Safety Engineering

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Safety engineering, abbreviated as SAF, also known as safety management or safety science, is a discipline that focuses on ensuring the safety of people, equipment, processes, and environments.  It involves the application of scientific and engineering principles to identify, assess, and control potential hazards and risks in various settings.  The primary goal of safety engineering is to prevent accidents, injuries, and adverse events by designing and implementing effective safety measures and controls.  It encompasses a wide range of industries and sectors, including manufacturing, construction, transportation, healthcare, energy, and more.

Safety Index

Overall, safety engineering is a multidisciplinary field that combines engineering, science, psychology, and management principles to create safe and secure environments for individuals and society as a whole


Science Branches

Applied Science
Management and Systems Engineering

Work Place Hazards

  • Biological
    • Animal and bird droppings
    • Bacteria and viruses
    • Blood and other body fluids
    • Fungi/mold
    • Insect bites
    • Plants
  • Chemicals
    • Carcinogens
    • Corrosives
    • Gasses
    • Flammable materials
    • Irritants
    • Liquids
    • Mutagens
    • Pesticides
    • Sensitizers
    • Teratogens
    • Vapors
  • Ergonomic
    • Frequent lifting
    • Poor posture
    • Vibration
  • Physical
    • Awkward movements
    • Burns
    • Constant loud noise
    • Crush injuries
    • Falls
    • Having to use too much force
    • High exposure to sunlight/ultraviolet light
    • Improperlt adjusted workstation and chair
    • Radiation
    • Temperature extremes
  • Psychosocial
    • Harassment
  • Safety hazard
    • Confined spaces
    • Electrical
    • Fire
    • Forklifts
    • Lockout/tagout
    • Machinery
    • Lack of PPE
    • Lack of training
    • Poor housekeeping
    • Spills
    • Tools
    • Working at height


Confined Space Entry

  • Confined space
    • The space is large enough for you to enter and conduct work.
    • The space is not intended for continuous human occupancy.
    • Limited openings for entry and exit.
    • Examples: bins, boilers, ducts, furnaces, hoppers, manholes, pipes, pits, sewers, silos, tanks, trenches, tunnels, vaults
  • Potential hazards in confined spaces
    • Combustibles
    • Electricity
    • Mechanical hazards
    • Oxygen deficiency
    • Toxic materials
  • Immediately dangers to life or health
    • Any condition which poses an immediate threat to the health of life on an entrant
    • Would cause irreversible adverse health effort
    • Would interfere with an individual's ability to escape unaided from a permit space
  • Permit required confined space entry procedure
    • Isolate the space
    • Ventilate the space
    • Conduct tailboard
    • Complete permit
    • Test the atmosphere
    • Enter the space
  • Isolate the space from all hazards
    • Close valves
    • Enter the space
    • Lockout/Tagout equipment
    • Clean residue from the space
  • Ventilate the space
    • Use mechanical ventilation
    • Ventilate at the rate of at least four volumes per hour
    • Make sure air supply is not contaminated
  • Conduct a tailboard briefing
    • Entire crew must attend
    • Review hazards of entry and work
    • Review PPE
    • Review procedure for contacting rescue
    • Complete permit
  • Complete entry permit form
    • Permit must be correctly and completely filled out prior to entry
    • Permit must be activated by entry sipervisor's signature to be valid
    • No entry is allowed without  a valid permit
    • Permits are valid for up to 12 hours
    • When work is completed, permit and tailboard form should be returned to safety
    • Canceled permits must be kept on file for at least one year


Safety Engineering Standards

ISO Standards

  • ISO 1709 - Nuclear energy -- Fissile materials -- Principles of criticality safety in storing, handling and processing
  • ISO 1819 - Continuous mechanical handling equipment -- Safety code -- General rules
  • ISO 3165 - Sampling of chemical products for industrial use -- Safety in sampling
  • ISO 3265 - Continuous mechanical handling equipment for loose bulk materials -- Wagon tipplers handling rail-borne wagons (rotary, side discharge and end discharge) -- Safety code
  • ISO 3691 - Powered industrial trucks -- Safety code
  • ISO 5031 - Continuous mechanical handling equipment for loose bulk materials -- Couplings and hose components used in pneumatic handling -- Safety code
  • ISO 4126-1 - Safety devices for protection against excessive pressure -- Part 1: Safety valves
  • ISO 4126-2 - Safety devices for protection against excessive pressure -- Part 2: Bursting disc safety devices
  • ISO 4126-3 - Safety devices for protection against excessive pressure -- Part 3: Safety valves and bursting disc safety devices in combination
  • ISO 4126-4 - Safety devices for protection against excessive pressure -- Part 4: Pilot operated safety valves
  • ISO 5175 - Equipment used in gas welding, cutting and allied processes -- Safety devices for fuel gases and oxygen or compressed air -- General specifications, requirements and tests
  • ISO 5388 - Stationary air compressors -- Safety rules and code of practice
  • ISO 10417 - Petroleum and natural gas industries -- Subsurface safety valve systems -- Design, installation, operation and redress
  • ISO 16069 - Graphical symbols -- Safety signs -- Safety way guidance systems (SWGS)
  • ISO 16708 - Petroleum and natural gas industries -- Pipeline transportation systems -- Reliability-based limit state methods
  • ISO 17398 - Safety colours and safety signs -- Classification, performance and durability of safety signs
  • ISO 17846 - Welding and allied processes -- Health and safety -- Wordless precautionary labels for equipment and consumables used in arc welding and cutting
  • ISO 21789 - Gas turbine applications -- Safety


Tags: Abbreviations Nomenclature and Symbols

Safety Engineering GlossaRy


  • Action Owner  -  The individual assigned responsibility for completion of a corrective action.
  • Active Controls  -  Controls that require some action to prevent or mitigate a hazard.
  • Administrative Controls  -  Controls which require action on the part of an individual to be effective.
  • After Action Review  -  A structured review or de-brief process for analyzing what happened, why it happened, and how it can be done better by the applications and those responsible for the project or event.
  • Alternate Entry Procedures  -  Alternate entry procedures may be used when the only hazard is an actual or potential hazardous atmosphere.
  • Area Classification Drawing  -  Outlines the classifications of areas where flammable liquids, gasses or vapors are handed, processed or stored.  It is created based on input from the Process Flow Diagrams, Piping & Instrumentation Diagrams and the Equipment Location Plan.
  • Asbestos Abatement  -  Procedures used to control fiber release from asbestos containing materials during removal activities.
  • Atmosphere  -  The gasses around an object in space (planets and stars).  The earths atmosphere is not its original atmosphere.
  • Audit  -  The examination of the financial records of a buisness, person, or organization.
  • Authorized Attendant  -  A trained individual stationed outside the permit space to monitor the authorized entrants and to perform all attendance duties.
  • Authirized Employee  -  A person who locks out or tags out machines or equipment to perform services or maintenance.
  • Authorized Entrant  -  An employee who is authorized by the employer to enter a permit-required confined space.


  • Bio-hazaedous Waste  -  Waste or materials that contain biological materials such as human or animal blood, tissue, or bodies or body parts or sewer water.
  • Building Codes  -  Model building codes are adopted by each municipality from the major code organizations.
  • Business Partner Safety Responsibilities  -  Business partner operations will be performed in accordance with the company/federal safety practices.


  • Competency  -  Having the necessary knowledge or technical skills to perform a given task.
  • Compressed Gas  -  Any material which is a gas at normal temperature and pressure, and which is contained under pressure as a dissolved gas or liquefied by compression or refrigeration.
  • Confined Space  -  A space that is large enough and so configured that an employee can bodily enter and perform assigned work.
  • Confined Space Ventilation  -  An employee may not enter the space until the forced air ventilation has eliminated any hazardous atmosphere.
  • Corrective Action  -  An activity that restores a service, item, component, or process to a state of acceptable compliance with specifications, procedures, or regulatory requirements.
  • Corrosion  -  The thinning of a pipe wall that is typically caused by a chemical reaction from a corroding fluid or agent and is limited almost exclusively to metal products.
  • Corrosive  -  A chemical that causes visible destruction of or irreversible alterations in living tissue by chemical action at the site of contact.
  • Cost-effective  -  Providing adequate financial return in relation to outlay.
  • Cost-efficient  -  Being efficient without wasting effort, expense, or time.


  • Days Away, Restricted, or Transferred  -  Designed to track any recordable workplace injuries or illnesses that result in time away from work, restricted job roles, or an employee's permanent transfer to a new position.


  • Electrical Hazard  -  A dangerous condition such that contact or equipment failure can result in electric shock, arc flash burn, thermal burn, or blast.
  • Electrical Safety  -  Recognizing hazards associated with the use of electrical energy and taking oresautions so that hazards do not cause injyry or death.
  • Emergency Manager  -  Responsible for ensuring that staff maintains an approperate level of readiness.
  • Emergency Management  -  The process an organization uses to prevent, mitigate, and recover from emergencies.
  • Emergency Planning  -  Developing and preparing emergency plans and procedures.
  • Emergency Preparedness  -  The training of personel, acquiring and maintaining resources, exercising plans and procedures for emergency response.
  • Employee Safety Responsibilities  -  Each employee shall work in a safe manner while watching out for their fellow employees and business partners.
  • Energy Isolation Device  -  A mechanical device that physically prevents the transmission or release of energy
  • Entry Permit  -  The written or printed document that is provided by the employer to allow and control entry into a permit required confined space.
  • Entry Supervisor  -  The trained individual with the responsibility to ensure that acceptable entry conditions are present within a permit space under his or her jurisdiction.
  • Ergonomics  -  The concept of identifying and correcting factors in the workplace focusing on maximizing productivity by minimizing operaror fatigue and discomfort.
  • Explosive  -  A compound, mixture, or substance that is capable of producing an explosion.
  • Extension Cords  -  Extension cords are designed and should only be for temporary use.


  • Factor of Safety  -  The ability of a system's structural capacity to be usable beyond it's expected or acrual loads.
  • Fail Closed  -  Fail Closed means the valve will closed when the signal is interrupted. An example of this would be block valves closing to isolate a steam injection well on loss of power. Because uncontrolled steam is dangerous and potentially lethal, automatic valve closure might be required.
  • Fail Open  -  Fail Open is the term whee a valve opens at loss of signal. This scenario might be chosen to prevent overpressure in the event of a blocked line or in case of a catastrophic failure.
  • Fail in Place  -  Fail in Place might apply to a ball valve or a control valve that does not react on loss of power or signal. This would be used where the process cannot be shut down or where it is undesired to do so.
  • Fail Position  -  Fail position is the term used to describe how an actuator reacts when there is a loss of power, loss of signal or similar event. There are three different fail scenarios, each has its own consequences and safety effects.
  • Fire Area  -  The aggregate floor area enclosed and bounded by building seperation walls, fire barrier walls, exterior walls or fire-resistance rated horizontal assemblies of a building.
  • Fire Barrier Wall  -  A fire-resistance rated wall, having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the floor.
  • Fire Code  -  A set of legally adopted rules and regulations designed to prevent fires and protect lives and property.
  • Fire Detection System  -  An engineered system of devices that automatically detects heat, smoke, or other products of combustion and activates an alarm.
  • Fire Partition  -  A vertical assembly of materials having protected openings and designed to resist the spread of fire.
  • Fire Protection Equipment  -  Any type of equipment used in the extinguishing or suppression of a fire.
  • Fire Resistance Rating  -  A minimum rating established by the National Fire Protection Association is which materials must meet to prevent and retard combustion.
  • Fire Seperation Wall  -  A fire-resistance rated wall, having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the floor.
  • Fire Suppression Equipment  -  All equipment used to extinguish a fire.
  • Flame Resistant  -  The property of a material whereby combustion is prevented, terminated, or inhibited following application of a flaming or non-flaming source of ignition, with or without subsequent removal of the ignition source.
  • Flammable  -  Capable of being readily ignited.
  • Flammable Liquid  -  A liquid which can readily catch fire.
  • Flammable Solid  -  Solids that are liable to cause fire through friction or absorption of moisture.
  • Flashover  -  The stage of fire when all surfaces and objects are heated to their ignition temperature and flame breaks out almost at once over the entire surface. 
  • Flash Hazard  -  A dangerous condition associated with the release of energy caused by an electric arc.
  • Flash Hazard Analysis  -  A study investigating a worker's potential exposure to arc-flash energy, conducted for the purpose of injury prevention and the determination of safe work practices and the approperate levels of PPE.
  • Flash Point  -  The lowest temperature of a flammable liquid at which it gives off sufficient vapor to form an ignitable mixture with the air near the surface of the liquid or within the container used.
  • Flash Protection Boundary  -  An approach limit at a distance from exposed live parts within which a person could receive a second degree burn if an electeical arc flash were it occur.
  • Flange Safety Spray Shield  -  Used on equipment (flanges in this case) where fluids are under pressure and need to be prevented from leaking or spraying on other equipment or people.


  • Generic Hazard  -  A hazard which may be generally present throughout an operation or industry, but which may have widely different levels of risk, depending on the specific site characteristics.
  • Greenhouse Gases  -  Gases that alter the thermal properties of the atmosphere.


  • Hazard  -  Any source of potential damage, harm or adverse health effect to someone or something.
  • Hazard Level  -  The level assigned to the identified hazard prior to applying the hazard reduction sequence corrective action.
  • Hazardous Atmosphere  -  An atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue.
  • Hazardous Energy Control  -
  • Hazardous Material  -  Any solid, liquid, or gaseous material that is not radioactive but is toxic, explosive, flammable, corrosive, or otherwise physically or biologically threatening to health.
  • Hazardous Substance  -  A substance, gaseous, liquids, or solids, that can harm people's health.
  • Health Hazard  -  Can result in the developement of disease.
  • High Contamination Area  -  An area, accessible to individuals, where removeable surface contamination levels exceed or are likely to exceed 100 times the removeable surface contamination values.


  • Ignition Point  -  The minimum temperature at which a substance will burn.
  • Incendiary Fire  -  An intentionally srt fire.
  • Incident  -  An undesired workplace event that causes personal injury or illness, property or equipment damage, environmental damage, or disruption of operations.
  • Injury Frequency Rate  -  The number of injuries based on the number of hours worked on an annual basis.
  • Injury Severity Rate  -  How critical or serious the injuries and illnesses sustained in a period of time by using the number of lost days per accident.
  • Intermittent Noise  -  Broadband sound pressure level exposure several times throughout the day.
  • Irritant  -  A non-corrosive substance which can cause inflammation on the body through contact.


  • Job-related Injury/Illness  -  An injury or illness that occurs by accident and arises in the course of employment.



  • Ladders  -  Before using a ladder, visually inspect it.  Defective ladders shall not be used and shall be removed from service and tagged or disgarded.
  • Lockout  -  The placement of a lockout device on an energy isolating device in accordance with an established procedure, ensuring that the energy isolating device and the equipment being controlled cannot be operated until the lockout device is removed.
  • Lockout Device  -  A device that utilizes a positive means such as a lock, either key or combination type, to hold an energy isolating device in the safe position and prevent the energizing of a machine or equipment. Included are blank flanges and bolted slip blinds.
  • Lockout/Tagout Positions  -
  • Lockout/tagout Procedures  -  Can vary significantly from project to project.  For this reason everyone working on a project should know the policies for equipment lockout/tagout to create a safe work place.
  • Lock Closed  -  Is used on valves that must be closed during normal operating conditions. A valve is termed "Lock Closed" when it is required by the applicable code, safety protocols or standard operating conditions.
  • Lock Open  -  Is used on valves that must be open during normal operating conditions. A valve is termed "Lock Open" when it is required by the applicable code, safety protocols or standard operating conditions.
  • Lost Time Injury Frequency Rate  -  The number of lost time injuries that have occured within a given accounting period, relative to the total number of hours worked in that period.
  • Lost Time Injury Incident Rate  -  The number of incidents that result in time away from work.
  • Lost Workday Incident Rate  -  The total number of working days lost within a workplace due to occupational injury or illness.
  • Lower Explosive Limit  -  The minimum concentration of vapor or gas in air below which propagation of flame does not occur on contact with a source of ignition.
  • Lower Flammable Limit  -  The minimum concentration of vapor or gas in air below which propagation of flame does not occur on contact with a source of ignition.


  • Margin of Safety  -  The ratio of the system's structural capacity to the requirements or how much excess capacity.
  • Margin of Safety for a Failure load  -  The ratio of the system's structural capacity to the requirements or how much excess capacity.
  • Member of the Public  -  An individual who is not a general employee.
  • Modification  -  Any change made to structures, systems, components, or procedures during any phase of the life of the facilities.


  • Natural Ventilation  -  The pulling of fresh air into a building from the outside.
  • Near Accident  -  Any event which had the potential to cause injury and/or damage and/or loss, but which was avoided by circumstances.
  • Near Miss  -  Any event which had the potential to cause injury and/or damage and/or loss, but which was avoided by circumstances.
  • Noise Induced Hearing Loss  -  An incurable condition caused by both acute and chronic exposure to a loud noise.
  • Non-permit Confined Space  -  The space does not contain hazaeds that could cause death or serious harm.
  • Normal Operation  -  The utilization of a machine or equipment to perform its intended production function.
  • Normally Closed  -  Normally closed, as its name implied, it is to show which valve are open during standard operating conditions.
  • Normally Open  -  A normally open, as its name implied, it is to show which valves are open during standard operating conditions.


  • Occupied Area  -  Any work area to which personnel are assigned or any non-work area where persons reguladly congregate.
  • Occupational Hazard  -  A thing or situation with the potential to harm a worker.
  • Occupational Health Hazard  -  A source with the potential for harm in terms of injury or ill health.
  • Occupational Illness  -  An illness that occures in employees who have have been exposed to hazards when at work.


  • Permissable Exposure Limits  -  The regulatory limits on the amount or concentration of a substance in the air.
  • Personal protective Equipment  -  All equipment and clothing which is intended to be worn or held by a person at work and which affords protection against one or more risks to health and safety.
  • Pressure Safety Valve  -  Used to protect vessels and tanks from overpressure.  It is designed to protect critical system components such as pressure vessels, tanks and flange ratings.
  • Preventive Action  -  An activity that restores a service, item, component, or process to a state of acceptable compliance with specifications, procedures, or regulatory requirements.
  • Products of Combustion  -  Heat, smoke and toxic gasses.
  • Protected Area  -  A controlled access area encompassed by physical barriers.



  • Rescue Service Personnel  -  The company must identify emergency responders who are capable of responding to an emergency in a timely manner.
  • Residual Risk  -  Risk that remains after risk control measures have been implemented.
  • Response Owner  -  The person responsible for ensuring that all issues are completed and closed before the related event is submitted for closure.
  • Response Time  -  The time a fire company takes to get to a fire and begin fire operations.
  • Respiratory Protection  -  An apparatus worn by an individual for the purpose of reducing the inhalation of airborne materials.
  • Retention of Records  -  Canceled permits and other documentation will be retained by the company not less than one year following the date of entry.
  • Risk  -  A future event or problem that exists outside of the control of the project that will have an adveres impact on the project if it occures.
  • Risk Acceptance  -  Acknowledging a risk and not taking preemptive action against it.
  • Risk Analysis  -  The examination of risk areas or events to access the propbale consequences for each event, or combination of ecents.
  • Risk Avoidance  -  A risk response strategy whereby the project team acts to eliminate the threat or protect the project from its impact.
  • Risk Control  -  A strategy that involves deliberate action taken to reduce potential for loss, maintain risk at acceptable levels, or enhance potential for benefits, in a manner consistant with objectives, and desired outcomes.
  • Risk Gap  -  The difference between estimated risk and the tolerable risk.
  • Risk Identification  -  The process of identifying and examining risks and their affects on project objectives.
  • Risk Management  -  A process to access potential problems, determine which risks are important to deal with, and impliment strategies to reduce consequences.
  • Risk Mitigation  -  A risk response strategy whereby the project team acts to decrease the probability of occurance or impact of a threat.
  • Risk Plan  - The process of deciding how to approach and conduct the risk management activities of a project.
  • Risk Ranking  -  A process for ranking the severity and likelyhood of a hazard sequence of events to ensure the estimated risk of the sequence of events.
  • Risk Tolerance  -  The readiness or willingness of an organization or stakeholder to bear risk, considering potential tradeoffs and objectives.
  • Root Cause Analysis  -  A formal structured process for defining the root cause of an issue, event, or adverse ternd.
  • Routine Risk  -  Activities for which hazards have been previousely identified and mitigation measures are addressed in the safety manual.


  • Safety  -  The state produced by the control of recognized hazards to attain an acceptable level of risk.
  • Safety Hazard  -  Can cause accidents that physically injure workers.
  • Self-heating  -  An exothermic reaction within a material resulting in a rise in temperature in the material.
  • Self-ignition  - Ignition resulting from self-heating.
  • Serious Hazard  -  One that can cause death or serious physical harm.
  • Smoke  -  A visible suspension in air of solid and/or liquid particles resulting from incomplete combustion.
  • Smoke Barrier  -  Consists of walls, partitions, floors and openings that will prevent transmission of smoke or gases through the construction.
  • Smoke Compartment  -  A spacewithin a building enclosed by smpke barriers on all sides, top and bottom.
  • Supervisor  -  A person held responsible for the behavior and production of a group of employees.
  • Supervisor Safety Responsibilities  -  Creating an atmosphere in which safety and environmental issues can be proactively discussed and resolved.   


  • Tagout  -  The placement of a tagout device on an energy isolating device, in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed.
  • Tagout Device  -  A prominent warning device, such as a tag and a means of attachment, which can be securely fastened to an energy isolating device in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed. The tagout device must contain the name of the employee and the date the tag was applied to the device.
  • Total Case Incident Rate  -  The number of work-related injuries per 100 full-time workers during a one year period.
  • Turnkey  -  A product or service that is built, designed, installed, or supplied fully complete and ready to produce or serve.


  • Unsafe Condition  -  A condition that is unsafe and if not corrected is likely to result in injury, death or property damage.
  • Upper Explosive Limit  -  The maximum concentration of vapor or gas in air above which propagation of flame does not occur on contact with a source of ignition.
  • Upper Flammable Limit  -  The maximum concentration of vapor or gas in air above which propagation of flame does not occur on contact with a source of ignition.


  • Vulnerability  -  The physical feature or attribute that renders values susceptible to a given hazard.



  • Workplace Hazard  -  Any source of potential damage, harm, or adverse health effect on something or someone.
  • Workplace Safety  -  The working environment at a company, that includes the health, safety, and well-being of it's employees.



Piping Designer Logo 1

Display #
Authorized Employee
Business Partner Safety Responsibilities
Days Away, Restricted, or Transferred
Employee Safety Responsibilities
Energy Isolating Device
Extension Cords
Flange Safety Spray Shield
Hazardous Atmosphere
Hazardous Energy Control
Injury Frequency Rate

Tags: Safety Engineering