to merge at the same speed.

It’s kind of like playing a game rock-paper-scissors, with each driver trying to anticipate the other’s next move. Here’s a table showing the possible results:

Pickup Choice Sedan Choice
Slow down Accelerate Continue at Same Speed
Slow Down  Crash  No crash  No crash
Accelerate  No crash  Crash  No crash
Continue at Same Speed  No crash  No crash  Crash

As we can see, 3 of the 9 possibilities result in a crash, which is alarming. This is why drivers often choose the secret fourth option: moving into another lane. Of course, this is only possible when there’s another lane in which to move, but doing so circumvents the merging problem entirely. However, it has a serious drawback.

When the pickup driver decides to move over and allow the sedan to merge, he is entering into a lane that could already have traffic in it. This creates another table of possibilities based on the number and speed of vehicles in the left lane. If there is a vehicle in the left lane, then this vehicle and the pickup are now in a nearly identical situation as were the pickup and the sedan. And of course, many highways have more than two lanes, which means that should the driver in the left lane choose to move over, it could result in a third encounter.

The problem here is not that moving out of the right lane to accommodate merging traffic is inherently unsafe, but that it attempts to resolve a crisis by merely shifting the problem to another party. According to traffic regulations, it is the duty of the merging vehicle to match the speed of highway traffic and select a position in which to merge. In the aforementioned case, the pickup driver alleviates the driver of the sedan from this responsibility by taking it upon himself to merge into the left lane. While this act may seem prudent and selfless, it actually has some serious consequences. Here are a few things wrong with this behavior:

  1. It forces additional vehicles into a merging scenario, each of which could result in a crash.
  2. It slows down traffic in the passing lane.
  3. It fosters an expectation for highway traffic to yield to merging drivers.

The third point is more difficult to measure, but its effects are likely the most serious. By yielding to merging traffic, the rules of the road are obscured, and merging drivers come to mistakenly believe that they have the right-of-way. This, in turn, results in a greater number of dangerous merging scenarios, which means more crashes. The whole point of traffic laws like those governing highway merging is to clearly indicate which party has priority, so that we don’t feel like we’re playing rock-paper-scissors.

Now changing lanes to make room for merging traffic is not always unwise. If done with caution and well in advance of the merging lane, it’s a great way to avoid a potentially hazardous situation. Just make sure you’re not merging to avoid merging.