Graduation Year


Document Type




Degree Name

Doctor of Philosophy (Ph.D.)

Degree Granting Department

Civil and Environmental Engineering

Major Professor

Daniel Yeh, Ph.D.

Committee Member

Xiaopeng Li, Ph.D.

Committee Member

Kingsley Reeves, Ph.D.

Committee Member

Christian Wells, Ph.D.

Committee Member

Bob Rubin, Ph.D.


Failure, RAMS Framework, Risk Assessment, Risk Ranking


In established industry sectors, Reliability, Availability, Maintainability, and Safety (RAMS) risk assessments are normally used to compare the risks associated with different technologies on process units. Sanitation solutions are split into traditional wastewater treatment which is centralized treatment and can be classified as an established industry, and decentralized treatment such as pit latrines and septic tank systems which are on much smaller scales. Also they can be classified as non-conventional methods such as reinvented advanced decentralized non-sewered sanitation solution techniques exist mainly in two forms as “Single-User Reinvented Toilet (SURT)” systems or “Multiple-User Reinvented Toilet (MURT)” systems. Advanced decentralized non-sewered sanitation systems include prefabricated advanced onsite solutions, these types of sanitation technologies aim to meet global sanitation challenges such as those stated in the United Nations Sustainable Development Goals (UN SDG) and promoted by the creation of the ISO 30500 standard for decentralized non-sewered sanitation systems, which focuses on the general safety and performance requirements of such systems. So, an important step for meeting the global sanitation challenge is to assess existing technologies and new emerging technologies to see if the gaps in the definition of sustainable sanitation as determined by stakeholders are bridgeable with methodologies that go beyond just the provision of sanitation. A logical methodical approach to sustainable sanitation includes the assessment of reliability, availability, maintainability, and safety (RAMS). Taking into consideration these aspects in a measurable way will help ensure that there is a robust mix of technologies, choice, competition, and affordability of options for sanitation; all of which help ensure success however it is defined. Additionally, standardization of approaches taken by different technology providers in the achievement of global sanitation ambitions will ensure a level playing field in sanitation design globally, which will enable decentralized systems to become more reliable, and more efficient.Thus, a focus on the qualitative determination of RAMS for SURTs and MURTs is due. This paper aims to define the methodology and approach required in the determination and qualification of the failure modes of decentralized sanitation systems based on RAMS analysis. This approach will be based on a RAMS risk assessment framework informed by classifying the stakeholder definition of failure. .