A former member here had about 40 minutes of recorded footage after taking SN before she ctb. Here's a couple examples of low dose SN deaths.
Tablespoon
"A 17-year-old female reportedly drank approximately one tablespoon of sodium nitrite in a self-harm attempt. The patient was hypotensive and cyanotic upon EMS arrival. The patient decompensated rapidly into a bradycardic arrest during transport despite intubation, push-dose epinephrine, and intravenous fluid resuscitation. In the Emergency Department (ED), she received methylene blue and packed red cells but could not be resuscitated despite a prolonged effort."
For this one, I suspect the girl may have been "trying it out" and realized it was the real deal and called for help. No one should be messing around with taking sips of this stuff.
2,6 grams
The mechanism of death by sodium nitrite toxicity is severe hypoxia. [7], [8] The estimated lethal dose of sodium nitrite in adults is about 2.6 g [11] but some cases are reported in scientific literature of survival after ingestion of higher amounts [1], [12].