KSE Professional Engineer key terms

The ratio of a structure's or component's ultimate capacity to the maximum load or stress it is expected to carry in service. It accounts for uncertainty in loads, material properties, and analysis methods.

The stress at which a material begins to deform permanently, marking the transition from elastic to plastic behaviour. It is a primary design property for ductile metals such as structural steel.

The maximum engineering stress a material can sustain before necking and fracture during a tension test. It is reported as the peak of the stress-strain curve and is not the same as yield strength.

A plot of applied stress against resulting strain for a material under load. Its elastic region, yield point, strain hardening, and fracture point reveal stiffness, strength, and ductility.

The slope of the linear elastic portion of a stress-strain curve, describing a material's stiffness. Also called Young's modulus, it is used to compute elastic deformation under service loads.

A design method that verifies a structure against specified ultimate and serviceability limit states using factored loads and factored resistances. It replaces a single global safety factor with partial factors.

A design approach in which computed service stresses must not exceed a permissible stress obtained by dividing material strength by a factor of safety. It is also called working stress design.

A defined arrangement of simultaneous load effects, such as dead, live, wind, and seismic, multiplied by load factors. Design codes specify which combinations must be checked for strength and serviceability.

The permanent, self-weight loading on a structure, including structural members, finishes, and fixed equipment. Its magnitude is usually calculated from material densities and is treated as constant over the design life.

A variable load produced by occupancy, use, or movable equipment, such as people, furniture, or stored goods. Design codes prescribe characteristic values that depend on the intended occupancy or use of the space.

A design condition concerning fitness for normal use rather than structural safety, covering deflection, vibration, and crack width. Exceeding it does not cause collapse but may impair function or appearance.

The displacement of a structural element from its unloaded position under applied loads. It is checked against code or project limits to ensure serviceability, drainage, and the performance of supported finishes.

Progressive damage and possible failure of a material caused by repeated or fluctuating stress cycles below its static strength. It is assessed using stress range, cycle count, and detail category S-N data.

A local increase in stress near a geometric discontinuity such as a hole, notch, or sharp change in section. It is quantified by a stress concentration factor and is significant in fatigue-sensitive details.

A material property describing its resistance to propagation of an existing crack under load, commonly expressed as critical stress intensity. It is central to fitness-for-service and flaw assessment.

The ratio of useful work or energy output to energy input for a cycle or device, such as a heat engine or pump. It is bounded by the Carnot limit for heat engines operating between given temperatures.

The ratio of actual heat transfer in a heat exchanger to the maximum thermodynamically possible transfer between the two fluid streams. It depends on flow arrangement and the number of transfer units.

A dimensionless ratio of inertial to viscous forces in fluid flow, used to predict whether flow is laminar or turbulent and to correlate friction and heat transfer data.

A relationship expressing head loss in pipe flow as a function of friction factor, pipe length and diameter, and velocity head. It is widely used for sizing pipes and assessing pumping requirements.

A manufacturer's plot of pump head, efficiency, and power against flow rate at a given impeller speed. Intersecting it with the system curve identifies the operating point.

A priced or unpriced schedule listing measured quantities of work items, prepared from drawings and specifications. It supports tendering, progress valuation, and cost control on construction projects.

A hierarchical decomposition of project scope into manageable deliverables and work packages. It forms the basis for estimating, scheduling, assigning responsibility, and controlling progress.

A scheduling technique that models activities and dependencies to identify the longest path through the network. Activities on that path have zero float and determine the project duration.

The amount of time an activity can be delayed without delaying the project completion or a subsequent activity. Total float and free float are distinguished in network schedule analysis.

A project control technique comparing planned value, earned value, and actual cost to measure cost and schedule performance. Derived indices forecast completion cost and flag emerging variances.

A formal, documented instruction to modify contract scope, schedule, or price after the agreement is executed. It requires authorization and is recorded to preserve traceability and support claims.

A formal written query issued during design or construction to clarify ambiguous documents, resolve conflicts, or confirm intent. Responses become part of the project record and may lead to change orders.

A detailed fabrication or installation drawing prepared by a contractor or supplier from design documents. It is reviewed for conformance with design intent before manufacture or construction proceeds.

A drawing revised to record the actual constructed configuration, dimensions, and installed equipment at project completion. It supports operation, maintenance, and future modification of the facility.

The systematic management of document identification, revision, distribution, and retention so that only current approved versions are used. It underpins traceability and auditability in engineering organizations.

A structured, documented examination of a design by qualified reviewers at defined stages to verify requirements, identify errors, and confirm interfaces. It may be internal or independent and is recorded as evidence.

Verification confirms that a product meets its specified requirements, while validation confirms it fulfils its intended use. Both are planned activities producing objective evidence of conformity.

A record describing a detected departure from specified requirements, its disposition, and corrective action. It triggers investigation and may require concession, rework, or rejection of the item.

Action taken to eliminate the cause of a detected non-conformity so that it does not recur. It differs from containment or correction, which address only the immediate nonconforming item.

A structured investigation method used to identify the underlying reason a problem occurred, rather than its symptoms. Common techniques include the five-whys, fishbone diagrams, and fault tree analysis.

Documented evidence retained to demonstrate that activities affecting quality were performed to specified requirements. Records must be legible, identifiable, and retrievable for the defined retention period.

Inspection methods such as ultrasonic, radiographic, magnetic particle, and dye penetrant testing that reveal internal or surface defects without damaging the component. Qualification and acceptance criteria are code-specified.

A written document specifying the welding variables and parameters required to produce a sound joint for a given application. It is supported by procedure qualification records and used by qualified welders.

A documented set of technical rules and accepted good practice adopted by a jurisdiction or industry body. Compliance may be mandatory by reference in regulation or contractual by agreement between parties.

A consensus-based technical document establishing requirements, specifications, or test methods for products, processes, or services. Standards become legally binding when referenced by regulation or contract.

The state of conforming to applicable statutes, regulations, permits, and licence conditions governing an engineering activity. Evidence of compliance is typically documented and subject to inspection or audit.

A formal written authorization controlling high-risk work such as hot work, confined-space entry, or isolation of hazardous energy. It records precautions, isolations, and acceptance by authorized signatories.

A procedure for isolating hazardous energy sources and securing them with locks and tags before maintenance or repair. It prevents unexpected energization or release of stored energy that could injure workers.

A method of breaking a task into steps and identifying hazards and controls for each step before work begins. The results are communicated to the work crew and reviewed as conditions change.

A ranked order of risk control measures: elimination, substitution, engineering controls, administrative controls, and personal protective equipment. Higher-ranked controls are preferred because they are more reliable.

The systematic process of recognizing sources of potential harm to people, property, or the environment. It is the first step in risk assessment and informs the selection of control measures.

The process of estimating the likelihood and consequence of identified hazards and evaluating whether risk is tolerable. It determines priorities and the need for additional controls.

A formal process predicting the environmental consequences of a proposed project and identifying mitigation measures before approval. It typically includes public consultation and produces a documented statement for the regulator.

A situation in which a professional's personal, financial, or other interest could improperly influence engineering judgement or decisions. It must be disclosed promptly and managed or avoided.

A failure to exercise the reasonable skill, care, and diligence expected of a competent practitioner in similar circumstances, causing loss. It is judged against accepted professional standards, not outcomes alone.

The degree of skill and diligence a reasonable and competent engineer would exercise under comparable circumstances. It is the benchmark used to judge professional performance and alleged negligence.

The act by which a licensed professional engineer takes legal responsibility for engineering work by applying a signature and seal. It is generally limited to work within the licensee's competence and jurisdiction.

The professional obligation to protect client and employer information from unauthorized disclosure, subject to legal or safety exceptions. It continues after the working relationship ends unless released.

A structured document presenting objectives, methods, results, analysis, and conclusions of an engineering investigation for a defined audience. It must be accurate, traceable, and distinguish facts from opinions.

A document stating the technical requirements a product, material, or work must satisfy, including performance, testing, and acceptance criteria. It is referenced in contracts and used to verify conformity.