[Flycatcher]

Danger to humans of rattlesnakes in North America (my informed ranking):

#1 Eastern Diamondback

#2 Mojave Rattlesnake

#3 Western Diamondback

#4 Southern Pacific Rattlesnake

#5 Northern Pacific Rattlesnake

This was a Southern Pacific snake. Formidable.

[AZJeep]

I have seen several Western Diamondbacks from safe distance, but I had very scary close encounter with Arizona Black Rattlesnake (Crotalus cerberus). Rattling and loudly hissing, just next to me.
That one is smaller (< 3ft), little bit less aggressive and little bit less poisonous.
It scared a s**t out of me anyway!
I was far away from civilization in AZ woods, no phone signal.
I do not know if I could make it out of there alive?