Both 5GHz and 2.4GHz WiFi are 100% safe for human, the signal does not harm in any way.
It is perfectly safe.
Term “radiation” is often used to scare people. Let’s get it straight. There are two factors – frequency and intensity. Frequency has a far larger effect on how damaging radiation is. Wi-Fi and other radio communications use a very low frequency – far below visible light.
Radiation that actually causes issues, could potentially cause cancer, etc., is usually ionizing radiation. It has a very high frequency and can cause mutations in DNA, possibly leading to cancer (more info on that process). The frequency required to be ionizing? At least 1,000,000 GHz. That is literally a 500,000 times higher frequency than what Wi-Fi transmits on, 2.4 GHz or 5 GHz. Non-ionizing radiation, which Wi-Fi falls under, does little more than transfer heat.
Did you know light is also EM radiation? Yup. In fact, light (~500,000 GHz on the near-infrared side, ~750,000 GHz near-ultraviolet) is much closer to ionizing radiation than Wi-Fi. Sunlight actually contains some ionizing radiation (UVB, UVC – UVA can also cause DNA damage, but it’s not in the same way). But you’re not going to hide in your house for the rest of your life, are you?
Apart from frequency, there is intensity. Non-ionizing radiation can also be damaging – but this really only applies to higher intensities. And ionizing radiation is not always dangerous – our bodies can cope with lower intensities, which is why we don’t all die in the sun (vampires are another matter). Wi-Fi has a transmitting power usually far under 1 Watt (I’ve seen figures for 200 mW). And most of that energy never reaches you – by the inverse square law, you only get about 1/distance squared of that. In layman’s terms – the energy spreads equally in all directions. 10 meters away? 1/100 * 200 mW = 2 mW. That’s nothing.
Microwave ovens (which operate on a similar frequency as Wi-Fi) transmit ~1000 Watts, and it’s highly focused inside that metal box. Only maybe 1 Watt can be released through the shielding, and even that is considered perfectly safe. To put all this in perspective, sunlight (which is a higher frequency, and therefore more energetic) is about 1000 Watts per square meter when it hits the ground, half of which is visible light or higher.