 ### Description

The method of Green and Wright for estimating the time of death uses rectal and environmental temperatures. It assumes that a double exponential mode adequately describes how the body cools.

= ((rectal temperature in °C at time 2) - (rectal temperature in °C at time 1)) / (time interval in hours between time 1 and time 2)

where:

• The original equation shows temperature at time 1 minus temperature at time 2, but states that G is always negative, since the latter temperature is always greater than the former.

= (((rectal temperature in °C at time 1) + (rectal temperature in °C at time 2)) / 2) - (average environmental temperature in °C)

reduced theta =

= ((rectal temperature at the time of death) - (((rectal temperature in °C at time 1) + (rectal temperature in °C at time 2)) / 2)) / ((rectal temperature in °C at time of death) - (average environmental temperature in °C))

where:

• The rectal temperature at the time of death is assumed to be 37°C.

Estimation of F

For reduced theta between 0 and 0.639, the rise in F is linear, and is approximated by the equation derived in JMP:

F =

= (1.8826 * (reduced theta)) - 0.026636

For reduced theta from 0.639 to 0.96, the rise in F is exponential, and can be approximated by the equation derived in JMP.

F =

= (317.62648 * ((reduced theta)^4)) - (926.6809 * ((reduced theta)^3)) + (1014.8223 * ((reduced theta)^2)) - (491.3695 * (reduced theta)) + 89.622192

Calculation of Time Since Death

time since death in hours =