The emergency sector does have a standard like the ISO it is the HAP Standard see http://www.hapinternational.org/ this organization has many leading INGOs as members.

Secondly not having guarenteed funding is part of the problem for NGOs beucase they cannot be strategic in their approach and build sufficient capacity to egnage with long term issues if they have cycles of boom and bust around project acquisition. NGOs shoudl be accountable, but should also be equipped well to do the job.