How much ammonia will kill a person?

0.1 amp can kill, the human body can have as low as 300 ohms resistance. That means as little as 30 volts can supply a deadly current.

The type of current, being male or female, and personal characteristics influence this. In general smaller doses of low frequency alternating current are more deadly than DC current, but as frequency gets higher, its' effects become less than DC. 50-60mA of DC current, or 10mA of 60Hz for some will surpass the let go threshold. Breathing becomes difficult at 90mA DC and 20-30mA AC.