Such is my life...

I've just spent the last couple of hours dripping synthetic blood off of hammers, knives, screwdrivers, and the like onto different media (newspaper, carpet, glass, cardboard, etc) from measured distances, and using calipers to measure the diameters of the spatters. Over other labs, we have measured the effect of angle on the shape, diameter, and length of the spatters, and have made analysis of the satellite droplets from the spatter from different heights.

Just so you know: synthetic blood sucks.

It stains worse even than real blood, by virture of the red dye in it.

It doesn't coagulate, which is good. It doesn't coagulate, which is bad for the science of the study of blood.

It doesn't spread like real blood. On glass, a spatter of this fake stuff will hit, spread, and then visibly draw itself back up into a tighter drop, due to the thickener in it.

Real blood isn't a solution as this fake stuff is-- it's a suspension of solids in saline. While the specific gravity of real blood is 1.06 (almost exactly the same density of water), the viscosity is much, MUCH higher. The nature of clotting is virtually irreproducable.

But our university's Office Of Risk Management & Not Getting Sued almost nixed the entire course when they found out that our professor, a scientist and bona fide expert in the field, was planning on using real blood. So we do what we can. The good part is that we're being exposed to the degree of anomaly that can be presented, and have a constant medium. But we all take some of this with a grain of salt.

My lab partner, a young fellow who interns with an alphabet federal agency, is a pleasure to work with, though, and we find ourselves amused at inappropriate things with some regularity.