No, not at all. The infrared heat that these heaters emit comes off them in a light wave form, and is actually designed to warm you, it does not have any burning effect.
You will find that infrared warming devices and heaters are used by physiotherapy practitioners to warm muscles and other parts of the body to get the blood circulating without any harmful side effects.
On the other side of the light spectrum is ultraviolet. This is the kind of light and heat that is emitted by the sun and by tanning-beds and can cause skin damage / sunburn, but the infrared technology that our patio heaters use is completely safe.