A quick search tells me that human hair grows at an average of 15cm per year, humans have an average of 100,000 hairs on their heads, and that the average human lives for 72 years. So the average human would have 10,800km of hair waiting for them in heaven by the time of their death. Which is a lot of hair. I'd be interested to know the mass of the hair but google is terrible and I am fed up with trying to find information that isn't just fluff.