Radiation sickness is no laughing matter, and unless you understand exactly what you need to do in the event of a nuclear blast, you are likely to end up experiencing it firsthand. Thankfully, there are things we can do to avoid it. Here is what you need to know about radiation sickness:

Units you need to understand with radiation sickness

I'll mainly be using the units of roentgen. If you see me say something like 5R, that means 5 roentgen. This is a unit of measurement for calculating the dose of radiation absorbed. The lower the roentgen, the safer you are.

An area that will expose you to 300R is going to be exponentially more dangerous than a place with 0.5R.

There are other radiation units as well, though. Grays, rads, and rems all deserve mention as well. For our purposes, consider 1 roentgen, 1 rad, and 1 rem to all mean the exact same thing. A gray is worth 100 Rads.

Don't get too caught up in the numbers. Just know that the higher the number is with just about anything related to radiation, the worse off you are. The predominant exception to this would be in discussing the protection factor (PF) of a shelter. The higher the PF of a shelter, the safer the shelter is from radiation.

What is radiation sickness? 

There are different types of radiation, but you're probably familiar with the concept already of the radiation from a nuclear weapon being of the lethal variety. Though you can't see it – it's invisible – after a nearby nuclear blast, this type of lethal radiation would be all around you.

Despite being a good distance away from the mushroom cloud, despite being unharmed by the blast, fireball, or heat wave, simply being unprotected could lead to your absorbing a lethal dose of radiation. This means that just going outside to check on your garden could prove to be a deadly activity.