[Life risk and nature of SAMU: users' perspectives and implications for nursing].

The article is part of a qualitative study analisys developed in 2009 aiming at investigating the demand of emergency calls to the Emergency Mobile Attendance Service/Porto Alegre (SAMU) that classifies it as non-pertinent. The information was gathered from 16 semi-structured interviews with the subjects of that demand by utilizing as a methodological guideline the Grounded Theory. The article approaches the content of the sub-category "Entering into conflict with SAMU regulation in the evaluation of life-threatening", by focusing the divergences between the regulation and the users' perception about the operation of the service and the meaning of "life-threatening", factors implied in the construction of the non-pertinent demand. The importance of Nursing within this scenery is in its competence to perform education actions about first aid and to participate in projects among sectors which are able to intervene in situations that generate vulnerability.