Black bears are potentially dangerous but I would disagree with the statement that "black bears have killed many" understanding that we could debate what "many" means. Best I can tell from internet sources it happens about once a year in the entire US. But keep in mind that there are thousands more black bears that are common throughout much of the US; whereas grizzly are present in a tiny fraction of the northwest. I don't fear either simply because the probability of being attacked is way less than countless other dangers.