Cover-alls are an essential part of the Personal Protection Equipment (PPE) of any nuclear power plant (NPP) worker. The color, however, is not. Workers at Chernobyl would wear white cover-alls, white mouth guards, white shoe covers, and white cloth caps because it’s the color of choice for NPP workers in the Soviet Union, now Russia and surrounding areas. But the reason for the white color is not really relevant to any safety codes or protocols. Now we can at least look at some of those safety irrelevant reasons.
The difference between dyes
One possible reason for the white may have been that it was simply a budget-friendly choice among all the other colors of cover-alls. Many power plants do have colored cover-alls, mainly to differentiate between workers that go into controlled areas and those who don’t. Bright colors are especially popular since substances that land on those colors are easier to detect. White, being one of those bright colors, is a perfectly viable option, especially if it’s more inexpensive than the other bright colors.
Oohh, and since the core of the NPP at Chernobyl contained graphite, a dark substance…
It may be tempting to think that a good reason for the white is because the reactor's moderator blocks contained graphite, and graphite would be easy to detect on white (black on white, can't get easier to detect than that, right?). However, under normal circumstances (workdays when the power plant does NOT blow up), if any of the graphite from the core gets on your clothing it's quite a bad situation and it’s far too late for you. Normal work in a NPP does not require you to come in contact with the graphite, and if it did it would spell out a severe radiation leak and, again, it would mean it's way too late for you. At this point you might start glowing, and not in the good way (not really, you wouldn’t glow, but you get the point).
White: it’s what’s available
Other possible reasons for the white clothing is that white was simply the color available and then it just stayed. Russian NPP workers mostly wear white to this day and it’s not because of any safety reason. Put yourself in the shoes of the people in charge. If you get PPE for your workers and it serves its purpose, does it really matter what color it is? If white was the color that was available, you might think to yourself, “Perfect! And hey, it’s easy to spot stuff on white, too. Double perfect!”
Info for those who are curious:
When you boil it down, NPP workers need to wear protective clothing just because if there’s a case of contamination, you can take the clothing off and not carry the radiation with you out of the plant. Most of the time a full clothing change is required to enter and exit from controlled areas, though there are times when simply putting cover-alls over your normal clothes is allowed (like if you’re not a visitor rather than a worker). Typically, NPPs will have two changing rooms a “cold” changing room for people entering a controlled area and a “warm” changing room those exiting. There are screenings and agents to inspect for contamination before entering the warm changing area. In case of contamination, you’d remove the cover-all and walk out clean. Not only does this save the people outside, but you also don’t want any radiating spec on you for longer than it has to be there.
If you are contaminated, don’t just rush out to take KI (potassium iodide) pills, more commonly known as “iodine pills.” There is a health risk to taking KI, so if it can be avoided, don’t take it. Only take KI pills under the instruction of medical professionals. The way these pills work is they by filling your thyroid gland with stable (not radioactive) iodine, therefore blocking the radioactive kind because no more iodine will fit in the gland. Out of all your organs and body parts, your thyroid is the most sensitive to radioactive iodine, so the pills help. Not so fast, though. The pills will only save your thyroid but do very little to save the rest of your body, so they’re not a cure-all against catastrophic radiation spread like that of Chernobyl. Again, only use them under the direction of professionals.