Process Safety Engineering

Process Safety is a disciplinary framework for managing the integrity of operating systems and handling hazardous substances that involves the facilities to be well designed, safely operated, and properly maintained the facilities and hazardous materials. The Process Safety focuses on the prevention and control of incidents that have the potential to release hazardous materials or energy that can cause toxic effects, fire, or explosion and could ultimately result in serious injuries, property damage, lost production, and environmental impact.

Process Safety Engineering is a safety specialised process engineering discipline that is responsible for the developing risk assessments and designing safety operating practices, and provides technical leadership and support to identify hazards, assess risks and provide cost-efficient management solutions. The Process Safety Engineering focuses on the prevention of fire and explosion, accidental chemical release, and reactive chemistry, toxic exposure, overpressure/under pressure, equipment malfunction, excessive temperature and thermal expansion, metal fatigue, corrosion, human factors, and other similar conditions by the application of good engineering and design principles.

Process Safety Information (PSI) is the physical, chemical, and toxicological information related to the chemicals, processes, and equipment. A PSI is concerning the hazards of the regulated materials which is typically found in a material: safety data sheet (MSDS); Block flow diagram or simplified process flow diagram; Process chemistry; Maximum intended inventory; Safe upper and lower limits for such items as temperatures, pressures, flows or compositions; and an Evaluation of the consequences of deviations.

Process Safety Management (PSM) is a safety management system concerned with the safety hazards arising from process operations, and distinct from the management of conventional safety (slips, trips, falls etc.). A PSM requires detailed knowledge of the chemical and process hazards associated with the operations of the plant that is a regulation by the U.S. Occupational Safety and Health Administration (OSHA).

Fire Fighting is an activity or a process of extinguishing fires burning.

Alarm Management is the process of effectively handling and responding to alarms that controls and manages the design of alarm systems with human factors, instrumentation engineering and systems. The Alarm Management System includes procedures, documentations, characterisations, logics, prioritisations, schematics, software and hardware, and maintenance, etc. in various systems, such as industrial control systems, computer networks, and security systems for the classifying alerts, prioritising, grouping and event notifications. (Refer to the Alarm Flooding)

Emergency Shutdown (ESD) system is a process safety control system which overrides the action of the basic control system when predetermined conditions are violated that includes an emergency shutdown valve (ESD Valve) and an associated valve actuator. The Emergency Shutdown Controller provides output signals to the ESD valve in the event of a failure in the process control system.

Emergency Sequence is the detailed procedures on how to make plant and process safe, minimising risks to operators and facilities at all stages covering the PPE, level of intervention which is safe and when to evacuate. The Emergency Sequence in the process operation is an automatic sequence initiated by an interlock that may consist of starting, stopping, opening, or closing equipment in order to render the process safe.

Emergency Shutdown Device is a device that is designed the system shutdown safely from the emergency conditions.

Emergency Relief Device is a device that is designed to prevent rise of internal fluid pressure in excess of a specified value and mounted on tanks with fixed roof for volatile liquids. (Refer to the Process Safety Valve (PSV) or Pressure Relief Valve (PRV))

Emergency Shutdown Valve (ESDV) is an actuated valve designed to close the flow of a hazardous fluid when the detection of a dangerous event happens. ESDVs are the final defence against process mal-operation; they have a function which requires much more reliable performance than standard on-off valves. Whenever dedicated sensors identify an abnormally dangerous process situation, the power to an ESD valve solenoid and the valve goes to the desired fail safe mode (fail close or fail open) as a part of a Safety Instrumented System (SIS).

Remotely Operated Shut-Off Valve (ROSOV) is a type of Emergency Shutdown Valve (ESDV) which allows a plant or facility to be isolated automatically from a safe location without the necessity for manual intervention that is designed and installed for the purpose of quickly isolating plant items which are used for the storage of hazardous substances. In the Remote Operated Shut-Off Valve (ROSOV) scenario, in an emergency shutdown the actuator will immediately return to the predetermined safe position and will be ready to operate on the next command when the ESD signal is reinstated.

Emergency Systems Survivability Analysis (ESSA)

Boiling Liquid Expanding Vapor Explosion (BLEVE) is a vapour explosion caused by the rupture or catastrophic failure of a vessel containing a pressurised liquid, which is handling and storing pressure vessel or containing cargo liquid above the boiling point at nominal atmospheric pressure.

Fail to Danger is a failure mode of the protection system that becomes shutdown if there is a failure in any of its components. The Fail to Danger fault of a hazardous condition arising the equipment, process, or plant will continue to operate without being tripped but it has a direct and detrimental effect on safety.

Fire Triangle is the three elements needed to ignite or for fire that is: 1) flammable substance (combustible material): to burn; 2) oxygen: to combine and react; 3) heat or ignition source: to raise the temperature of the combustible material to its burning or ignition temperature.

Flash Fire is defined from NFPA standard as a fire that spreads by means of a flame front rapidly through a diffuse fuel, such as dust, gas, or the vapours of an ignitable liquid, without the production of damaging pressure. Flash fires generate temperatures in the range from 1000ºF to 1900ºF.

NFPA (National Fire Protection Association) 55 is a standard for the storages, uses, and handling of compressed gases and cryogenic fluids in portable and stationary containers, cylinders, and tanks that covers facilitates protection from physiological, over-pressurisation, explosive, and flammability hazards associated with compressed gases and cryogenic fluids.

Sprinkler is a device or equipment that sprays water for putting onto fires in a lot of small drops to put them out.

Vapour Cloud Explosion (VCE) is an explosion resulting from the ignition of cloud of flammable vapor, gas, or mist in which a flame speed accelerates to sufficiently high velocities to produce significant overpressure. These explosions occur by a sequence of steps: 1) Sudden release of a large quantity of flammable vapor; 2) Dispersion of the vapor throughout the plant site while mixing with air; 3) Ignition of the resulting vapor cloud.

• Extinguishing Systems Design of fixed fire extinguishing system (e.g., foam, carbon dioxide, clean agent, and/or dry powder systems) *
• Fire & Gas Cause & Effects Matrix
• Fire and Gas Detection Equipment Schedule
• Fire Fighting Equipment Layout
• Fire Fighting Equipment List/ Requisition
• HAZOP Report
• Mobile Fire Fighting Equipment Schedule
• P&ID for Fire Water Ring Main
• Safety Design Philosophy
• Safety Equipment Schedule
• Safety Signs Drawing

Centre for Chemical Process Safety (CCPS) is a not-for-profit, corporate membership organization within AIChE that identifies and addresses process safety needs within the chemical, pharmaceutical, and petroleum industries. CCPS brings together manufacturers, government agencies, consultants, academia and insurers to lead the way in improving industrial process safety. In order to protect people, property and the environment, CCPS is committed to bringing the best process safety knowledge and practices to industry, academia, the government and the public around the world through collective wisdom, tools, training and expertise. (Source: www.aiche.org/ccps/)

National Fire Protection Association (NFPA) is founded in 1896, NFPA is a global, non-profit organization devoted to eliminating death, injury, property and economic loss due to fire, electrical and related hazards. The association delivers information and knowledge through more than 300 consensus codes and standards, research, training, education, outreach and advocacy; and by partnering with others who share an interest in furthering the NFPA mission. (http://www.nfpa.org/)