Alcohol Neutralization Model

Your patient claims that he only had one beer every 2 hours since 4 pm. However, his blood alcohol was .025 (which is 15 mL of alcohol) when he was brought in at 10 pm.

Is this possible?

At what time will he be sober?

I. Basic Model


Create a Blood_Alchol Stock
Flow: Breakdown
Set initial blood alcohol 6000 mL of blood - .01% is limit so, 6 mL
Set initial outflow at 1 mL/hr to be rid of alcohol after 6 hours
Graph this

Is this what you think really happens?

II. Accurate Model


Picture blood as marbles- blue are alcohol, silver is blood. The number of blue marbles we scoop out each time we scoop depends on the concentration of blue marbles.


Guess relationship of removal to concentration of alcohol.

So, draw connector from Blood_Alcohol stock to breakdown

Re-define outflow as a graph - direct upward correlation
Y-axis range 0-3 X-axis range 0=10

Predict what will happen to alcohol over time now

Run again

Define Legal Limt - seperate cicle - value of 6 mL (.01% of 6000mL of blood in the body) Define inflow, Drinking

Become graph
Y-axis range 0-5 X-axis range 0-12

Horizontal step graph

Show how to change time specs and graph range

  1. 4 mL at hour 2


  2. 4mL every other hour