THE PHYSICAL-PROPERTIES OF BLOOD - FORENSIC CONSIDERATIONS

An informed understanding and appreciation of blood related crime scen es is only achieved through practical experimentation of simulated blo od spatter. Because of the increasing frequency of the HIV, Hepatitis B and C viruses, the use of human blood may be hazardous for those inv olved in such experimentation. Porcine (pig) blood has been cited by s ome as a reasonable alternative, and this paper presents a comparison of the physical parameters (surface tension, viscosity and density) of ageing pig and fresh human blood, under a variety of conditions, as w ell as measurements of droplet trajectories and stain patterns. The re sults support the use of porcine blood (up to two weeks old) in repres enting the behaviour of freshly spilt human blood.