Unit 51 Emergency Shutdown and Safety Systems



Unit 51:

Emergency Shutdown and Safety

 

 

Systems


Unit code:
J/601/1420

QCF level:
4


Credit value:
15






Aim

This unit will provide learners with an understanding of safety shutdown systems as employed in modern industry.

Unit abstract

This unit will give learners an overview of the principles, technology, instrumentation and operational and maintenance requirements applied in safety shutdown systems. The unit can form the basis of further study at a more advanced level in this specialist area of instrumentation and control.

Learning outcome 1 will provide learners with knowledge and experience of the principles of safety shutdown. This includes safety shutdown philosophy and the aims and objectives of shutdown systems. Learning outcome 2 introduces the applied technology and techniques employed in safety shutdown systems. Learners will then evaluate the use of instrumentation in safety shutdown systems before investigating the operational and maintenance requirements.

Learning outcomes

On successful completion of this unit a learner will:

1       Understand the principles of safety shutdown systems

2     Understand the applied technology and techniques used in safety shutdown systems

3       Understand the use of instrumentation in safety system applications

4       Understand the operational and maintenance requirements for safety shutdown systems.


Unit content

1      Understand the principles of safety shutdown systems

Principles: aims and objectives of shutdown systems eg protection of personnel, plant, equipment, safe operation, protection of the environment; hierarchy of protection eg ultimate protection through containment, pressure relief devices, bursting discs; automatic shutdown; manual shutdown; control systems to regulate processes and provide localised plant trips; alarm systems to provide audible and visual warning

Safety shutdown: analysis of hazard potential; hazard and operability (HAZOP); hazard analysis (HAZAN); failure mode and effect analysis (FMEA); failure to least hazardous condition; simplicity of system; evaluation of a conceptual proposal for an overall safety shutdown system


2      Understand the applied technology and techniques used in safety shutdown systems

Applied technology: logic arrangements; electrical; electronic (including software based); mechanical; pneumatic; hydraulic; input/output devices

Shutdown techniques: emergency ‘back up’ and support systems; local and remote shutdown arrangements; levels of shutdown dependent upon severity of hazard detected; module shutdown; plant/process shutdown; total installation shutdown; bypass arrangements; dispensation and exclusions from shutdown

Design criteria: independence of operation from other instrumentation and control systems; protection against external influences eg electromagnetic interference (EMI); logical structuring of alarm and shutdown sequences; interface arrangements with other systems eg fire and gas detection/protection systems and process/manufacturing control systems; override and resetting arrangements; reliability and availability of system; protection against common mode failure (CMF); segregation; diversity; redundancy; voting systems


3      Understand the use of instrumentation in safety system applications

Selection of instrumentation: manufactured to appropriate standards eg BS, CEN, ISO/IEC, ISA, ANSI; suitability for intended purpose and location

Safety applications for instrumentation: installation and maintenance requirements; input devices for detection of plant; process and manufacturing abnormalities; fire, gas, chemical, vapour, collision eg input sensors for level, pressure, temperature, speed, position; manual and automatic initiation; output shutdown devices eg actuators, valves, indicators, electrical/electronic trip switches

Hazardous area instrumentation: intelligent instrumentation for both input and output functions; hazardous area classification; zonal concept; principle of intrinsic safety and explosion proof equipment; standards eg BS, BASEEFA, CENELEC



4      Understand the operational and maintenance requirements for safety shutdown systems

Safety system operation: operation manual and operational procedures; personnel responsibilities; bypass arrangements; override operations; interlocks; monitoring of operational status of plant; equipment; manufacturing process; remote shutdown operations

Maintenance requirements: the need to meet statutory requirements; appropriate maintenance documentation and record keeping; inspection routines; online monitoring; manual and automatic testing; condition monitoring; event recording





Learning outcomes and assessment criteria


Learning outcomes
Assessment criteria for pass


On successful completion of
The learner can:


this unit a learner will:










LO1 Understand the principles of

1.1
explain the principles of safety shutdown systems


safety shutdown systems

1.2
evaluate a conceptual proposal for an overall process









safety shutdown system








LO2 Understand the applied

2.1
identify the applied technology and techniques used in


technology and techniques


safety shutdown systems


used in safety shutdown

2.2
explain the design criteria that are applied to safety


systems





shutdown systems












LO3 Understand the use of

3.1
select suitable instrumentation for use in a safety


instrumentation in safety


shutdown application


system applications

3.2
identify specific requirements for safety instrumentation









in a hazardous area environment




3.3
evaluate the use of instrumentation in a safety system





application







LO4 Understand the operational

4.1
determine the operational requirements for a safety


and maintenance


shutdown system


requirements for safety

4.2
determine the maintenance requirements for a safety


shutdown systems





shutdown system.














Guidance
Links

The unit has links with Unit 6: Health and Safety and Risk Assessment in Engineering, Unit 24: Application of Pneumatics and Hydraulics and Unit 50: Condition Monitoring and Fault Diagnosis.

Essential requirements

Centres delivering this unit must be equipped with simulated shutdown equipment to industrial standard or have access to industrial organisations offering such facilities.

Employer engagement and vocational contexts

Liaison with employers would be a benefit to centres, especially if they are able to offer access to suitable industrial plant and equipment.

Comments