Glossary
QEHS terminology, defined.
100 core terms every safety, quality, and environmental program owner encounters, short definitions for skimming, long definitions with sources. Published as schema.org/DefinedTerm for AI-assistant lookup.
Metrics
- Days Away, Restricted, TransferredDART
Rate of cases involving days away, restricted duty, or job transfer.
DART = ((column H + column I cases) × 200,000) / hours worked. Captures OSHA columns H (days away) and I (job transfer or restriction). More severity-weighted than TRIR, less noisy than LTIR.
- Lagging indicator
A reactive metric measuring past performance.
TRIR, LTIR, DART, fatalities, citation counts — all lagging. Useful for benchmarking, weak for steering. Programs that report only lagging indicators to leadership are flying blind.
Related: leading-indicator, trir
- Leading indicator
A proactive metric predicting future performance.
Examples: near-miss rate, inspection closure time, training-currency rate, observation-to-action conversion. Leading indicators let a program steer, not just measure — they change before the lagging indicators they predict.
Related: lagging-indicator, trir
- Lost Time Incident RateLTIR
Cases with days away from work, per 100 FTE per year.
LTIR = (lost-time cases × 200,000) / hours worked. A subset of TRIR that only counts OSHA column H (days away). Useful for comparing across jurisdictions that emphasise lost-time over broader recordability.
- Lost Time Injury Frequency RateLTIFR
Lost-time injuries per million hours worked.
LTIFR = (number of LTIs × 1,000,000) ÷ hours worked. Common in Australia, the UK, and global mining/construction benchmarking. US equivalents normalise to 200,000 hours (100 workers × 2,000 hrs). An LTI is any work-related injury causing at least one full shift of lost time.
- Severity rate
Days lost per recordable incident, measuring injury seriousness.
Severity rate = total days away from work ÷ number of recordable incidents. A low TRIR with a high severity rate signals that rare incidents are serious — a different risk profile than a high TRIR with low severity. Pair with TRIR and leading indicators for a complete picture.
- Total Recordable Incident RateTRIR
Recordable injuries per 100 full-time workers per year.
TRIR = (recordable cases × 200,000) / hours worked. OSHA uses 200,000 as the normalising constant (100 FTE × 2,000 hrs). It is the single most-cited safety metric, but it is a lagging indicator — it measures what already happened.
Related: ltir, dart, leading-indicator
Incidents
- Incident
An unplanned event causing or with potential to cause injury, illness, or damage.
Incident is the umbrella term covering near-misses, first-aid cases, recordable injuries, lost-time injuries, fatalities, and environmental releases. OSHA uses "injury or illness" for work-related recordable incidents.
- Incident Severity Matrix
A grid combining likelihood and consequence to classify incident severity.
Typically a 5×5 or 4×4 matrix. Consequence axes: people (first aid → fatality), environment (no impact → catastrophic), assets ($0 → major loss), reputation (no media → international). Likelihood axes: almost certain, likely, possible, unlikely, rare. The intersecting cell determines severity level (S1–S5), which drives investigation depth, escalation protocol, and reporting requirements.
Related: risk, incident, risk-register
- Near miss
An incident with potential for harm that did not result in injury or damage.
A near-miss is an unplanned event that could have caused injury, illness, or damage but did not. Capturing near-misses is a proxy for organisational safety culture — low report counts signal under-reporting, not a safe site.
Related: incident, leading-indicator
- Near-miss Investigation
A formal review of a near-miss event to identify causes and prevent recurrence.
Near-misses are leading indicators of future incidents — Heinrich's Triangle suggests hundreds occur before a serious injury. A near-miss investigation follows the same methodology as an incident investigation (5-Whys, fishbone, bowtie) but with lower urgency. Reporting culture is the key variable: organisations where near-misses are celebrated, not punished, collect the richest data.
Related: near-miss, rca, five-whys, leading-indicator
- OSHA 300 Log
OSHA-mandated log of work-related injuries and illnesses.
US employers with 11+ employees must maintain the OSHA 300 Log throughout the year. Each entry records: case number, employee name, job title, date, injury/illness type, and outcome (days away, restricted duty, etc.). The companion Form 301 captures per-incident details. The 300A summary is posted 1 Feb – 30 Apr each year.
Risk
- As Low As Reasonably PracticableALARP
The UK regulatory standard for demonstrating risk has been reduced to an acceptable level.
ALARP requires that risks be reduced until the cost of further reduction is grossly disproportionate to the benefit. It sits between broadly acceptable risk (<10⁻⁶/yr fatality) and intolerable risk (>10⁻³/yr). The Health and Safety Executive (HSE) publishes risk tolerability criteria. ALARP is the dominant framework in UK, Australia, and Singapore; the US uses feasibility-based cost-benefit for OSHA standards.
Related: safety-case, lopa, risk
- Bowtie analysis
A risk-visualisation method connecting threats, a top event, and consequences.
A bowtie diagram has a central "top event" with preventive barriers on the left (threats → event) and mitigative barriers on the right (event → consequences). Used heavily in process safety and major-hazard facilities.
- Combustible Dust Explosion
An explosion triggered by airborne combustible dust particles in an enclosed space.
The "dust pentagon" requires: combustible dust, ignition source, oxygen, dispersion, and confinement. Common dusts: wood, grain, sugar, metal, coal, plastic. NFPA 652 (Fundamentals) and commodity-specific standards (NFPA 61, 484, 654, 655, 664) govern. OSHA NEP targets grain handling, food processing, and wood products. Primary explosions often trigger more devastating secondary explosions.
- Critical Control
A control whose failure or absence could lead directly to a fatal or catastrophic event.
The ICMM Critical Control Management (CCM) framework, widely adopted in mining, distinguishes critical controls from supporting controls. Critical controls are subject to more rigorous verification — field checks, dedicated inspections — than routine controls. A critical control failure triggers immediate work stoppage regardless of residual risk assessment. The CCM framework is aligned with ISO 45001 risk management.
Related: control-hierarchy, bowtie, inherent-risk
- Failure Mode and Effects AnalysisFMEA
A structured analysis of how components can fail and the effect of each failure.
FMEA assigns a Risk Priority Number (RPN = Severity × Occurrence × Detectability) to each failure mode. High-RPN modes get corrective action priority. DFMEA covers product design; PFMEA covers manufacturing process. Required by IATF 16949 for automotive suppliers and common in aerospace (AS9100) and medical device contexts.
- Fault Tree AnalysisFTA
A top-down, deductive failure analysis using Boolean logic to map causes.
Starting from a defined undesired event (the "top event"), FTA traces backward through AND/OR logic gates to identify combinations of basic events (equipment failures, human errors) that could cause it. Used in process safety, aerospace, and nuclear contexts. Complements FMEA, which works bottom-up.
- Hazard
Any source of potential damage, harm, or adverse health effects.
Hazard is the source (e.g. moving machinery). Risk is the combination of likelihood and consequence when exposed to the hazard. Programs control risk by removing or isolating the hazard, not by warning about it.
Related: risk, jha, control-hierarchy
- Hazard and Operability StudyHAZOP
A structured review of a process using guide-words to find deviations.
A team-based PHA technique that walks the process design, applying guide-words (No, More, Less, Reverse, Other Than, etc.) to each parameter (flow, temperature, pressure, level) to identify deviations, causes, consequences, and safeguards.
- Hazard Identification StudyHAZID
A structured workshop identifying hazards at the earliest design stage.
HAZID is typically the first risk review in a new project, conducted before detailed engineering. A multi-disciplinary team systematically considers categories (fire, explosion, toxic release, structural, environmental) and identifies hazards, consequences, and safeguards. Results feed the project hazard register.
Related: hazop, hazard, risk-register
- Hierarchy of Controls
The ranked order of effectiveness for controlling workplace hazards.
NIOSH and ISO 45001 recognise five levels: (1) Elimination — remove the hazard entirely; (2) Substitution — replace with a less hazardous alternative; (3) Engineering controls — isolate people from the hazard; (4) Administrative controls — change the way people work; (5) PPE — protect the individual. More effective controls are at the top. PPE is a last resort, not a primary control.
- Inherent risk
The raw risk level before any controls are applied.
Inherent risk = likelihood × consequence, assessed as if no controls exist. It represents the true hazard potential of an activity. Organisations use it to prioritise resources — high inherent risk scenarios warrant robust control frameworks even if current residual risk is acceptable, because control failure could be catastrophic.
Related: residual-risk, risk, risk-register
- Job Safety AnalysisJSA
A step-by-step breakdown of a task identifying hazards at each step.
Functionally equivalent to a JHA. The term JSA is common in Australian and Canadian workplaces; JHA is more common in US OSHA contexts. The output is a written document: task steps, associated hazards, recommended controls. JSA completion before high-risk work is a common procedural requirement.
Related: jha, ptw, control-hierarchy
- Job Safety and Environmental AnalysisJSEA
A JHA that explicitly includes environmental hazards alongside safety hazards.
JSEA is common in mining, oil and gas, and utilities, where spills, soil contamination, and noise are material alongside personal safety risks. Each task step is evaluated for both safety AND environmental consequences, and controls are specified for both. Integrating safety and environment in a single document reduces form fatigue and improves field compliance.
- Layers of Protection AnalysisLOPA
A semi-quantitative method for evaluating whether risk reduction is adequate.
LOPA assigns a probability of failure on demand (PFD) to each independent protection layer (IPL) and calculates mitigated event frequency. If the mitigated frequency exceeds the tolerable risk target, additional layers — often a Safety Instrumented System (SIS) — are required. LOPA is the primary method for determining SIL requirements per IEC 61511.
- Residual risk
The risk remaining after controls are applied.
Residual risk = inherent risk adjusted for the effectiveness of controls in place. ISO 45001 requires organisations to determine whether residual risk is acceptable (tolerable) or requires further action. A risk register typically records both inherent and residual scores for each entry. Residual risk is the basis for management decisions on further treatment.
Related: inherent-risk, risk, risk-register
- Risk
The combination of likelihood and consequence of harm from a hazard.
ISO 31000 defines risk as the effect of uncertainty on objectives. In QEHS practice, risk is calculated as Likelihood × Consequence, often on a 5×5 matrix with named thresholds (Low / Medium / High / Critical).
Related: hazard, risk-register, bowtie
- Risk register
A living list of identified risks with owners, controls, and review dates.
Core artefact of any risk-based management system. Typical columns: risk description, category, likelihood, consequence, risk score, controls, residual score, owner, review date. Periodic review — usually quarterly — keeps it live.
- Safety Case
A structured argument, supported by evidence, that a system is acceptably safe.
Required for major hazard facilities in the UK (COMAH), Australia (MHF regulations), and offshore installations (Safety Case Regulations 2015). A safety case demonstrates that all major accident hazards have been identified and risks reduced ALARP (As Low As Reasonably Practicable). It is a living document, updated after significant changes. Differs from a PHA in that it makes a formal safety argument to the regulator.
- Safety Instrumented FunctionSIF
A specific safety function implemented by a Safety Instrumented System.
A SIF is defined by its sensors, logic solver, and final elements (e.g., shut-off valve). Each SIF has an assigned SIL. Examples: high-pressure shutdown, emergency depressurisation, burner management system trip. The full collection of SIFs in a facility forms the Safety Instrumented System (SIS).
- Safety Integrity LevelSIL
A discrete level (SIL 1–4) defining the reliability required of a safety function.
Defined in IEC 61508 and IEC 61511. SIL 1 requires a PFD of 0.1–0.01; SIL 4 requires 0.0001–0.00001. SIL is determined through LOPA or risk graph methods. Safety Instrumented Systems (SIS) must be designed, verified, and validated to achieve the required SIL. SIL is not a product rating — it is a system-level achievement.
- Task Risk AssessmentTRA
A field-level risk assessment completed immediately before a task.
A TRA (also called a FLRA — Field Level Risk Assessment) is completed by the work crew on-site, immediately before starting work. It accounts for real conditions: weather, crew experience, equipment condition, nearby activities. A TRA supplements — but does not replace — a formal JSA or JHA prepared in advance.
Operations
- Behavior-Based SafetyBBS
A proactive safety approach focusing on observing and reinforcing safe behaviors.
BBS programs use trained observers to conduct structured safety observations, recording safe and at-risk behaviors without blame. Data drives coaching conversations and process improvements. Common frameworks: DuPont STOP, ABC (Antecedent–Behavior–Consequence). BBS is most effective when combined with a strong just culture and leading indicator tracking.
Related: leading-indicator, near-miss
- Confined Space Entry
Entry into a space not designed for continuous occupancy with limited egress.
OSHA 29 CFR 1910.146 defines permit-required confined spaces as those with a serious hazard (atmospheric, engulfment, entrapment, or other). Entry requires: atmospheric testing (O2, LEL, toxic gases), isolation and lockout of energy and fluids, a written entry permit, an attendant outside, and a rescue plan. NFPA 350 provides additional guidance.
- Contractor Management
Processes for pre-qualifying, onboarding, and monitoring third-party workers.
Host employers retain liability for contractor safety under OSHA Multi-Employer Citation Policy. A robust programme covers: pre-qualification (insurance, safety stats, training records), site orientation, PTW integration, performance monitoring (observations, incidents), and periodic re-evaluation. PSM sites have explicit contractor management requirements under 29 CFR 1910.119(h).
- Emergency Response PlanERP
A documented plan for responding to foreseeable emergency scenarios.
OSHA 29 CFR 1910.38 requires an Emergency Action Plan for all workplaces; OSHA 29 CFR 1910.119 imposes additional requirements for PSM sites. An ERP covers: evacuation routes, assembly points, emergency contacts, shutdown procedures, fire response, chemical release, medical emergencies, and communication protocols. Annual drills are standard; post-drill reviews drive continuous improvement.
- Hazard Communication StandardHazCom
OSHA's right-to-know standard requiring chemical labelling and SDS availability.
OSHA 29 CFR 1910.1200 (HazCom 2012) aligns the US with the GHS. Requirements: written program, chemical inventory, SDS for every hazardous chemical, GHS-compliant labels, and employee training. HazCom violations are among the most frequently cited OSHA standards.
- Hot Work Permit
A permit authorising activities that produce sparks, flame, or heat near flammable materials.
Hot work includes welding, cutting, grinding, brazing, and soldering. Before a hot work permit is issued, the area is tested for flammable atmosphere (LEL), combustibles are removed or shielded, fire watch is assigned, and extinguishers are staged. The permit specifies location, duration, and required precautions. Post-work fire watch continues for a defined period (commonly 30–60 min).
- Job Hazard AnalysisJHA / JSA
A step-by-step breakdown of a task with hazards and controls per step.
Also called Job Safety Analysis (JSA) or Safe Work Method Statement (SWMS) in some jurisdictions. Structure: task steps → hazards per step → controls per step → residual risk. Most useful when reviewed on-site by the crew performing the work.
- Lock-Tag-Try
The three-step verification that energy isolation is complete before working on equipment.
After applying lockout/tagout devices, the worker must attempt to activate the equipment ("try") to confirm all energy sources are isolated and the equipment cannot be energised. This is the critical last step of LOTO that prevents accidents from incomplete isolation. OSHA cites LOTO violations as one of the top 10 most frequently cited standards annually.
- Lockout / TagoutLOTO
Isolating hazardous energy during servicing and maintenance.
OSHA 29 CFR 1910.147 requires identification of energy sources (electrical, hydraulic, pneumatic, thermal, mechanical, chemical, gravity), application of locks/tags, verification of zero-energy state ("try-out"), and documented return-to-service.
Related: ptw, energy-isolation
- Management of ChangeMOC
A structured process for evaluating changes before they are implemented.
A PSM element (1910.119(l)) and an ISO expectation. Captures the technical basis of the change, affected procedures, training needs, and authorising approvals before execution. Skipping MOC is one of the most common root causes in major-hazard incidents.
- Material Safety Data SheetMSDS
The legacy 8-section chemical information sheet, replaced by the 16-section SDS.
MSDS was the pre-GHS term for chemical safety documents. Since the 2012 HazCom revision, "SDS" (Safety Data Sheet) is the correct term with a standardised 16-section format. Legacy MSDS documents from before the GHS transition may still exist in older facilities and must be updated to the SDS format.
- Permit to workPTW
A formal authorisation to perform high-risk work with defined controls.
PTW systems cover hot work, confined space, working at height, energy isolation, excavation, and critical lifts. The permit captures the controls agreed between requestor, authorising person, and operations, and is retained as audit evidence.
Related: hot-work, confined-space, loto, jha
- Permit to Work System
A formal, documented system authorising hazardous work for a defined scope and duration.
A PTW system ensures that all hazards are identified and controlled before work starts, and that multiple work activities are coordinated safely. Types: hot work, confined space entry, working at heights, electrical isolation, excavation, radiography. The permit is issued by an authorised person, accepted by the work team, and formally closed on completion. PTW failures are implicated in many major industrial disasters.
Related: ptw, hot-work, confined-space, loto
- Personal Protective EquipmentPPE
Equipment worn to minimise exposure to hazards.
OSHA 29 CFR 1910.132 requires a hazard assessment certifying the PPE selected. PPE is the last rung of the hierarchy of controls — elimination, substitution, engineering controls, administrative controls, and PPE.
Related: control-hierarchy, sds
- Pre-Startup Safety ReviewPSSR
A final check before new or modified equipment is put into service.
Required under OSHA PSM 1910.119(i). Verifies that construction matches design, procedures are in place, training is complete, and PHA recommendations are addressed.
- Pre-Startup Safety ReviewPSSR
A structured review confirming a facility or system is safe to start up.
Required by OSHA PSM (29 CFR 1910.119(i)) for new or modified facilities where the change triggers MOC. A PSSR confirms: construction complies with design specs, safety/operating/maintenance/emergency procedures are in place, a PHA has been performed and recommendations addressed, and affected employees have been trained. Sign-off by operations, maintenance, and safety is typical.
- Process Safety ManagementPSM
OSHA's 14-element framework for preventing catastrophic releases of highly hazardous chemicals.
PSM (29 CFR 1910.119) applies when quantities of listed chemicals exceed thresholds. The 14 elements include: PHAs, MOC, PSSR, operating procedures, training, mechanical integrity, hot work permits, incident investigation, emergency response, contractor management, and compliance audits every 3 years. Non-compliance can result in Willful citations and multi-million dollar penalties.
- Safety Culture
The shared values, beliefs, and behaviours that determine how safety is prioritised in an organisation.
Safety culture is often assessed using maturity models (Bradley Curve: reactive → dependent → independent → interdependent). Key dimensions: leadership commitment, worker involvement, just culture (reporting vs. blame), hazard reporting rates, and safety communication. A weak safety culture is the root cause behind most major disasters (Chernobyl, Challenger, Deepwater Horizon). Culture change requires sustained leadership behaviour, not slogans.
Related: bbs, near-miss, leading-indicator
- Safety Data Sheet Management
The process of maintaining current SDS documents for all hazardous chemicals on-site.
OSHA HazCom requires SDSs to be readily accessible to workers during their shifts. An SDS management system tracks: chemical inventory, SDS revision date, storage location, access controls, and superseded versions. When a supplier updates an SDS (e.g., new health data, revised exposure limits), the system must propagate the update and notify affected workers.
- Working at Heights
Any work where a person could fall and be injured.
Regulatory thresholds vary: OSHA general industry ≥4 ft; construction ≥6 ft; OSHA scaffolding ≥10 ft. Controls follow the hierarchy: elimination (working at ground), passive protection (guardrails), fall restraint, fall arrest (full-body harness + lanyard or PFAS), then administrative (rescue plan, supervision). Rescue capability is a mandatory part of any fall arrest programme.
Related: ppe, ptw, control-hierarchy
Standards
- 21 CFR Part 11 — Electronic Records
FDA regulation governing electronic records and electronic signatures.
Applies to electronic records that are required to be created or maintained by FDA regulations, or submitted to FDA. Key requirements: audit trails (time-stamped, user-attributable, computer-generated), access controls, system validation, and electronic signature controls. Non-compliance can invalidate submissions and trigger 483 observations or Warning Letters.
- AS9100 — Aerospace QualityAS9100
The quality management standard for aerospace, space, and defence suppliers.
AS9100 Rev D (2016) layers aerospace-specific requirements onto ISO 9001:2015 — including product/process risk management, configuration management, first article inspection, key characteristics, and FOD (foreign object damage) prevention. Required by Boeing, Airbus, Lockheed Martin, and most aerospace primes. Oversight by IAQG registrars.
- Environmental Management SystemEMS
A structured framework for managing an organisation's environmental responsibilities.
An EMS follows the Plan-Do-Check-Act cycle and is formalised through ISO 14001. Core elements: environmental policy, aspects and impacts assessment, legal register, objectives and targets, operational controls, emergency preparedness, monitoring and measurement, nonconformity management, and management review. An EMS can be certified by an accredited third party or implemented without certification (self-declaration).
Related: iso-14001, environmental-aspect, esg
- Gap Analysis
A structured comparison of current practice against a standard or target state.
A gap analysis maps each requirement of a standard (ISO 9001, 45001, etc.) against evidence of current conformance, rating each clause as conforming, partially conforming, or non-conforming. Results produce a prioritised implementation plan. Typically conducted before a first certification audit or after a significant regulatory change. ISO 9001 Annex C and OSHA VPP self-evaluation tools are common frameworks.
Related: internal-audit, capa, management-review
- IATF 16949 — Automotive QualityIATF 16949
The global quality management standard for automotive production and service parts.
IATF 16949:2016 (developed by IATF, published with ISO 9001:2015 as a foundation) adds automotive-specific requirements: APQP, PPAP, FMEA, MSA, SPC, and customer-specific requirements (CSRs) from OEMs. Required for Tier 1 and often Tier 2 automotive suppliers. Certification is by IATF-recognised CBs; annual surveillance audits are mandatory.
- Internal Audit
A planned, systematic review of a management system by the organisation itself.
ISO 19011 provides guidance on auditing management systems. Internal audits must be: planned (programme covering all processes and areas), competence-based (auditors independent of the area being audited), documented (findings, nonconformities, and opportunities for improvement), and followed up for corrective action closure. Results feed the Management Review.
Related: management-review, ncr, capa
- ISO 14001
Environmental Management System standard.
Most-widely adopted environmental standard globally. Life-cycle perspective on aspects and impacts, compliance obligations register, and emergency preparedness for environmental releases.
- ISO 45001
International standard for Occupational Health and Safety Management Systems.
Published 2018. Replaced OHSAS 18001. Uses the Annex SL high-level structure shared with ISO 9001 and 14001. Ten clauses: Context, Leadership, Planning, Support, Operation, Performance evaluation, Improvement.
- ISO 50001 — Energy Management
The international standard for energy management systems.
ISO 50001:2018 follows the Annex SL high-level structure shared with ISO 9001, 14001, and 45001, enabling integrated management. Core concepts: energy baseline, energy performance indicators (EnPIs), significant energy uses (SEUs), energy objectives, and management review. Certification is voluntary but increasingly required in supply chains and for public-sector procurement.
- ISO 9001
Quality Management System standard.
The most-widely certified management-system standard. Customer focus, process approach, risk-based thinking, and the PDCA cycle as operating philosophy.
- Legal and Other Requirements Register
A living list of applicable laws, regulations, and voluntary commitments relevant to EHS.
ISO 14001 and ISO 45001 both require organisations to identify and maintain access to applicable legal requirements. The register typically captures: regulation reference, jurisdiction, applicable activities, compliance obligations, responsible person, and evidence of compliance. Annual review and gap analysis against new regulations are standard practice.
Related: iso-45001, iso-14001, gap-analysis
- Management Review
A periodic top-management assessment of a management system's performance.
Required by ISO 9001, 14001, 45001, and 50001. Inputs must include: audit results, nonconformities and CAPAs, performance metrics, customer/stakeholder feedback, and progress on objectives. Outputs must include decisions on resource needs, improvement opportunities, and any changes to the system. Management review records are a mandatory documented information requirement.
- Process Safety ManagementPSM
OSHA 29 CFR 1910.119 — 14 elements preventing major process incidents.
Applies to processes containing threshold quantities of highly hazardous chemicals. Requires PHA, written procedures, training, contractors program, PSSR, mechanical integrity, hot-work permit, MoC, incident investigation, emergency planning, and compliance audits every three years.
Quality
- Corrective and Preventive ActionCAPA
Actions taken to fix a nonconformity and prevent its recurrence.
CAPA separates corrective action (eliminate the cause of the detected nonconformity) from preventive action (eliminate the cause of a potential nonconformity). ISO 9001:2015 uses CAPA as part of clauses 10.2 (nonconformity) and 10.3 (improvement).
- Fishbone / Ishikawa
Cause-and-effect diagram grouping causes by category.
Also called the Ishikawa diagram. Cause categories commonly include Man, Method, Machine, Material, Measurement, Environment (the 6 Ms / 6 Es). Better suited to multi-cause problems than Five Whys.
- Five Whys
Iterative asking of "why" to trace a cause chain.
Developed at Toyota. Repeatedly ask "why did this happen?" — typically five iterations are enough to cross from symptom to cause. Works best for single-fault-path problems, less well for systemic issues where multiple causes interact.
- Gemba Walk
A leadership practice of going to the actual workplace to observe and engage.
"Gemba" (現場) means "the actual place" in Japanese — the shop floor, the worksite, the clinic, wherever the value-creating work happens. A structured gemba walk follows a standard observation sheet covering safety, quality, delivery, and housekeeping. It is not a management inspection; questions are open-ended and the goal is learning, not fault-finding.
Related: bbs, kaizen, leading-indicator
- Kaizen
Japanese for "change for the better" — continuous, incremental improvement.
Kaizen events (3–5 day focused improvement workshops, also called "blitzes") bring cross-functional teams together to eliminate waste in a targeted process. Sustained kaizen is a culture, not just events — every employee, every day, improving their work. Kaizen is a foundational element of the Toyota Production System and Lean manufacturing.
- Nonconformity ReportNCR
A record of a product, process, or system that does not meet a requirement.
Used in ISO 9001 quality programs and regulated industries. Each NCR is linked to a CAPA for containment, correction, and preventive action.
- Pareto Analysis
The 80/20 rule applied to quality defects — 80% of problems from 20% of causes.
Pareto analysis ranks defect categories by frequency or cost, cumulating until 80% of the total is explained. The resulting Pareto chart (bar + cumulative line) shows which few causes account for most defects, directing corrective action effort. A standard tool in Six Sigma DMAIC and ISO 9001 continual improvement cycles.
- Root Cause AnalysisRCA
A structured method to find the underlying cause of a problem.
Common methods: Five Whys (iterative questioning), Fishbone / Ishikawa (cause categories), Fault Tree Analysis, and Apollo RCA. The output is a cause chain, not a list of symptoms. The usefulness of an RCA is measured by whether the CAPA it produces prevents recurrence.
- Six Sigma
A data-driven improvement methodology targeting 3.4 defects per million opportunities.
Six Sigma uses the DMAIC cycle (Define, Measure, Analyse, Improve, Control) for improvement projects and DMADV for new designs. Practitioners are certified at White, Yellow, Green, Black, and Master Black Belt levels. Motorola originated it; GE popularised it. When combined with Lean (waste elimination), the result is Lean Six Sigma — the dominant manufacturing excellence framework.
- Statistical Process ControlSPC
The use of control charts to monitor process variation and detect abnormalities.
SPC distinguishes common-cause variation (inherent, random) from special-cause variation (assignable, non-random). Control limits (±3σ) are calculated from process data, not specifications. When special causes appear (points outside limits, trends, patterns), investigation and corrective action are triggered. Core IATF 16949 requirement; also used in pharmaceutical, food, and aerospace quality.
Health
- Globally Harmonized SystemGHS
UN-harmonised system for classifying and labelling chemicals.
GHS standardises hazard classification (physical, health, environmental), label elements (pictogram, signal word, hazard statement, precautionary statement), and SDS format. Adopted by OSHA HazCom 2012 in the US.
- Heat Stress
The physiological strain imposed by a hot environment exceeding the body's cooling capacity.
Heat stress disorders range from heat cramps and syncope to heat exhaustion and heat stroke (a medical emergency). Wet Bulb Globe Temperature (WBGT) is the standard exposure metric. OSHA has proposed a heat rule (29 CFR 1910/1926) requiring heat illness prevention programmes, rest/water/shade, and acclimatisation schedules. ACGIH publishes TLVs for heat stress.
Related: ppe, leading-indicator, tlv
- Indoor Air QualityIAQ
The quality of air inside buildings affecting occupant health and comfort.
IAQ concerns: CO2 (indicator of ventilation adequacy; ASHRAE 62.1 targets <1,000 ppm), VOCs, particulates, biological contaminants (mould, Legionella, allergens), and radon. OSHA has no comprehensive IAQ standard but enforces under the General Duty Clause. NIOSH IAQ investigations are a frequent response to "sick building" complaints.
Related: legionella, hazard, tlv
- Legionella Risk Assessment
Assessment and control of Legionella bacteria in water systems.
Legionella pneumophila thrives in water at 20–45 °C, especially in stagnant, scale-laden systems. Risk sites: cooling towers, hot water systems, decorative fountains, dental units. Control: maintain hot water >60 °C, cold <20 °C, regular disinfection, and routine sampling. In the UK, HSE ACoP L8 and HTM 04-01 are the standards. CDC MMWR guidance applies in the US.
- Lower Explosive LimitLEL
The minimum concentration of a gas in air at which ignition can occur.
Below the LEL, the mixture is too lean to ignite. Above the UEL (Upper Explosive Limit), it is too rich. Gas detectors typically alarm at 10% LEL (action level) and 25% LEL (evacuation). Oxygen deficiency (<19.5%) can suppress combustion while still being immediately dangerous to life.
Related: hot-work, confined-space, sds
- Noise Exposure / Hearing Conservation
Occupational noise management to prevent noise-induced hearing loss.
OSHA 29 CFR 1910.95 requires a Hearing Conservation Programme when noise exposure reaches 85 dBA TWA (Action Level). Components: noise monitoring, audiometric testing, hearing protector provision, training, and recordkeeping. Engineering controls (enclosures, vibration damping) are preferred over PPE. NIOSH recommends 85 dBA as the REL; OSHA's PEL is 90 dBA.
- Permissible Exposure LimitPEL
OSHA's legally enforceable occupational exposure limits.
PELs are codified in 29 CFR 1910.1000 (Z-tables) and substance-specific standards (e.g., 1910.1025 for lead). Most PELs were adopted from 1968 ACGIH TLVs and have not been updated, making many inadequate by modern toxicological standards. Employers are encouraged to use more current TLVs or NIOSH RELs as voluntary targets.
- Rapid Entire Body AssessmentREBA
An ergonomic tool assessing whole-body posture for musculoskeletal risk.
REBA extends RULA to include lower body postures and is better suited for dynamic, unpredictable tasks (healthcare patient handling, construction). Scores 1–15 map to risk levels from negligible to very high. Often used alongside NIOSH Lifting Equation for manual handling tasks.
Related: rula, leading-indicator
- Rapid Upper Limb AssessmentRULA
An ergonomic assessment tool scoring upper body posture and muscle use.
RULA assigns scores to upper arm, forearm, wrist, neck, trunk, and leg postures, plus muscle use and force. The final score (1–7) indicates the level of intervention required: 1–2 acceptable, 5–6 investigate soon, 7 investigate immediately. Widely used in office, manufacturing, and healthcare ergonomics programmes.
Related: reba, leading-indicator
- Safety Data SheetSDS
16-section document describing a chemical hazard and its controls.
OSHA HazCom 2012 adopted the GHS 16-section format: Identification, Hazard identification, Composition, First-aid, Fire-fighting, Accidental release, Handling and storage, Exposure controls / PPE, Physical and chemical properties, Stability and reactivity, Toxicological information, Ecological information, Disposal, Transport, Regulatory, Other.
- Threshold Limit ValueTLV
ACGIH occupational exposure guideline values for airborne contaminants.
Published annually by the American Conference of Governmental Industrial Hygienists (ACGIH). Three types: TLV-TWA (8-hr time-weighted average), TLV-STEL (15-min short-term exposure limit), and TLV-C (ceiling, never exceeded). TLVs are not regulatory limits (PELs are); however, they are often more current and health-protective than OSHA PELs.
Related: pel, sds, noise-exposure
Environment
- Cradle-to-Grave Waste Tracking
Generator accountability for hazardous waste from generation to final disposal.
Under RCRA, hazardous waste generators remain legally responsible for their waste until it is properly treated, stored, or disposed of. This is enforced through the Uniform Hazardous Waste Manifest system, which tracks waste from the generator site through transporters to the permitted Treatment, Storage, and Disposal Facility (TSDF). e-Manifest (EPA myRCRAid) is the electronic manifest system.
- Environmental aspect
An element of an organisation's activities that can interact with the environment.
ISO 14001 requires organisations to identify environmental aspects — fuel combustion, wastewater discharge, chemical storage, noise, land disturbance — and determine which are "significant" based on their actual or potential environmental impact. Significant aspects drive objectives, operational controls, and emergency preparedness. The aspect-impact register is the environmental equivalent of a safety risk register.
Related: iso-14001, esg, risk-register
- Environmental, Social, GovernanceESG
A framework for reporting non-financial sustainability performance.
ESG reporting is distinct from environmental management under ISO 14001, though the two overlap. Common standards: GRI, SASB, TCFD, CSRD (EU), ISSB. QEHS data (emissions, water, waste, injuries, diversity) is frequently the source for ESG disclosures.
Related: iso-14001
- Greenhouse Gas InventoryGHG
A quantified account of greenhouse gas emissions from an organisation.
Governed by the GHG Protocol Corporate Standard. Emissions are organised into Scope 1 (direct combustion, fugitive releases, company vehicles), Scope 2 (purchased electricity/heat/steam), and Scope 3 (supply chain, employee travel, use of sold products). ISO 14064-1 provides an auditable reporting standard. GHG inventories feed ESG disclosures, TCFD reports, and carbon offset programmes.
- PFAS — Per- and Polyfluoroalkyl SubstancesPFAS
A class of synthetic chemicals called "forever chemicals" due to environmental persistence.
PFAS encompass thousands of compounds (PFOA, PFOS, GenX, etc.) used in non-stick coatings, firefighting foam (AFFF), food packaging, and stain repellents. They accumulate in groundwater and living tissue. EPA has set MCLs for PFOA/PFOS at 4 ppt in drinking water (2024). Sites with AFFF use or manufacturing must assess and potentially remediate PFAS contamination.
- REACH — Chemical RegulationREACH
EU regulation requiring registration, evaluation, and restriction of chemical substances.
REACH (EC 1907/2006) places the burden of proof on manufacturers and importers to demonstrate chemical safety. Substances of Very High Concern (SVHCs) are listed on the Candidate List; articles containing SVHCs above 0.1% w/w must be disclosed. Authorisation is required for listed substances; restrictions apply EU-wide.
- Restriction of Hazardous SubstancesRoHS
EU directive restricting hazardous substances in electrical and electronic equipment.
RoHS 3 (EU 2015/863) restricts ten substances including lead, mercury, cadmium, hexavalent chromium, and four phthalates. Applies to EEE placed on the EU market. Manufacturers must issue a Declaration of Conformity and maintain technical documentation for 10 years. Enforcement is by market surveillance authorities.
- Scope 1 emissions
Direct GHG emissions from sources owned or controlled by the organisation.
Scope 1 includes: stationary combustion (boilers, furnaces), mobile combustion (company fleet), process emissions (cement calcination, steelmaking), and fugitive emissions (refrigerant leaks, methane from pipelines). Scope 1 is the most controllable category and the starting point for any decarbonisation roadmap.
- Scope 2 emissions
Indirect GHG emissions from purchased electricity, heat, steam, or cooling.
The GHG Protocol allows two Scope 2 accounting methods: location-based (average grid emissions) and market-based (contract-specific factors from RECs, PPAs, or supplier rates). Market-based Scope 2 can be reduced to zero through renewable energy certificates; location-based reflects actual grid carbon intensity. Both must be disclosed.
- Scope 3 emissions
All other indirect GHG emissions in the value chain, upstream and downstream.
The GHG Protocol defines 15 Scope 3 categories including purchased goods and services, capital goods, fuel/energy-related activities, transportation, waste, business travel, employee commuting, and use/end-of-life of sold products. Scope 3 typically accounts for 70–90% of total corporate footprint, making supply chain engagement critical to net-zero targets.
- Stormwater Pollution Prevention PlanSWPPP
A plan required under NPDES permits to prevent stormwater contamination.
Required for industrial facilities and construction sites under EPA NPDES Multi-Sector General Permit (MSGP) or Construction General Permit (CGP). A SWPPP identifies pollutant sources, describes BMPs (Best Management Practices), and establishes inspection and monitoring schedules. Annual comprehensive site inspections and quarterly visual assessments are typically required.
- Tier II Report — EPCRA Section 312Tier II
Annual chemical inventory report filed with state and local emergency planners.
EPCRA Section 312 requires US facilities storing hazardous chemicals at or above threshold quantities to submit Tier II reports by March 1 each year to the State Emergency Response Commission (SERC), Local Emergency Planning Committee (LEPC), and local fire department. Reports include chemical name, CAS#, quantity, storage locations, and physical/health hazards.
- TRI Form R — Toxic Release InventoryForm R
Annual EPA report on releases and transfers of listed toxic chemicals.
EPCRA Section 313 requires US facilities meeting SIC code, employee, and threshold criteria to file Form R (or the abbreviated Form A) by July 1 for the prior calendar year. Reports cover on-site releases to air, water, and land, plus off-site transfers for disposal or recycling. Data is published in the EPA TRI National Analysis and accessible via the TRI Explorer database.