ANSI/ISA 84.00.01-2004 (IEC 61511 modified)
requires that the operation, maintenance,
and testing procedures for the Safety Instrumented System (SIS) contain the following:
- Set points and actions.
- Hazard that you are trying to prevent.
- When to use bypasses.
- Response to diagnostic alarms
– Compensating measures.
- When to execute a safe shutdown.
SIS-TECH generates a
step by step procedure covering the essential activities and any
information that should be collected during the activity, Since we also
understand the potential failure modes of SIS devices, the procedures
take these modes into account ensuring that functional tests accurately
identify hidden faults and minimizing the chances of a spurious trip
during testing. Once the procedures are complete, we provide training
and training packages. Our extensive field experience makes our
training programs more interesting and focused, resulting in better
trained operation and maintenance staff.

Call SIS-TECH for assistance
with any of the following:
Effective proof test procedures demonstrate the functionality of the SIS devices.
SIS-TECH generates step-by-step procedures incorporating
sign-off spaces for critical steps. These procedures
have sufficient detail to address testing of the critical
device functionality and to provide verification that
the technician has returned the device to service
after testing. In addition, the procedure establishes
the appropriate communications between the operator
and the proof test technician. SIS-TECH procedures
contain the following information:
- Safety function description
- Safety function drawings
- Trip values
- Instrument ranges
- Testing tolerances
- Communications to occur between technician
and control room
- Bypass initiation, if required
- Alarms
- Indications
- Back in service notification
- Test approval
Proof testing is performed to
expose dangerous failures that would otherwise
remain undetected until a demand occurred, potentially
resulting in a process hazard. If off-line testing
is performed, a well-planned and executed test program
can reduce the time required for testing, minimizing
the potential for a start-up delay. As plant reliability
programs enable plants to reach longer turnaround
intervals, off-line testing opportunities are becoming
fewer. In many cases, testing the SIS devices at turnaround
is insufficient to meet the integrity requirements.
On-line testing presents the potential for spurious
trips during the test. SIS-TECH can minimize this
risk by providing personnel experienced in procedure
development, manpower planning, site supervision,
training, and auditing.
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SIS-TECH can provide operator
training for a specified Safety Instrumented
System (SIS). This training is typically specific
to the following:
- Unit Startup/Normal Shutdown
- Safety System Permissives
- Automatic Shutdown/Recovery
- System Bypassing
- Response to Critical Alarms
Development of training material requires a multi-disciplinary
team that has experience with the process unit. The
team typically consists of representatives from operations,
process, and maintenance departments. Effective training
materials enhance operator understanding of the SIS
and its potential effect on the process unit. The
training course material contains step-by-step procedures
with sufficient detail to cover the safe operation
of the SIS during startup, operation, and shutdown
of the process unit.
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Detailed procedures
are used to cut-over the process unit from the existing SIS to the new
SIS, while the process in on-line and operating. These procedures are
intended to minimize unplanned outages of the operating process unit.
SIS-TECH generates step-by-step procedures guiding
the cut-over team through critical steps of the SIS
cut-over. The procedures have sufficient detail to
allow verification of the following:
- SIS devices are inspected and tested,
- SIS is fully functional, and
- The process unit is under the control
of the SIS.
The procedure outlines the communication required
between the cut-over team and the control room operator.
SIS-TECH procedures include the following information:
- Safety Functional Description
- Operator Assistance Requirements
- Bypasses
- Alarms
- Testing
- Return process to normal service
- Cut-over Team
- Cut-over package (procedure and drawings)
- Inspection
- Testing
- Return process to normal service
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