Determine Risk-based Maintenance Strategies
William M. Bradshaw, ABSG Consulting Inc., 10301 Technology Drive,
Knoxville, TN, 37932 (865) 671-5829, WMBradshaw@ABSConsulting.com
Jonathan Babcock, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, 46285
(317) 277-1169, Babcock_Jonathan_B@Lilly.com
Robert E. Behnke, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, 46285
(317) 277-2686, Behnke_Robert_E@Lilly.com
Kerry Beidelman, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN, 46285
(317) 433-1159, Beidelman_Kerry@Lilly.com
Keywords: Process hazard review, mechanical integrity, pharmaceutical processes
Abstract
Over the years, many companies have struggled to determine the appropriate mechanical integrity (MI) test, inspection, and condition monitoring activities for process equipment that help prevent or mitigate potential accident scenarios involving highly hazardous chemicals. One widely used approach relies on recognized and generally accepted good engineering practices (RAGAGEPs) and manufacturers’ recommendations, often adjusted based on historical plant practices and failures observed at the facility or within the company. While this approach works well for common items such as pressure vessels and pressure relief devices, it is often difficult to apply to process-specific items such as alarms and interlocks that are not part of a safety instrumented system. In fact, many safeguards that are identified in process hazard reviews (PHRs) are not well addressed by RAGAGEPs or manufacturers’ recommendations.
To help ensure that maintenance strategies are better aligned with risk, PHR teams at one Lilly facility have recently started specifying maintenance strategies for all safeguards identified in hazard and operability studies. PHR teams specify the required maintenance strategy for each safeguard using a five-category ranking system (e.g., a full function test, periodic calibration or other maintenance). This determination is based on (1) the potential consequence severity and frequency of the postulated accident scenario, (2) the team’s qualitative assessment of the safeguards identified for the scenario, and (3) the team’s assessment of what MI activities are needed to achieve acceptable risk.
This paper describes how (1) these maintenance strategies are determined in an efficient manner and (2) Lilly uses the results to “right size” its approach to maintaining process equipment that serves a safety function.
See more of this Group/Topical: Global Congress on Process Safety