Page 554 - IRSEM_Main Book

Annexure: G1

Reliability, Availability, Maintainability & Safety (RAMS)

1.0 Introduction

1.1 (a) In any system output depends on input. In Railways, punctuality is an output. It
depends on how subsystems are available for service. Availability depends on
Reliability and how good/fast the maintenance (maintainability). Hence R, A, M, S
parameters are important. Punctuality is also related to equipment, failures and
Reliability in the science of failures.

(b) RAMS Assurance can help stakeholders in balancing performance requirements
and Life Cycle Cost (LCC) to improve customer satisfaction along with compliance
of National/International regulatory requirements. Many standards have
suggested that RAMS characteristics can be visualized as the Key Performance
Indicator (KPI) at System Level.

(c) RAMS concept is relatively new to the Railways as compared to other industries
such as nuclear, power, chemical, avionics, etc.

1.2 The key objective of a railway system is to achieve a defined level of rail traffic in a
given time safely. The objective can be fulfilled by implementing RAMS principle and
process as suggested by EN50126/128/129 or equivalent.

1.3 If there is lack of RAMS Assurance, the following may happen-

(a) Loss of KPI
(b) Customers satisfaction, project credibility will be on doubt

(c) Global Certification may not be possible
(d) Development as well as operational cost will be more.

2.0 Terms and Definitions

2.1 Please refer to Glossary of terms

2.2 Safety Assurance Acts & Standards:
a) Indian Railways Act

b) Metro Railway Act

c) International Standards (EN50126, 50128, 50129 or equivalent)
d) ROGS Legislation 2006 (Railway and other Guided Transport Systems)

Annexure:G1: Reliability, Availability, Maintainability & Safety (RAMS) Page 497 of 535