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INNOVATIVE TECHNOLOGY

Facilities". As a result of hazard and risk
SIL-oriented hike. How to apply GOST R analysis in accordance with the requirements
IEC 61511 of clause 8.2.1 of GOST R IEC 61511-1-2011
By definition, the Safety Instrumented [3], the following should be:
Function (SIF) includes all elements from the 1) descriptions of each specific dangerous event
sensor to the actuator (Fig. 3). The probability and factors influencing it are received;
of a circuit failure when requesting a lock is 2) a description of the consequences and
equal to the sum failure probabilities of elements credibility of the event;
included in the circuit. 3) conditions are considered, such as
Simplified: PFDloop = PFDsensor + PFDplc conditions of normal operation, start-up,
+ PFDvalve. shutdown, maintenance, start-up of the
Therefore, if the SIL3 controller is present in process, emergency shutdown;
the considered circuit, but the outdated and 4) requirements are established for
inadequate "field" equipment does not meet the additional risk reduction necessary to
safety integrity requirements, then the safety achieve the required safety;
integrity level of the entire circuit will be SIL0. 5) a description has been made (or
The task of moving from "controller appropriate links given) of measures taken
requirements" to "circuit requirements" is to to reduce or eliminate dangers and risks;
perform the following activities: 6) the assumptions made during the risk
● compliance with the EAP system project analysis are described in detail, including
implementation stages according to GOST R the probable intensity of the requests and
IEC 61511: from hazard and operability analysis the failure rate of the equipment, as well
(HAZOP) to the distribution and assignment of as any information about the limitations of
SIL levels to safety functions, development of working conditions and human intervention;
EAP system requirements (SRS specifications); 7) the distribution of security functions
● organizational measures at the enterprise among protection layers is accepted,
(functional safety management, personnel taking into account a possible decrease in
training, organization of verification processes, protection efficiency caused by a failure
procedures and accounting); due to a common reason, it is possible
● technical measures at the enterprise (functional both between different protection layers
safety assessment tools); and between these layers and the common
● willingness of suppliers to perform work. process control system (DCS);
As a result, it is advisable for the customer 8) those safety functions are defined that
of the EAP system to divide the work into two are implemented as safety functions of a
stages: safety instrumented system (EAP).
1) performing a hazard and risk analysis; ● Establishment of SIL safety integrity levels
2) delivery and performance of work on the EAP (assigned by SIL) for the safety function
system. implemented on the EAP system.
● Development of a conceptual specification
of safety requirements (Safety Requirment
Specification), according to GOST R IEC
61511-1, based on the results of the stage
hazard and risk analysis. As a rule, the first
stage should be performed by an expert
organization independent of the supplier,
since the results of the stage (list of SIF
protection circuits and assigned SIL) directly
affect the solution specification and its cost.

Technical assignment Hazard and risk analysis can be carried out
by a design institute for a new construction
site or by an organization-independent
organization with the necessary expertise
The following tasks should be included in when modernizing an automated process
the terms of reference for the first stage. control system. The conceptual specification
● Identification, analysis and forecasting of of safety requirements (SRS) should contain
the risk of accidents [2] in accordance with general requirements for the safety system,
paragraph 4 of Article 11 of Federal Law No. 116 a list of protection loops and requirements
"On Industrial Safety of Hazardous Production for each of them, architectural solutions

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