Blood Coagulation

[beesy]

Does anyone know how long blood can be spilled before it coagulates or does it? Not on the body, but the surface.

 

[sharkeyes]

About 4-8 minutes for whole blood according to what I could find when I did a google search - I thought it would be longer....I gotta go back and see if I can find a more definitive answer!

 

[beesy]

About 4-8 minutes for whole blood according to what I could find when I did a google search - I thought it would be longer....I gotta go back and see if I can find a more definitive answer!

Ok, great! I couldn't find a time when I searched. If you find a good site, can you give me the link? And this is on a surface?

 

[sharkeyes]

The site I found it at is:
tollefsen.wustl.edu/projects/coagulation. If you search google using "blood coagulation time" it's the first site listed. I went back and looked at other sites but was unable to find anything referencing whole blood specifically on a surface - the sites listed get into the laboratory/technical clotting properties. I'll try to find a site that is specific to crime scenes and will post again if I find anything.

 

[Goody]

The site I found it at is:
tollefsen.wustl.edu/projects/coagulation. If you search google using "blood coagulation time" it's the first site listed. I went back and looked at other sites but was unable to find anything referencing whole blood specifically on a surface - the sites listed get into the laboratory/technical clotting properties. I'll try to find a site that is specific to crime scenes and will post again if I find anything.

I can't answer the question specifically, but I've heard experts testify that droplets dry on the outer edges first within minutes of exposure to the air and the the whole drop will dry within a few more minutes if it is not to thick or puddled too deeply. Puddles take longer but probably dry much more quickly than most people would imagine.