This glossary explains key terminology used across Business Services / Professional Services, with a focused reference for the EHS & Safety Consulting Services Practice. It helps executives, consultants, and operational leaders interpret regulations, risk controls, management systems, credentials, exposure limits, and performance measures.
A B C D E F G H I J L M N O P Q R S T U V W X
| A | |
| AAI | All Appropriate Inquiries: A U.S. environmental due-diligence process used to evaluate a property’s prior ownership and uses before acquisition. Meeting the applicable requirements can support certain protections from federal contaminated-site liability. |
| ACGIH | American Conference of Governmental Industrial Hygienists: A scientific association that publishes widely used occupational exposure guidelines, including airborne limits and biological exposure benchmarks. |
| ACM | Asbestos-Containing Material: Material containing more than the regulated threshold of asbestos. Identification and condition assessment are essential for renovation planning, exposure control, abatement, and regulatory compliance. |
| AED | Automated External Defibrillator: A portable device that analyzes heart rhythm and can deliver a shock during sudden cardiac arrest. Workplace programs address placement, inspection, training, and emergency-response integration. |
| AFFF | Aqueous Film-Forming Foam: A firefighting foam designed for flammable-liquid fires. Legacy formulations may contain persistent fluorinated chemicals, creating important handling, replacement, remediation, and disposal considerations. |
| AFR | Accident Frequency Rate: A lagging safety metric that normalizes accident counts by hours worked or another exposure basis. Organizations must state the calculation convention because multipliers vary by jurisdiction and industry. |
| AHERA | Asbestos Hazard Emergency Response Act: A U.S. federal law requiring schools to inspect for asbestos-containing building materials and maintain management plans. It also establishes requirements affecting response actions and accredited personnel. |
| AHJ | Authority Having Jurisdiction: The organization or official responsible for interpreting and enforcing a code, standard, or approval requirement. The responsible authority may be a fire marshal, labor agency, building official, insurer, or other designated body. |
| AIHA | American Industrial Hygiene Association: A professional association supporting occupational and environmental health practitioners through technical guidance, education, laboratory accreditation programs, and exposure-assessment resources. |
| ALARA | As Low As Reasonably Achievable: A radiation-protection principle requiring exposures to be reduced below regulatory limits when practical, considering technology, economics, and societal factors. |
| ALARP | As Low As Reasonably Practicable: A risk-reduction principle under which additional controls are required unless their cost, time, or effort is grossly disproportionate to the further risk reduction achieved. |
| ANSI | American National Standards Institute: The U.S. coordinator for voluntary consensus standards and conformity-assessment systems. Its accredited standards frequently inform workplace safety programs, equipment specifications, and recognized industry practice. |
| APF | Assigned Protection Factor: The expected level of respiratory protection provided by a properly functioning respirator when used within a compliant program. It helps determine whether a respirator is suitable for a measured or anticipated exposure. |
| APR | Air-Purifying Respirator: A respirator that removes contaminants from ambient air through filters, cartridges, or canisters rather than supplying clean air. Selection depends on the contaminant, concentration, oxygen level, and cartridge limitations. |
| AQI | Air Quality Index: A public-health scale that translates ambient pollutant concentrations into categories of health concern. It supports outdoor-work decisions during smoke, ozone, and particulate pollution events. |
| ASP | Associate Safety Professional: A credential from the Board of Certified Safety Professionals demonstrating foundational competence in professional safety practice. It is also a common pathway toward the certified safety professional designation. |
| ASSP | American Society of Safety Professionals: A professional association that develops technical resources, education, and consensus standards for occupational safety and health practitioners. |
| AST | Aboveground Storage Tank: A tank situated above ground or otherwise meeting the applicable regulatory definition. Compliance programs commonly address integrity, secondary containment, inspections, overfill prevention, and spill planning. |
| ATEX | Atmosphères Explosibles (Explosive Atmospheres): The European Union framework governing equipment used in potentially explosive atmospheres and worker protection in those areas. It drives hazardous-area classification, equipment selection, and ignition-risk controls. |
| ATSDR | Agency for Toxic Substances and Disease Registry: A U.S. public-health agency that evaluates health effects associated with hazardous-substance releases. Its toxicological profiles and health consultations support exposure and community-risk assessments. |
| B | |
| BACT | Best Available Control Technology: A case-specific air-emissions limitation applied to certain new or modified major sources under U.S. permitting programs. The determination considers technical feasibility, energy, environmental impacts, and cost. |
| BBP | Bloodborne Pathogens: Disease-causing microorganisms present in human blood and certain other bodily fluids. Exposure-control plans address tasks, engineering controls, work practices, vaccination, training, and post-exposure response. |
| BBS | Behavior-Based Safety: An approach that uses observation and feedback to reinforce safe behaviors and identify barriers to safe work. Effective programs complement rather than replace engineering controls, system improvements, and leadership accountability. |
| BCSP | Board of Certified Safety Professionals: A credentialing body that administers professional certifications across safety, health, and environmental disciplines. |
| BEI | Biological Exposure Indices: Guidance values for chemicals or metabolites measured in biological specimens. They supplement air monitoring by helping assess total uptake through inhalation, skin absorption, ingestion, and other routes. |
| BGC | Board for Global EHS Credentialing: A credentialing organization for industrial hygiene, environmental auditing, and related professional disciplines. It administers designations including certified industrial hygienist and certified professional environmental auditor. |
| BLEVE | Boiling Liquid Expanding Vapor Explosion: A violent vessel failure that occurs when a pressurized liquid above its normal boiling point is suddenly released. It is a major scenario in fire protection, emergency planning, and process hazard analysis. |
| BMP | Best Management Practice: An operational, structural, or administrative measure used to prevent or reduce environmental releases. Permit programs frequently require documented practices for stormwater, erosion, waste, and spill control. |
| BOD | Biochemical Oxygen Demand: A measure of the oxygen microorganisms consume while decomposing organic matter in water. It is a core parameter for wastewater treatment performance and discharge compliance. |
| BPCS | Basic Process Control System: The control hardware and software used to operate a process within normal parameters. Its independence from protective systems is important when assigning credit to risk-reduction layers. |
| BSC | Biological Safety Cabinet: A ventilated enclosure designed to protect personnel, products, and the environment during biological work. Proper selection, placement, certification, and work practices are essential to containment. |
| BSL | Biosafety Level: One of four containment levels defining laboratory practices, safety equipment, and facility controls for biological agents. The assigned level reflects the agent’s hazards and routes of transmission. |
| C | |
| CAA | Clean Air Act: The principal U.S. federal law governing air pollution from stationary and mobile sources. It underpins air-quality standards, permitting, emissions controls, hazardous-pollutant rules, and enforcement. |
| Cal/OSHA | California Division of Occupational Safety and Health: The state agency that administers and enforces California workplace safety and health requirements, many of which are more stringent or specific than federal rules. |
| CAOHC | Council for Accreditation in Occupational Hearing Conservation: An organization that establishes training and certification standards for personnel conducting occupational hearing tests and supporting hearing-conservation programs. |
| CAPA | Corrective and Preventive Action: A structured process for correcting identified deficiencies, addressing root causes, and preventing recurrence or similar failures. It supports audit closure, incident follow-up, and management-system improvement. |
| CAS RN | Chemical Abstracts Service Registry Number: A unique numerical identifier assigned to a chemical substance. It reduces ambiguity when reviewing inventories, safety data, exposure limits, and regulatory lists. |
| CBRN | Chemical, Biological, Radiological, and Nuclear: A collective term for high-consequence hazards requiring specialized detection, protective equipment, decontamination, emergency response, and consequence-management capabilities. |
| CCPS | Center for Chemical Process Safety: An American Institute of Chemical Engineers organization that develops widely used guidance on process safety management, hazard analysis, barrier performance, and major-incident prevention. |
| CDM | Construction (Design and Management) Regulations: United Kingdom regulations assigning health and safety duties to clients, designers, principal designers, contractors, and principal contractors throughout construction projects. |
| CEMS | Continuous Emissions Monitoring System: Instrumentation that continuously measures specified pollutants, diluents, or operating parameters in an exhaust stream. Reliable data are critical for permit compliance, reporting, and control-system performance. |
| CERCLA | Comprehensive Environmental Response, Compensation, and Liability Act: The U.S. federal law governing releases and cleanup of hazardous substances at contaminated sites. It establishes broad liability provisions and the federal Superfund program. |
| CFR | Code of Federal Regulations: The codification of general and permanent rules issued by U.S. federal agencies. Environmental and workplace requirements are commonly referenced by title, part, and section within this code. |
| CHMM | Certified Hazardous Materials Manager: A professional credential demonstrating competence in hazardous-materials management, environmental protection, safety, transportation, and regulatory compliance. |
| CHST | Construction Health and Safety Technician: A Board of Certified Safety Professionals credential for practitioners who identify and control health and safety hazards on construction projects. |
| CIH | Certified Industrial Hygienist: A professional credential demonstrating expertise in anticipating, recognizing, evaluating, and controlling occupational health hazards. |
| CO2e | Carbon Dioxide Equivalent: A common unit that expresses the warming effect of different greenhouse gases relative to carbon dioxide. It enables aggregation of emissions inventories and comparison of reduction initiatives. |
| COD | Chemical Oxygen Demand: A measure of the oxygen equivalent needed to chemically oxidize substances in water. It provides a rapid indicator of wastewater strength and treatment performance. |
| COMAH | Control of Major Accident Hazards Regulations: United Kingdom regulations requiring facilities with threshold quantities of dangerous substances to prevent major accidents and limit their consequences for people and the environment. |
| COSHH | Control of Substances Hazardous to Health Regulations: United Kingdom regulations requiring employers to assess and control worker exposure to hazardous substances through prevention, engineering controls, procedures, monitoring, and health surveillance. |
| CPEA | Certified Professional Environmental Auditor: A professional credential for practitioners who evaluate environmental, health, safety, and management-system compliance and performance. |
| CPR | Cardiopulmonary Resuscitation: An emergency procedure using chest compressions, often with rescue breathing, to maintain circulation during cardiac arrest. Training is a foundational element of many workplace first-aid programs. |
| CREC | Controlled Recognized Environmental Condition: A recognized environmental condition resulting from a past release that has been addressed but remains subject to required controls or restrictions. It is a specific classification in Phase I property assessments. |
| CSP | Certified Safety Professional: A widely recognized credential demonstrating advanced competence in professional safety practice, risk control, emergency preparedness, management systems, and related disciplines. |
| CWA | Clean Water Act: The principal U.S. federal law governing pollutant discharges to surface waters. It establishes permitting, water-quality, spill-prevention, stormwater, and enforcement requirements. |
| D | |
| DART | Days Away, Restricted, or Transferred: A recordable-injury metric covering cases involving time away from work, restricted duty, or job transfer. The normalized rate helps compare performance across periods and workforces of different sizes. |
| dB | Decibel: A logarithmic unit used to express sound-pressure level and other ratios. Small numerical changes can represent substantial changes in sound energy and exposure. |
| dBA | A-Weighted Decibel: A sound-level unit adjusted to approximate human hearing sensitivity across frequencies. It is commonly used for occupational noise exposure limits and hearing-conservation decisions. |
| DHA | Dust Hazard Analysis: A systematic evaluation of combustible-dust hazards, credible fire and explosion scenarios, safeguards, and recommended actions. It is central to managing dust-producing processes and facilities. |
| DNAPL | Dense Non-Aqueous Phase Liquid: A liquid contaminant that does not readily mix with water and is denser than water, allowing it to migrate below the water table. Its behavior can make site investigation and remediation particularly difficult. |
| DOT | United States Department of Transportation: The federal department regulating the classification, packaging, marking, documentation, and transport of hazardous materials across covered modes. |
| DSEAR | Dangerous Substances and Explosive Atmospheres Regulations: United Kingdom regulations requiring employers to assess and control fire, explosion, and corrosion risks created by dangerous substances in the workplace. |
| E | |
| EAP | Emergency Action Plan: A documented plan defining alarms, reporting, evacuation, sheltering, accountability, and employee responsibilities during foreseeable emergencies. |
| EHS | Environment, Health, and Safety: The organizational discipline responsible for protecting workers, communities, and the environment while maintaining compliance and controlling operational risk. |
| EHSMS | Environment, Health, and Safety Management System: A structured framework of policies, responsibilities, procedures, objectives, controls, assurance activities, and reviews used to manage risk and improve performance. |
| EMR | Experience Modification Rate: An insurance factor comparing an employer’s workers’ compensation loss experience with expected losses for similar organizations. It can influence premiums, contractor qualification, and management attention. |
| EMS | Environmental Management System: A formal framework for identifying environmental aspects, meeting obligations, setting objectives, controlling operations, auditing performance, and driving continual improvement. |
| EPA | United States Environmental Protection Agency: The federal agency responsible for administering and enforcing major U.S. environmental laws governing air, water, waste, chemicals, pesticides, and contaminated sites. |
| EPCRA | Emergency Planning and Community Right-to-Know Act: A U.S. law requiring emergency planning and reporting on hazardous chemicals, releases, inventories, and toxic emissions. The information supports responders, regulators, and surrounding communities. |
| ERP | Emergency Response Plan: A detailed plan for organizing command, resources, communications, protective actions, medical support, containment, and recovery during emergencies requiring active response. |
| ERT | Emergency Response Team: Trained personnel assigned to respond to incidents such as fires, spills, rescues, medical emergencies, and hazardous-material releases within defined capability limits. |
| ESA | Environmental Site Assessment: A structured evaluation of environmental conditions and potential liabilities associated with real property. Phase I work emphasizes records, interviews, site observations, and recognized environmental conditions rather than intrusive sampling. |
| ETA | Event Tree Analysis: A forward-looking risk technique that maps possible outcomes after an initiating event based on the success or failure of safeguards and response functions. |
| EU-OSHA | European Agency for Safety and Health at Work: A European Union agency that provides research, guidance, tools, and campaign resources to support safer and healthier workplaces. |
| F | |
| FIFRA | Federal Insecticide, Fungicide, and Rodenticide Act: The U.S. law governing pesticide registration, labeling, distribution, sale, and use. Facilities using pesticides must follow label directions and applicable worker-protection requirements. |
| FMEA | Failure Modes and Effects Analysis: A systematic method for identifying how equipment, processes, or controls could fail, evaluating the consequences, and prioritizing preventive or mitigating action. |
| FRP | Facility Response Plan: A U.S. oil-spill response plan required for certain facilities that could cause substantial harm to navigable waters or adjoining shorelines. It addresses scenarios, resources, notifications, and response organization. |
| FTA | Fault Tree Analysis: A deductive method that starts with an undesired event and maps combinations of equipment failures, human errors, and conditions that could cause it. |
| G | |
| GFCI | Ground-Fault Circuit Interrupter: A protective device that rapidly disconnects power when it detects current leakage to ground. It reduces electric-shock risk in wet, temporary, construction, and other specified locations. |
| GHG | Greenhouse Gas: A gas that traps heat in the atmosphere, including carbon dioxide, methane, nitrous oxide, and fluorinated gases. Inventories support regulatory reporting, target setting, and emissions-reduction planning. |
| GHS | Globally Harmonized System of Classification and Labelling of Chemicals: A United Nations framework aligning chemical hazard classification, labels, pictograms, signal words, and safety data. Countries implement it through their own laws and regulations. |
| GWP | Global Warming Potential: A factor comparing the heat-trapping effect of a greenhouse gas with carbon dioxide over a specified time horizon. It is used to convert different gases into a common emissions unit. |
| H | |
| HAP | Hazardous Air Pollutant: A pollutant listed under the U.S. Clean Air Act because it may cause cancer, other serious health effects, or adverse environmental impacts. Covered sources may face technology-based and risk-based controls. |
| HAVS | Hand-Arm Vibration Syndrome: A potentially disabling condition involving vascular, neurological, and musculoskeletal damage from repeated exposure to vibrating tools. Prevention relies on exposure reduction, tool selection, maintenance, training, and health surveillance. |
| HAZCOM | Hazard Communication Standard: The U.S. workplace chemical-information rule requiring classification, labels, safety data sheets, written programs, and employee training for hazardous chemicals. |
| HAZID | Hazard Identification: A structured, often workshop-based process for identifying hazards and major accident scenarios early in a project or operational review. Results guide further analysis and design decisions. |
| HAZMAT | Hazardous Materials: Substances capable of creating health, safety, property, or environmental risks during use, storage, or transportation. Classification determines controls, packaging, documentation, and response requirements. |
| HAZOP | Hazard and Operability Study: A multidisciplinary, guideword-based review used to identify process deviations, causes, consequences, existing safeguards, and recommended actions. |
| HAZWOPER | Hazardous Waste Operations and Emergency Response: A U.S. workplace standard covering hazardous-waste site operations, certain treatment and disposal facilities, and emergency response to hazardous-substance releases. It establishes training, medical, planning, and control requirements. |
| HEPA | High-Efficiency Particulate Air: A filtration classification associated with removal of at least 99.97 percent of particles at the specified test size. Such filters are widely used for asbestos, lead, biological, and fine-particulate controls. |
| HHE | Health Hazard Evaluation: An investigation of potential workplace health hazards, including exposures, symptoms, work practices, and controls. In the United States, employers, employees, or representatives may request this service from the national occupational research agency. |
| HIRARC | Hazard Identification, Risk Assessment, and Risk Control: A structured process for identifying hazards, evaluating risk, selecting controls according to the hierarchy, and monitoring their effectiveness. |
| HMIS | Hazardous Materials Identification System: A workplace chemical-labeling system using color-coded ratings for health, flammability, and physical hazards, along with personal-protection information. It supplements rather than replaces required hazard communication. |
| HOP | Human and Organizational Performance: An operating philosophy that treats error as a normal feature of work and emphasizes system conditions, learning, capacity, and resilient defenses rather than blame alone. |
| HRA | Health Risk Assessment: A structured evaluation of potential adverse health effects from chemical, physical, or biological exposures. It integrates hazard, dose-response, exposure, and risk characterization. |
| HRA | Human Reliability Analysis: A process-safety method for estimating how human actions or errors may affect system performance and accident scenarios. It supports realistic treatment of operator response in quantitative risk work. |
| HREC | Historical Recognized Environmental Condition: A past release that has been addressed to unrestricted-use criteria without required controls. It is documented in a Phase I property assessment but is not treated as a current recognized condition. |
| HSE | Health, Safety, and Environment: An alternative ordering of the functions responsible for occupational health, workplace safety, environmental compliance, and operational risk management. |
| HSE | Health and Safety Executive: The United Kingdom regulator responsible for enforcing workplace health and safety law and publishing extensive technical guidance. |
| I | |
| I2P2 | Injury and Illness Prevention Program: A systematic program for identifying and correcting workplace hazards, engaging employees, investigating incidents, training personnel, and evaluating effectiveness. |
| IARC | International Agency for Research on Cancer: A World Health Organization agency that evaluates evidence on whether agents and exposures can cause cancer. Its hazard classifications are frequently used in occupational and environmental risk reviews. |
| IATA | International Air Transport Association: A global airline trade association whose dangerous-goods regulations provide widely used requirements for classifying, packaging, marking, labeling, documenting, and handling hazardous shipments by air. |
| ICS | Incident Command System: A standardized structure for command, control, coordination, communications, and resource management during emergencies. It allows organizations and public responders to work within a common framework. |
| IDLH | Immediately Dangerous to Life or Health: An atmospheric concentration that could cause death, irreversible harm, or impaired escape. Entry requires highly protective respiratory equipment and stringent emergency provisions. |
| IH | Industrial Hygiene: The discipline of anticipating, recognizing, evaluating, and controlling workplace factors that may cause illness, injury, impairment, or significant discomfort. |
| IIPP | Injury and Illness Prevention Program: A written workplace safety framework required in California and used elsewhere to assign responsibility, communicate hazards, conduct inspections, investigate incidents, correct deficiencies, and train employees. |
| ILO | International Labour Organization: A United Nations agency that establishes international labor standards and publishes conventions, guidance, and data on occupational safety and health. |
| IMDG | International Maritime Dangerous Goods Code: The international code governing dangerous-goods transport by sea. It addresses classification, packaging, marking, documentation, stowage, segregation, and emergency information. |
| IMS | Integrated Management System: A unified framework combining compatible environmental, occupational health and safety, quality, or other management-system requirements to reduce duplication and align governance. |
| IOSH | Institution of Occupational Safety and Health: A global professional body providing membership, qualifications, training, and guidance for occupational safety and health practitioners. |
| IPL | Independent Protection Layer: A safeguard that is independent of an initiating event and other credited safeguards, and that can prevent or mitigate a hazardous scenario with defined reliability. |
| ISO 14001 | International Organization for Standardization 14001 — Environmental Management Systems — Requirements with Guidance for Use: The internationally recognized certifiable standard for establishing, operating, auditing, and continually improving an environmental management system. |
| ISO 19011 | International Organization for Standardization 19011 — Guidelines for Auditing Management Systems: Guidance on audit principles, audit-program management, audit execution, and auditor competence for management-system assessments. |
| ISO 45001 | International Organization for Standardization 45001 — Occupational Health and Safety Management Systems — Requirements with Guidance for Use: The internationally recognized certifiable standard for managing occupational risks, worker participation, compliance obligations, objectives, and continual improvement. |
| J | |
| JHA | Job Hazard Analysis: A task-level method that breaks work into steps, identifies hazards at each step, and specifies controls before the work begins. |
| JSA | Job Safety Analysis: A pre-work review of task steps, hazards, and precautions. The term is often used interchangeably with job hazard analysis, although organizational formats may differ. |
| L | |
| LBP | Lead-Based Paint: Paint or another surface coating containing lead at or above an applicable regulatory threshold. Surveys and controls are important during renovation, demolition, maintenance, and housing-related work. |
| LCA | Life Cycle Assessment: A method for evaluating environmental inputs, outputs, and impacts across a product or service life cycle, from raw-material extraction through production, use, and end of life. |
| LDAR | Leak Detection and Repair: A program for monitoring regulated equipment components for fugitive emissions and repairing identified leaks within specified timeframes. It is a central air-compliance control in many process industries. |
| LDR | Land Disposal Restrictions: U.S. hazardous-waste requirements that generally prohibit land disposal unless waste meets treatment standards or qualifies for an exception. Compliance affects characterization, treatment, documentation, and disposal decisions. |
| LEL | Lower Explosive Limit: The lowest concentration of a gas or vapor in air that can propagate flame under specified conditions. Gas readings expressed as a percentage of this limit guide entry, hot-work, and emergency decisions. |
| LEPC | Local Emergency Planning Committee: A U.S. community body that develops hazardous-material emergency plans and receives chemical inventory and release information from covered facilities. |
| LEV | Local Exhaust Ventilation: An engineering control that captures airborne contaminants near their source and transports them through ductwork to treatment or safe discharge. |
| LI | Lifting Index: An ergonomics value comparing the load being lifted with a recommended weight under the task’s conditions. Values above one indicate increasing concern and a need to redesign or further evaluate the lift. |
| LNAPL | Light Non-Aqueous Phase Liquid: A liquid contaminant that does not readily mix with water and is less dense than water, causing it to accumulate near the water table. Petroleum fuels are common examples. |
| LOPA | Layer of Protection Analysis: A semi-quantitative process-risk method that compares scenario frequency and consequence with the risk reduction provided by independent protection layers. |
| LOPC | Loss of Primary Containment: An unplanned release of material or energy from equipment intended to contain it. Tracking these events helps identify process-safety weaknesses before they escalate into major incidents. |
| LOTO | Lockout/Tagout: A hazardous-energy control process that isolates equipment, applies locks and tags, dissipates stored energy, and verifies a zero-energy state before servicing or maintenance. |
| LQG | Large Quantity Generator: A U.S. hazardous-waste generator category based on monthly generation of regulated waste. It carries stringent accumulation, preparedness, training, manifesting, and reporting obligations. |
| LTI | Lost Time Injury: A work-related injury or illness resulting in time away from work beyond the organization’s defined threshold. Definitions should be standardized before comparing performance. |
| LTIFR | Lost Time Injury Frequency Rate: The number of lost-time cases normalized by hours worked. The multiplier differs across regions, so reporting must specify the calculation basis. |
| LTIR | Lost Time Incident Rate: A normalized lagging indicator of incidents resulting in lost work time. It is useful for trend analysis but should be paired with leading and severity measures. |
| M | |
| MACT | Maximum Achievable Control Technology: U.S. technology-based standards controlling hazardous air pollutants from major and certain area sources. Requirements are generally based on the emissions performance of the best-controlled similar sources. |
| MEC | Minimum Explosible Concentration: The lowest concentration of combustible dust dispersed in air that can support an explosion under specified test conditions. It informs dust hazard evaluation and housekeeping controls. |
| MEWP | Mobile Elevating Work Platform: Equipment that raises personnel to an elevated work position, including boom and scissor lifts. Risk controls include planning, operator qualification, inspection, stabilization, fall protection, and rescue. |
| MIE | Minimum Ignition Energy: The smallest spark energy capable of igniting a particular combustible mixture under specified test conditions. It helps determine sensitivity to static electricity and other ignition sources. |
| MIT | Minimum Ignition Temperature: The lowest temperature at which a combustible gas, vapor, dust cloud, or dust layer ignites under defined test conditions. Values support equipment and surface-temperature controls. |
| MNA | Monitored Natural Attenuation: A remediation approach that relies on verified natural physical, chemical, and biological processes to reduce contaminant mass, toxicity, mobility, or concentration while conditions are monitored. |
| MOC | Management of Change: A formal process for evaluating and authorizing changes to equipment, chemicals, technology, procedures, organization, or facilities before implementation. It helps prevent new hazards and unintended consequences. |
| MS4 | Municipal Separate Storm Sewer System: A publicly owned stormwater conveyance system that is separate from sanitary sewers. Regulated operators must implement programs to reduce pollutant discharges to receiving waters. |
| MSD | Musculoskeletal Disorder: An injury or disorder affecting muscles, tendons, ligaments, nerves, joints, cartilage, or spinal discs. Ergonomic assessment targets force, repetition, posture, vibration, and duration as contributing factors. |
| MSDS | Material Safety Data Sheet: The former name for a chemical hazard-information document in the United States. Legacy records remain common, but current hazard communication uses a standardized safety data sheet format. |
| MUC | Maximum Use Concentration: The highest atmospheric concentration in which a respirator may be used, based on its assigned protection factor, the exposure limit, and any lower manufacturer or regulatory restriction. |
| N | |
| NAAQS | National Ambient Air Quality Standards: U.S. health- and welfare-based limits for designated common air pollutants. An area’s attainment status influences permitting, planning, and emissions-control requirements. |
| NEBOSH | National Examination Board in Occupational Safety and Health: A United Kingdom-based awarding organization whose qualifications are widely used for safety, health, environmental, fire, and process-safety competence. |
| NEPA | National Environmental Policy Act: A U.S. law requiring federal agencies to assess environmental consequences before making certain major decisions. Reviews may include categorical exclusions, environmental assessments, or environmental impact statements. |
| NFPA | National Fire Protection Association: A nonprofit standards organization that develops widely adopted codes and standards addressing fire, electrical, combustible-dust, hazardous-material, and life-safety risks. |
| NIMS | National Incident Management System: The U.S. national framework for coordinating government, private-sector, and nonprofit emergency management. It standardizes terminology, command structures, resource management, and communications. |
| NIOSH | National Institute for Occupational Safety and Health: The U.S. federal research agency focused on preventing work-related injury and illness. It develops exposure recommendations, methods, guidance, and respirator approvals. |
| NOx | Nitrogen Oxides: A group of combustion-related air pollutants, principally nitric oxide and nitrogen dioxide. They contribute to ozone, particulate pollution, acid deposition, and permitting obligations. |
| NORM | Naturally Occurring Radioactive Material: Radioactive material present naturally in the environment that may become concentrated through industrial activity. Management can require surveys, exposure controls, licensing, transport, and specialized disposal. |
| NPDES | National Pollutant Discharge Elimination System: The U.S. permit program controlling point-source discharges to waters, including industrial wastewater, municipal effluent, stormwater, and certain construction activities. |
| NRC | United States Nuclear Regulatory Commission: The federal agency regulating commercial nuclear materials and facilities. Its requirements affect licensing, radiation protection, security, incident reporting, and decommissioning. |
| NRR | Noise Reduction Rating: A laboratory-derived rating shown on hearing protectors sold in the United States. Field attenuation is often lower, so hearing-protection assessments apply appropriate derating or fit-testing methods. |
| NSPS | New Source Performance Standards: U.S. air-emission standards for specified categories of new, modified, or reconstructed stationary sources. Requirements may include limits, work practices, monitoring, testing, and reporting. |
| NSR | New Source Review: A U.S. preconstruction air-permitting program for new and modified stationary sources. Applicability depends on location, emissions increases, source status, and pollutant-specific thresholds. |
| O | |
| OEL | Occupational Exposure Limit: A general term for a regulatory or advisory concentration limit intended to protect workers from harmful exposure to airborne contaminants. |
| OHS | Occupational Health and Safety: The discipline focused on preventing work-related injuries and illnesses through hazard control, worker participation, legal compliance, and systematic performance management. |
| OHSAS 18001 | Occupational Health and Safety Assessment Series 18001: A withdrawn occupational health and safety management-system specification formerly used for certification. Organizations generally transitioned to the current international management-system standard. |
| OHST | Occupational Hygiene and Safety Technician: A Board of Certified Safety Professionals credential for practitioners who perform occupational health and safety activities under established programs and procedures. |
| OSHA | Occupational Safety and Health Administration: The U.S. federal agency that sets and enforces workplace safety and health standards and provides compliance assistance, outreach, education, and training. |
| P | |
| P&ID | Piping and Instrumentation Diagram: A detailed process drawing showing piping, vessels, instruments, control loops, valves, and safeguards. Accurate drawings are foundational to process hazard reviews, isolation planning, and change control. |
| PACM | Presumed Asbestos-Containing Material: Certain thermal insulation, surfacing, or flooring materials that must be treated as asbestos-containing unless analysis demonstrates otherwise. The presumption triggers protective work practices and assessment obligations. |
| PAPR | Powered Air-Purifying Respirator: A battery-powered respirator that draws ambient air through filters or cartridges and supplies it to a facepiece, hood, or helmet. Selection depends on the hazard, protection factor, and approved configuration. |
| PBT | Persistent, Bioaccumulative, and Toxic: A classification for substances that resist degradation, build up in organisms, and cause toxic effects. These properties can drive restrictions, substitution, release prevention, and long-term environmental management. |
| PCB | Polychlorinated Biphenyl: A class of persistent toxic chemicals historically used in electrical equipment, sealants, and other materials. Management may involve inventory, marking, storage, cleanup, transport, and disposal requirements. |
| PCBU | Person Conducting a Business or Undertaking: A principal duty-holder under Australian and New Zealand work health and safety laws. The term can cover companies, partnerships, sole traders, government bodies, and other operating entities. |
| PDCA | Plan-Do-Check-Act: A continual-improvement cycle used to establish objectives and controls, implement them, evaluate results, and take corrective or improvement action. |
| PEL | Permissible Exposure Limit: A legally enforceable U.S. workplace exposure limit for a substance or physical agent. Limits may be expressed as full-shift averages, short-term limits, or ceilings. |
| PFAS | Per- and Polyfluoroalkyl Substances: A large family of persistent fluorinated chemicals used in many industrial and consumer applications. Evolving requirements affect inventories, drinking water, emissions, firefighting foam, waste, remediation, and liability assessment. |
| PFAS | Personal Fall Arrest System: An assembly used to stop a worker during a fall, typically comprising an anchorage, connector, and full-body harness. Design must control free-fall distance, clearance, arrest force, swing hazards, and rescue needs. |
| PFD | Process Flow Diagram: A high-level drawing showing major process equipment, principal flow paths, and key operating information. It supports process understanding and early hazard reviews. |
| PFT | Pulmonary Function Test: A test measuring lung volumes and airflow. Occupational programs use it for medical surveillance, respirator evaluations, and assessment of possible work-related respiratory impairment. |
| PHA | Process Hazard Analysis: A systematic review of process hazards, causes, consequences, safeguards, and recommendations using an appropriate methodology. It is a core requirement of major-hazard management programs. |
| PIT | Powered Industrial Truck: A mobile, power-propelled vehicle used to carry, push, pull, stack, or tier materials. Controls include operator training, inspections, pedestrian separation, load stability, and safe charging or fueling. |
| PM2.5 | Particulate Matter with a Diameter of 2.5 Micrometers or Less: Fine airborne particles capable of penetrating deep into the lungs and affecting cardiovascular and respiratory health. They are important in ambient-air compliance, wildfire response, and exposure assessment. |
| POTW | Publicly Owned Treatment Works: A publicly owned system that collects and treats municipal wastewater. Industrial users may be subject to pretreatment limits, permits, sampling, reporting, and discharge prohibitions. |
| PPE | Personal Protective Equipment: Wearable equipment used to reduce exposure to hazards when elimination, substitution, and engineering controls do not fully control risk. Selection requires hazard assessment, fit, training, inspection, and maintenance. |
| ppm | Parts per Million: A concentration unit commonly used for gases, vapors, water contaminants, and chemical mixtures. The measurement basis must be clear because volume, mass, and molar interpretations can differ. |
| PRCS | Permit-Required Confined Space: A confined space containing or potentially containing a hazardous atmosphere, engulfment hazard, entrapment configuration, or other serious hazard. Entry requires a formal permit system and defined protective measures. |
| PSD | Prevention of Significant Deterioration: A U.S. preconstruction air-permitting program for major sources in areas meeting applicable air-quality standards. It can require air-quality analysis and best available control technology. |
| PSE | Process Safety Event: An unplanned loss of primary containment that meets defined material, consequence, or release criteria. Tiered event tracking is used to compare major-hazard performance and identify systemic weaknesses. |
| PSIF | Potential Serious Injury or Fatality: An event or exposure that could reasonably have produced a life-altering injury or death even if the actual outcome was less severe. Reviewing this potential helps prioritize high-consequence risk controls. |
| PSM | Process Safety Management: A systematic approach to preventing catastrophic releases of highly hazardous chemicals through process information, hazard analysis, operating procedures, training, mechanical integrity, change control, and other elements. |
| PSSR | Pre-Startup Safety Review: A formal verification that construction, equipment, procedures, training, hazard-review actions, and readiness requirements are complete before introducing hazardous materials or starting a changed process. |
| PTW | Permit to Work: A documented authorization process for controlling high-risk, nonroutine work such as hot work, confined-space entry, excavation, line breaking, and electrical isolation. |
| Q | |
| QEP | Qualified Environmental Professional: A multidisciplinary credential demonstrating knowledge and experience across environmental science, regulation, assessment, and management. |
| QLFT | Qualitative Fit Test: A pass-or-fail respirator fit test based on whether the wearer detects a test agent. It is permitted only for specified respirator types and protection levels. |
| QNFT | Quantitative Fit Test: An instrumented respirator fit test that numerically measures leakage into the facepiece. The resulting fit factor verifies whether an individual achieves the required seal. |
| QRA | Quantitative Risk Assessment: A numerical evaluation of accident frequencies and consequences used to estimate individual, societal, environmental, or asset risk and compare results with defined criteria. |
| R | |
| RAGAGEP | Recognized and Generally Accepted Good Engineering Practices: Engineering codes, standards, technical practices, and internal specifications used as the basis for process-equipment design, inspection, testing, and maintenance under U.S. process-safety requirements. |
| RAMS | Risk Assessments and Method Statements: Documents commonly used in United Kingdom construction and contracting to explain task hazards, control measures, responsibilities, and the planned safe method of work. |
| RCA | Root Cause Analysis: A structured investigation method used to identify underlying technical, organizational, and human-system causes rather than stopping at immediate errors or conditions. |
| RCD | Residual Current Device: An electrical protective device that disconnects a circuit when it detects current leaking from the intended path. It is widely used internationally to reduce electric-shock risk. |
| RCRA | Resource Conservation and Recovery Act: The U.S. federal law governing hazardous and nonhazardous solid waste from generation through treatment, storage, and disposal. It also regulates underground storage tanks. |
| REBA | Rapid Entire Body Assessment: An observational ergonomics method that scores whole-body postures, force, repetition, coupling, and activity to prioritize tasks for redesign. |
| REC | Recognized Environmental Condition: The presence or likely presence of hazardous substances or petroleum products at a property due to a release, likely release, or material threat of release. It is a principal conclusion of Phase I property assessments. |
| REL | Recommended Exposure Limit: A science-based occupational exposure recommendation issued by the U.S. national occupational research agency. It is advisory unless adopted through another enforceable mechanism. |
| RIDDOR | Reporting of Injuries, Diseases and Dangerous Occurrences Regulations: United Kingdom regulations requiring responsible persons to report specified work-related deaths, injuries, diseases, and dangerous occurrences to the enforcing authority. |
| RIR | Recordable Incident Rate: The number of recordable work-related injury and illness cases normalized by hours worked. It is a lagging indicator used for trend and peer comparison. |
| RMP | Risk Management Plan: A U.S. regulatory program for facilities holding threshold quantities of specified hazardous substances. Covered sites analyze release scenarios and document prevention, emergency-response, and management measures. |
| ROPS | Rollover Protective Structure: A protective frame or cab designed to preserve a survival zone if mobile equipment overturns. Its effectiveness generally depends on proper use of the operator restraint system. |
| RPE | Respiratory Protective Equipment: The term commonly used outside the United States for respirators and associated equipment. Effective programs require suitable selection, fit, training, maintenance, and consideration of task and wearer factors. |
| RPN | Risk Priority Number: A score traditionally calculated from severity, occurrence, and detectability ratings in failure-mode analysis. It helps prioritize review, although the underlying ratings and high-severity issues should also be considered separately. |
| RSO | Radiation Safety Officer: The individual designated to oversee a licensed or registered radiation-protection program, including training, surveys, dosimetry, records, security, and regulatory reporting. |
| RULA | Rapid Upper Limb Assessment: An observational ergonomics method for evaluating neck, trunk, and upper-limb postures, muscle use, and force during work tasks. |
| RWL | Recommended Weight Limit: The load weight considered acceptable for a specified two-handed lifting task under the revised national lifting equation. It is calculated from task geometry, frequency, duration, asymmetry, and hand coupling. |
| S | |
| SARA | Superfund Amendments and Reauthorization Act: A 1986 U.S. law that amended federal contaminated-site requirements and created major emergency-planning and community chemical-information obligations under Title III. |
| SCBA | Self-Contained Breathing Apparatus: A respirator that supplies breathing air from a cylinder carried by the user. Positive-pressure units are used for oxygen-deficient, unknown, or immediately dangerous atmospheres and emergency response. |
| SCE | Safety-Critical Element: Equipment, systems, or structures whose failure could cause or contribute substantially to a major accident, or whose purpose is to prevent or limit one. Performance standards define required functionality, availability, reliability, and survivability. |
| SDS | Safety Data Sheet: A standardized 16-section document describing a chemical’s hazards, composition, protective measures, emergency actions, handling, storage, and regulatory information. |
| SIF | Safety Instrumented Function: An automated protective action implemented by sensors, logic solving, and final elements to move a process to a safe state when specified conditions occur. |
| SIF | Serious Injury and Fatality: A classification focused on life-threatening, life-altering, and fatal outcomes. Programs using this lens prioritize high-energy hazards and critical controls rather than relying only on total injury counts. |
| SIL | Safety Integrity Level: A discrete level specifying the required risk-reduction performance of a safety instrumented function. Higher levels require lower probability of dangerous failure and greater lifecycle rigor. |
| SIS | Safety Instrumented System: The sensors, logic solvers, final control elements, and supporting components used to perform one or more automated protective functions in a process. |
| SMS | Safety Management System: A formal framework for governing safety policy, accountability, risk management, assurance, communication, competence, and continual improvement. |
| SOP | Standard Operating Procedure: A controlled document specifying the approved steps, responsibilities, precautions, limits, and records for performing a recurring activity safely and consistently. |
| SOx | Sulfur Oxides: Air pollutants produced mainly by combustion or processing of sulfur-containing materials. They contribute to respiratory effects, particulate formation, acid deposition, and air-permit obligations. |
| SPCC | Spill Prevention, Control, and Countermeasure: A U.S. program requiring certain facilities with oil storage to prepare and implement plans preventing discharges to navigable waters and adjoining shorelines. |
| SQG | Small Quantity Generator: A U.S. hazardous-waste generator category based on monthly generation. Applicable requirements cover accumulation limits, storage time, labeling, emergency arrangements, manifests, and employee familiarity. |
| SRL | Self-Retracting Lifeline: A fall-protection connector that extends and retracts with worker movement and locks rapidly during a fall. Selection must account for anchorage location, clearance, edge exposure, compatibility, and rescue. |
| STEL | Short-Term Exposure Limit: The maximum allowable or recommended average exposure over a short period, commonly 15 minutes. It controls brief peaks that a full-shift average might obscure. |
| STS | Standard Threshold Shift: A defined worsening in an employee’s hearing thresholds compared with baseline. It triggers follow-up actions within occupational hearing-conservation programs. |
| SWMS | Safe Work Method Statement: An Australian document required for high-risk construction work that identifies the activity’s hazards, controls, implementation arrangements, and monitoring responsibilities. |
| SWPPP | Stormwater Pollution Prevention Plan: A site-specific plan describing potential pollutant sources, drainage, inspections, controls, monitoring, corrective actions, and records required under a stormwater permit. |
| T | |
| TCIR | Total Case Incident Rate: A lagging indicator that normalizes recordable injury and illness cases, commonly per 200,000 hours worked. It supports internal trending and external benchmarking when definitions are consistent. |
| TCLP | Toxicity Characteristic Leaching Procedure: A U.S. laboratory method used to estimate how specified contaminants may leach from waste. Results help determine whether a waste exhibits the toxicity characteristic for hazardous-waste regulation. |
| TLV | Threshold Limit Value: A health-based occupational exposure guideline published by the American Conference of Governmental Industrial Hygienists. It is not inherently enforceable unless adopted by an authority or organization. |
| TRI | Toxics Release Inventory: A U.S. public reporting program requiring covered facilities to report quantities of listed chemicals released, treated, recycled, combusted for energy recovery, or transferred off-site. |
| TRIR | Total Recordable Incident Rate: The number of recordable work-related injuries and illnesses normalized to a standard workforce exposure basis. It is widely used but should not be the sole measure of safety performance. |
| TSCA | Toxic Substances Control Act: The U.S. law authorizing federal oversight of industrial chemicals, including reporting, evaluation, restrictions, testing, recordkeeping, and management of specified substances. |
| TSDF | Treatment, Storage, and Disposal Facility: A facility that treats, stores, or disposes of regulated hazardous waste and generally operates under detailed permitting, technical, financial-assurance, and recordkeeping requirements. |
| TSS | Total Suspended Solids: The mass of suspended particles in water or wastewater. It is a common permit parameter and indicator of treatment, erosion, sediment, and stormwater-control performance. |
| TWA | Time-Weighted Average: An average exposure calculated over a defined period, commonly an eight-hour work shift. It accounts for changing concentrations throughout the sampling period. |
| U | |
| UEL | Upper Explosive Limit: The highest concentration of a gas or vapor in air that can propagate flame under specified conditions. Above this concentration the mixture is too fuel-rich to burn, but dilution can move it into the explosive range. |
| UIC | Underground Injection Control: A U.S. regulatory program protecting underground sources of drinking water from injection-well activities. Requirements vary by well class, fluid, construction, operation, monitoring, and closure conditions. |
| USCG | United States Coast Guard: The federal service with significant responsibilities for maritime safety, hazardous-material transport, waterfront facilities, oil-spill preparedness, and marine environmental response. |
| UST | Underground Storage Tank: A tank and connected piping meeting regulatory criteria for underground installation. Compliance commonly addresses release detection, corrosion protection, spill and overfill controls, financial responsibility, and closure. |
| V | |
| VCE | Vapor Cloud Explosion: An explosion following ignition of a dispersed cloud of flammable vapor. Congestion, confinement, fuel properties, weather, and ignition timing strongly influence consequences. |
| VOC | Volatile Organic Compound: An organic chemical that readily enters the atmosphere and may contribute to ozone formation, worker exposure, odor, or toxic effects. Regulatory definitions and exemptions vary by jurisdiction. |
| VPP | Voluntary Protection Programs: A U.S. recognition program for employers and workers with comprehensive safety and health management systems and performance exceeding basic compliance expectations. |
| VSQG | Very Small Quantity Generator: The smallest U.S. hazardous-waste generator category, subject to reduced but still important identification, accumulation, delivery, and acute-waste requirements. |
| W | |
| WBGT | Wet Bulb Globe Temperature: A heat-stress index incorporating temperature, humidity, radiant heat, and air movement. It supports work-rest schedules, acclimatization, hydration, and clothing-adjustment decisions. |
| WEEL | Workplace Environmental Exposure Level: A health-based occupational exposure guideline developed for substances lacking other authoritative limits. It supports risk assessment and control decisions when regulatory values are unavailable. |
| WHMIS | Workplace Hazardous Materials Information System: Canada’s national workplace chemical-hazard communication framework. It establishes duties for classification, labels, safety data sheets, worker education, and training. |
| WHS | Work Health and Safety: The terminology and legal framework used in Australia and several neighboring jurisdictions for duties relating to worker health, safety, consultation, risk management, and incident notification. |
| WMSD | Work-Related Musculoskeletal Disorder: A musculoskeletal condition caused or aggravated by work factors such as force, repetition, awkward posture, contact stress, vibration, or insufficient recovery. |
| X | |
| XRF | X-Ray Fluorescence: A nondestructive analytical technique that identifies and quantifies elements in materials. Portable instruments are frequently used to screen painted surfaces, soil, dust, alloys, and consumer materials for metals such as lead. |