Your FREE ASP Flashcards 2026 – 150+ Cards

Recordable injuries and illnesses per 100 full-time workers: (recordable cases × 200,000) ÷ total hours worked. The 200,000 base equals 100 workers × 2,000 hours/year.

Days Away, Restricted, or Transferred rate: (DART cases × 200,000) ÷ total hours worked. Counts only cases serious enough to cause time away, restriction, or job transfer.

Lost workdays per 100 workers: (total lost workdays × 200,000) ÷ total hours worked. Measures how many days injuries cost, not how often they occur.

Lost-time injuries per one million hours worked: (lost-time injuries × 1,000,000) ÷ total hours worked. Uses a 1,000,000-hour base, unlike OSHA's 200,000.

The standardizing factor in OSHA incidence rates, equal to 100 full-time workers each working 2,000 hours per year. It lets facilities of different sizes be compared on a per-100-worker basis.

Sum of (actual time ÷ permissible time) for each exposure level, × 100. A dose over 100% exceeds the OSHA permissible exposure limit (PEL).

OSHA halves the permissible exposure time for every 5-dB increase in sound level (90 dBA → 8 h, 95 dBA → 4 h, 100 dBA → 2 h). ACGIH/NIOSH use a 3-dB exchange rate.

TWA = 16.61 × log₁₀(D ÷ 100) + 90, where D is the percent dose. A 100% dose = 90 dBA TWA; a 200% dose = 95 dBA TWA.

Illuminance from a point source varies as 1 ÷ distance². Doubling the distance from a lamp reduces illuminance to one-quarter (e.g., 800 lux at 2 m → 200 lux at 4 m).

A logarithmic measure of hydrogen-ion concentration. Each one-unit drop in pH multiplies [H⁺] by 10; a drop from pH 7 to pH 5 increases [H⁺] 100-fold.

When two forces act at right angles, the resultant magnitude is the Pythagorean combination √(F₁² + F₂²). Two 50 N forces at 90° give about 70 N.

For resistors in parallel, 1/R(eq) = 1/R₁ + 1/R₂ + … The equivalent resistance is always less than the smallest resistor (6 Ω ∥ 3 Ω = 2 Ω).

The time for a quantity to decay to half its value. After n half-lives, a fraction (½)ⁿ remains (160 g after three 8-hour half-lives = 20 g).

Period T is the inverse of frequency f: T = 1 ÷ f. An oscillation at 2 Hz has a period of 0.5 seconds.

For a binomial distribution, variance = n × p × (1 − p), where n is the number of trials and p the probability of success.

For a constant contaminant generation rate, steady-state concentration is proportional to G ÷ Q (generation ÷ airflow). Doubling clean make-up airflow roughly halves the concentration.

In FMEA, RPN = Severity × Occurrence × Detection. Higher RPNs flag failure modes to address first.

The continuous-improvement cycle at the heart of a safety management system: Plan objectives and controls, Do/implement them, Check results against targets, Act to correct and improve.

A structured, organization-wide framework of policy, planning, implementation, evaluation, and continuous improvement for managing safety risk (e.g., ANSI/ASSP Z10, ISO 45001).

The international consensus standard for occupational health and safety management systems, built on the Plan-Do-Check-Act cycle and risk-based thinking.

The U.S. consensus standard for occupational health and safety management systems, emphasizing management leadership, employee participation, and continual improvement.

Controls ranked most to least effective: Elimination → Substitution → Engineering controls → Administrative controls → Personal protective equipment (PPE).

The most effective control: physically removing the hazard from the workplace entirely. It is preferred over all other levels of the hierarchy of controls.

Replacing a hazard with a less hazardous alternative (e.g., a water-based solvent for a flammable one). Second only to elimination in the hierarchy of controls.

Controls that isolate people from a hazard through design — machine guards, ventilation, enclosures, interlocks. They work without relying on worker behavior.

Controls that change how people work — procedures, training, job rotation, scheduling, signage. They depend on human behavior and so are weaker than engineering controls.

The last line of defense — gloves, respirators, hearing protection, fall harnesses. It does not remove the hazard and sits at the bottom of the hierarchy of controls.

Proactive, predictive safety metrics measured before incidents occur — inspections completed, near-misses reported, training delivered, observations performed.

Reactive safety metrics measured after incidents — TRIR, DART, fatalities, lost workdays. They show outcomes but not why they happened.

Also called a Job Hazard Analysis. A technique that breaks a task into steps, identifies the hazard of each step, and specifies controls to prevent harm.

A program that improves safety by observing, measuring, and reinforcing safe behaviors and reducing at-risk ones, using peer feedback and positive reinforcement.

The shared values, attitudes, and behaviors around safety in an organization — how people act when no one is watching. A strong culture treats safety as a core value, not a priority that can be displaced.

The systematic process of identifying hazards and evaluating the risk (severity × likelihood) they pose, so controls can be prioritized.

A grid that plots severity against probability to assign a risk level (e.g., low/medium/high), helping prioritize which hazards to control first.

H.W. Heinrich's model in which an injury is the last of five falling dominoes; removing the central domino — the unsafe act or unsafe condition — stops the sequence and prevents injury.

Heinrich's proposed ratio of 1 major injury : 29 minor injuries : 300 no-injury accidents (near misses), suggesting that reducing minor events reduces major ones.

A pyramid illustrating that for every serious injury there are many minor injuries and far more near misses — used to argue that near-miss reporting prevents future serious harm.

James Reason's model: accidents happen when holes in multiple layers of defense (each layer a slice of cheese) momentarily line up, letting a hazard pass through to cause harm.

An unsafe act is a behavior that departs from safe practice (bypassing a guard); an unsafe condition is a physical or environmental hazard (a frayed cord). Most incidents involve both.

A structured, retrospective investigation to find the underlying system causes of an incident — not just the immediate cause — so corrective actions prevent recurrence.

A root-cause technique that repeatedly asks 'why' to move from a symptom to the underlying system cause of an incident.

The fact-finding process after an incident or near miss to determine what happened and why, focused on fixing systems rather than assigning blame.

The right and responsibility of any worker to halt a task they believe is unsafe, without fear of reprisal, until the hazard is resolved.

The 29 CFR 1910.147 procedure that isolates and de-energizes hazardous energy during servicing, locks and tags the energy-isolating device, and verifies zero energy before work.

Attempting to operate the equipment after lockout to confirm it cannot start — the step that proves the machine is truly de-energized (zero-energy state) before maintenance begins.

A confined space (29 CFR 1910.146) with a hazardous atmosphere, engulfment risk, entrapment configuration, or other serious hazard, requiring a written permit and atmospheric testing before entry.

Test in sequence: oxygen first, then flammable gases and vapors, then toxic contaminants — because oxygen level affects the readings of the other instruments.

A standardized 16-section document (OSHA Hazard Communication Standard) giving the hazards, handling, exposure controls, and emergency measures for a chemical.

OSHA 29 CFR 1910.1200, aligned with the GHS, requiring labels, Safety Data Sheets, a written program, and worker training on hazardous chemicals.

A work-related case involving death, days away from work, restricted work or transfer, medical treatment beyond first aid, loss of consciousness, or a significant diagnosis.

First aid (e.g., a butterfly bandage, a tetanus shot, non-prescription medicine) does not make a case recordable; medical treatment beyond first aid does.

A systematic, documented evaluation of how well safety programs and management systems conform to requirements, identifying gaps for corrective action.

A compliance audit checks conformance to specific regulations or standards; a management-system audit evaluates whether the overall system is effective and improving.

An unplanned event that could have caused injury or damage but did not, by chance or timely intervention. Reporting near misses is a key proactive (leading) safety practice.

Designing out hazards in the earliest stages of a facility, process, or product, when changes are cheapest and most effective — an upstream application of the hierarchy of controls.

The science of fitting the task, tool, and workplace to the worker's capabilities to reduce fatigue, error, and musculoskeletal disorders.

A body position in which joints are naturally aligned and muscles and tendons are at their resting length, minimizing strain. Designing for neutral posture is a core ergonomic goal.

An injury or disorder of muscles, nerves, tendons, joints, or discs (e.g., carpal tunnel syndrome, tendinitis), often caused by repetition, force, awkward posture, or vibration.

Conditions that raise MSD risk: high force, repetition, awkward or static postures, contact stress, vibration, and cold. Risk grows when several combine.

A method that computes a Recommended Weight Limit (RWL) for two-handed lifting from a Load Constant (51 lb) multiplied by six task multipliers (horizontal, vertical, distance, asymmetry, frequency, coupling).

The maximum load a healthy worker can lift under given task conditions without elevated low-back risk: RWL = LC × HM × VM × DM × AM × FM × CM.

In the NIOSH Lifting Equation, the reference maximum load of 51 lb (23 kg) lifted under ideal conditions, before any task multipliers reduce it.

The actual load weight divided by the RWL. LI ≤ 1.0 means most healthy workers can lift safely; LI > 1.0 indicates increasing low-back injury risk and a need to redesign the task.

The NIOSH factor that penalizes loads held far from the body. Keeping the load close to the body raises HM and the RWL — the single biggest lever in most lifts.

Postural assessment tools: RULA (Rapid Upper Limb Assessment) scores upper-body strain; REBA (Rapid Entire Body Assessment) scores the whole body. Higher scores mean more urgent change.

The branch of ergonomics dealing with mental workload, attention, memory, and decision-making — designing displays, alarms, and tasks to reduce error.

The primary concern with vibrating power tools: prolonged vibration damages blood vessels and nerves in the hands (vibration white finger), causing numbness and reduced grip.

The study of human body measurements (reach, height, strength ranges) used to design workstations that accommodate the range of users, often the 5th to 95th percentile.

An ergonomic guideline: the top of the screen at or just below eye level, about an arm's length away, to keep the neck neutral and reduce eye and neck strain.

Ordinary combustibles — wood, paper, cloth, most plastics. Best extinguished by water or multipurpose dry chemical (cooling).

Flammable and combustible liquids and gases — gasoline, oil, solvents. Extinguished by smothering or interrupting the chemical reaction (foam, CO₂, dry chemical).

Fires involving energized electrical equipment. Use a non-conductive agent such as CO₂ or dry chemical; de-energizing reclassifies the fire to A or B.

Combustible metals — magnesium, titanium, sodium, lithium. Requires a special dry-powder agent; water can react violently.

Cooking oils and fats in commercial kitchens. Extinguished with a wet-chemical agent that saponifies the oil and cools it to prevent reignition.

The three elements needed for combustion: fuel, oxygen (oxidizer), and heat. Remove any one and the fire goes out.

Extends the fire triangle by adding a fourth element — the uninhibited chemical chain reaction. Agents like dry chemical and halon work by interrupting this reaction.

The lowest temperature at which a liquid gives off enough vapor to form an ignitable mixture near its surface (a momentary flash). A lower flash point means greater fire hazard.

The temperature, slightly above the flash point, at which a liquid produces enough vapor to sustain continuous burning rather than a momentary flash.

The lowest temperature at which a substance ignites spontaneously in air without an external spark or flame.

A liquid with a flash point below 100 °F (37.8 °C). Combustible liquids have flash points at or above 100 °F. Lower flash point = higher hazard.

The minimum vapor concentration in air that can propagate flame. Below the LEL the mixture is too lean (too little fuel) to ignite.

The maximum vapor concentration in air that can propagate flame. Above the UEL the mixture is too rich (too little oxygen) to ignite.

The near-simultaneous ignition of all combustible surfaces in a compartment when accumulated heat and gases reach ignition temperature — a sudden, deadly transition to a fully involved fire.

Dividing a building with fire-rated walls, floors, and doors to contain fire and smoke to the area of origin, limiting spread and protecting egress.

A rated assembly that resists fire spread; it must be self-closing and self-latching to perform — a fire door propped open provides no protection.

An automatic fire-suppression system; wet-pipe systems hold water in the piping for fast response, while individual heads open only over the fire (not all at once).

A gaseous, residue-free agent (e.g., FM-200, inert gas) used where water would damage equipment — ideal for data centers, control rooms, and archives.

The National Fire Protection Association, which publishes consensus fire-safety codes and standards (e.g., NFPA 30 flammable liquids, NFPA 70 electrical, NFPA 101 Life Safety Code).

Extinguishers must be placed so workers do not travel more than a set maximum distance to reach one (e.g., up to 75 ft for ordinary Class A hazards under OSHA 1910.157).

A standardized, scalable command structure for managing the command, control, and coordination of emergency response across agencies — a core component of NIMS.

FEMA's nationwide framework that enables agencies at all levels to work together using common terminology, structures (ICS), and processes during emergencies.

The single person with overall authority and responsibility for managing an incident, establishing objectives, and directing all response operations under ICS.

An ICS structure used when multiple agencies share jurisdiction over an incident, allowing them to set common objectives and strategies without surrendering their own authority.

The ICS principle that one supervisor should manage roughly three to seven subordinates (optimal of five) to keep an emergency response effective.

The section that collects and evaluates incident information and prepares the Incident Action Plan; the Operations Section carries it out.

Required by OSHA 29 CFR 1910.38, a written plan (oral allowed for ≤10 employees) covering evacuation procedures, alarm systems, emergency reporting, and employee accountability.

The ICS Command Staff member responsible for communicating accurate, timely information to the public and media during an incident.

A prearranged agreement between organizations or jurisdictions to share resources and assistance during emergencies that exceed one party's capacity.

The process of removing or neutralizing hazardous contaminants from people, equipment, and the environment to prevent the spread of harm during emergency response.

Hazardous Waste Operations and Emergency Response — OSHA 29 CFR 1910.120, governing cleanup operations, treatment/storage/disposal facilities, and emergency response to hazardous-substance releases.

The lowest HAZWOPER training tier (1910.120(q)): personnel who may witness or discover a release and are trained only to recognize it, notify authorities, and secure the area — not to act.

Three control zones around a release: the Exclusion (hot) zone of contamination, the Contamination Reduction (warm) zone for decon, and the Support (cold) zone that is clean.

A discussion-based drill in which response teams talk through their roles in a simulated emergency scenario, validating the plan without deploying resources.

A designated safe location to which evacuees report so the organization can account for all personnel after an evacuation.

A plan to keep critical operations running and recover quickly after a disruptive event, complementing the emergency response and evacuation plans.

The science of anticipating, recognizing, evaluating, and controlling workplace conditions (chemical, physical, biological, ergonomic) that may cause worker illness or injury.

OSHA's legally enforceable maximum exposure to a substance, usually an 8-hour time-weighted average, sometimes a ceiling or short-term limit.

ACGIH's recommended (not legally enforceable) airborne concentration to which nearly all workers may be repeatedly exposed day after day without adverse health effects.

The time-weighted-average TLV: the average airborne concentration for a normal 8-hour workday and 40-hour week.

Threshold Limit Value – Short-Term Exposure Limit: a 15-minute time-weighted average that should not be exceeded, even if the 8-hour TWA is within limits.

A concentration that must not be exceeded at any instant during the exposure — an absolute cap, unlike a TWA averaged over time.

An average exposure concentration over a defined period (usually 8 hours), weighting each level by the time spent at it.

An exposure threshold (often half the PEL) that triggers required activities — exposure monitoring, medical surveillance, or training — before the PEL is reached.

Sets a 90-dBA 8-hour PEL, a 5-dB exchange rate, and a hearing conservation program triggered at an 85-dBA action level (audiometric testing, training, hearing protection).

Measuring a worker's actual noise exposure over a shift with a body-worn dosimeter to compute the dose and TWA and compare against the PEL.

A heat-stress index combining dry-bulb, natural wet-bulb, and globe (radiant) temperatures into one value used to set work/rest schedules in hot environments.

A measure of a liquid's tendency to evaporate; higher vapor pressure means more vapor in the air and a greater inhalation exposure hazard.

When two substances together produce a combined health effect greater than the sum of their individual effects (2 + 2 = 5), increasing risk beyond either alone.

The pathways by which a contaminant enters the body: inhalation (most common at work), skin/eye absorption, ingestion, and injection.

Airborne particles of biological origin — bacteria, fungi/mold spores, viruses, pollen — that can cause infection, allergy, or respiratory illness.

An analytical method that separates and quantifies volatile chemical compounds in an air sample, widely used in industrial-hygiene laboratories.

Immediately Dangerous to Life or Health: an atmosphere posing an immediate threat to life, permanent health damage, or escape impairment, requiring the highest-level respiratory protection.

OSHA's standard requiring a written program, hazard assessment, medical evaluation, fit testing, and training before workers use respirators; fit testing is required at least annually.

Capturing a contaminant at its source (a hood near the process) before it spreads, the preferred engineering control over general dilution ventilation for toxic agents.

A systematic evaluation of the likely environmental effects of a proposed project before it proceeds, so impacts can be avoided, reduced, or mitigated.

The U.S. law governing hazardous and solid waste from generation to disposal, commonly described as 'cradle-to-grave' regulation administered by the EPA.

The principle that a hazardous waste is tracked and regulated through its entire life — generation, transport, treatment, storage, and disposal — central to RCRA.

Under 40 CFR Part 261, a solid waste is hazardous if it exhibits ignitability, corrosivity, reactivity, or toxicity (the four characteristics).

EPA classifies generators by monthly quantity: Very Small Quantity Generator (VSQG), Small Quantity Generator (SQG), and Large Quantity Generator (LQG), each with different requirements.

The shipping document that tracks hazardous waste from the generator through transporters to the permitted disposal facility, completing the cradle-to-grave chain.

A property whose redevelopment is complicated by the presence (or perceived presence) of a hazardous substance, pollutant, or contaminant.

A records, site, and interview review to identify potential or existing environmental contamination on a property — no sampling. Phase II adds sampling if Phase I finds concerns.

A 'cradle-to-grave' analysis of a product's environmental impacts across its entire life — raw materials, manufacture, use, and disposal.

The international standard for environmental management systems, built on the Plan-Do-Check-Act cycle, helping organizations manage and reduce environmental impacts.

U.S. federal laws administered by the EPA that regulate air emissions and discharges to surface waters, respectively, with permitting and reporting requirements.

Designing chemical products and processes to reduce or eliminate the use and generation of hazardous substances — preventing pollution at the source.

Development that meets present needs without compromising the ability of future generations to meet their own needs, balancing economic, social, and environmental goals.

Malcolm Knowles' principles: adults are self-directed, draw on experience, are problem-centered, and want relevant, immediately applicable training — so engage them actively, not by lecture alone.

A model for evaluating training: Level 1 Reaction (did they like it?), Level 2 Learning (did they learn?), Level 3 Behavior (do they apply it?), Level 4 Results (did it affect outcomes?).

The highest evaluation level, measuring the training's impact on organizational outcomes — for safety training, a measurable reduction in incident or injury rates.

A specific, measurable statement of what a learner will be able to do after training, written with an action verb (e.g., 'demonstrate' confined-space entry), guiding design and assessment.

The most effective method for teaching psychomotor skills (donning a respirator, using an extinguisher) because learners practice the actual task with feedback.

A short, informal, frequent safety meeting focused on one specific hazard or task, often delivered at the worksite before a shift — ideal for timely, job-specific reinforcement.

Under 1910.1200, workers must be trained on hazardous chemicals at their initial assignment and whenever a new chemical hazard is introduced into their work area.

Under 1910.1030, employees with occupational exposure must receive training at initial assignment and at least annually thereafter.

Documenting who was trained, on what, and when proves regulatory compliance, identifies refresher needs, and provides legal evidence of due diligence.

Graphics, diagrams, and danger/warning/caution signs reinforce safety messages quickly, overcome language and literacy barriers, and aid retention.

Built-in opportunities for learners to ask questions, practice, and be corrected, plus surveys and assessments that let trainers improve the program (a Level 1/2 evaluation input).

The up-front analysis of what knowledge or skill gaps exist and who needs training, so the program targets real performance needs rather than guesswork.

Designing training for diverse learners — multiple languages, reading levels, and accommodations for disabilities — so every worker can understand the safety message.

Section 5(a)(1) of the OSH Act: employers must furnish a workplace free from recognized hazards causing or likely to cause death or serious physical harm — used when no specific standard applies.

To cite under 5(a)(1), OSHA must show a hazard existed, it was recognized, it was causing or likely to cause death or serious harm, and a feasible means of abatement existed.

Capable of being done after considering cost, technology, and time — not merely technologically possible and not necessarily immediate.

The law that created OSHA, NIOSH, and the OSHRC, establishing the duty to provide safe and healthful working conditions for workers.

OSHA (Dept. of Labor) sets and enforces workplace safety regulations; NIOSH (CDC) is the research agency that recommends exposure limits and studies workplace hazards.

An OSHA violation committed with intentional disregard for, or plain indifference to, the law — the most serious category, carrying the highest penalties.

Failure to exercise the care that a reasonable person would in the circumstances, resulting in harm — a key concept in workplace-injury liability.

Liability for harm caused by a product or activity regardless of fault or intent — applied, for example, to defective products that injure users.

Taking all reasonable, demonstrable steps to identify and control hazards and comply with the law; documentation of these steps is a defense against liability.

A no-fault insurance system that pays medical costs and lost wages for work-related injuries in exchange for the employee generally giving up the right to sue the employer.

OSHA Section 11(c) prohibits employers from retaliating against workers who report safety violations or exercise their rights under the OSH Act.

Balancing duties to the public, employer, and profession; safety professionals must protect worker health even when it conflicts with cost or schedule pressures.

The level of caution and competence a reasonably prudent safety professional would exercise; falling below it can establish negligence.

A consensus standard (NFPA, ANSI, ASTM) is voluntary unless adopted by reference into a regulation; a regulation (OSHA, EPA) is legally enforceable.

A BCSP credential earned by passing the ASP exam, demonstrating foundational safety competency and serving as the stepping stone to the Certified Safety Professional (CSP).