NCSO cheat sheet

The PDCA cycle (Plan-Do-Check-Act) is the continuous improvement model underlying most OHS management systems, including ISO 45001.

Leading indicators (training completion, hazard reports, inspections) measure preventive effort; lagging indicators (injury rates, lost-time claims) measure outcomes.

DART rate = (number of days away, restricted, or transferred cases × 200,000) / total hours worked.

TRIR (Total Recordable Incident Rate) = (recordable cases × 200,000) / total hours worked; the 200,000 factor normalizes to 100 full-time workers at 2,000 hours/year.

A written OHS policy should state management commitment, worker participation, and the right to refuse unsafe work; it must be signed by the most senior executive.

Management review must occur at planned intervals (typically annually) and address audit results, incident trends, legal compliance, and resource needs.

Responsibility for OHS is shared: employers provide a safe workplace, supervisors ensure compliance, workers follow procedures and report hazards.

A safety management system typically includes: policy, organizing, planning and implementation, evaluation, and corrective action (the CSA Z45001/ISO 45001 structure).

Cost-benefit analysis of controls should account for direct costs (claims, fines) and indirect costs (lost productivity, training replacement workers), often estimated at 4–10× direct costs.

The hierarchy of legal authority: constitution → statutes/acts → regulations → standards incorporated by reference → guidance/policy.

Occupational health and safety acts impose a general duty on employers to take all reasonable precautions to protect workers; regulations provide specific requirements.

The Internal Responsibility System (IRS) assigns OHS duties to every workplace party-employer, supervisor, worker, and (where required) joint health and safety committee.

Workers have three core rights: the right to know about hazards, the right to participate in OHS, and the right to refuse unsafe work.

Joint Health and Safety Committees (JHSC) are required in most jurisdictions above a worker threshold (commonly 20 or 25 workers); certified worker members are often mandated.

Due diligence is a legal defense requiring the employer to show reasonable steps were taken to prevent the incident; documentation is essential evidence.

Standards such as CSA Z1000 (OHS management), CSA Z94.4 (respirator selection/use), and ACGIH TLVs provide technical benchmarks but are not law unless incorporated.

Penalties for OHS violations can include fines, imprisonment, and, in some jurisdictions, directors' personal liability; Bill C-45 (Westray) established criminal liability for organizations.

Regulations specify exposure limits, training requirements, recordkeeping periods, and reporting timelines for serious injuries and fatalities (often immediately or within 24 hours).

Risk = probability × severity; a risk matrix (e.g., 5×5) ranks hazards as low, medium, high, or critical to prioritize controls.

The hierarchy of controls, most to least effective: elimination, substitution, engineering controls, administrative controls, personal protective equipment (PPE).

Hazard identification methods include job hazard analysis (JHA), task-based risk assessment, inspections, incident reviews, and worker reports.

ALARP (As Low As Reasonably Practicable) is the principle that risk should be reduced until further reduction is grossly disproportionate to the benefit.

A hazard is a source of potential harm; risk is the combination of likelihood and consequence of that harm occurring.

Residual risk is the risk remaining after controls are applied; it must be documented and accepted by an authorized person.

Change management requires reassessing risk whenever processes, equipment, chemicals, or staffing change.

Bow-tie analysis links threats and consequences through preventive and mitigative barriers around a top event.

PPE is the last line of defense because it relies on correct selection, fit, training, and consistent use; it protects only the wearer.

Inspections are routine, focused checks of conditions and behaviors; audits are systematic, documented evaluations against a standard (e.g., ISO 45001, COR).

Incident investigation steps: secure the scene, provide care, gather evidence, interview witnesses, determine root causes, recommend corrective actions, and follow up.

Root cause analysis tools include 5 Whys, fishbone (Ishikawa) diagrams, fault tree analysis, and events and causal factors (ECF) charts.

The domino theory (Heinrich) and the Swiss cheese model (Reason) explain how multiple failures align to cause incidents; latent conditions often underlie active failures.

Near-miss reporting should be encouraged and tracked; near misses are free lessons that reveal control weaknesses before harm occurs.

Inspection checklists should be based on regulations, standards, and past incident trends, and findings must be tracked to closure with assigned responsibility and due dates.

Audit findings are classified as major nonconformity, minor nonconformity, observation, or opportunity for improvement; corrective action plans are required for nonconformities.

Preservation of evidence includes photographs, sketches, witness statements, equipment logs, and securing physical items; chain of custody may be required.

Incident statistics should be analyzed by type, location, time, and severity to identify trends and prioritize prevention efforts.

Training needs analysis identifies gaps between required competencies and current knowledge, skills, and abilities (KSAs) for each role.

Adult learning principles (andragogy) emphasize relevance, problem-centered content, active participation, and immediate application.

Kirkpatrick's four levels of training evaluation: reaction, learning, behavior, and results.

Competency-based training requires demonstration of skill, not just attendance; records must show content, date, trainer, and evaluation method.

Safety communication tools include toolbox talks, safety meetings, bulletin boards, hazard alerts, and digital platforms; messages should be clear, timely, and two-way.

Safety culture maturity models typically progress from reactive (compliance-driven) to proactive and generative (learning-driven).

Behavior-based safety (BBS) programs observe and reinforce safe behaviors, but must not replace engineering controls or blame workers for system failures.

Orientation training must occur before work begins and cover workplace hazards, emergency procedures, and the right to refuse unsafe work.

Refresher training intervals are set by regulation or risk; high-hazard tasks (confined space, fall protection, respirators) often require annual retraining.

Emergency plan components: risk assessment, roles and responsibilities, communication, evacuation routes, assembly points, and post-incident recovery.

Emergency response priorities: life safety first, then incident stabilization, then property and environmental protection.

Drills and exercises should be conducted at planned intervals (often annually) and after plan changes; they must be documented and evaluated.

Evacuation time depends on occupant load, exit capacity, travel distance, and alarm notification; exit routes must remain unobstructed.

Emergency wardens/fire marshals are assigned to specific zones to direct evacuation and account for personnel at assembly points.

First aid requirements include trained attendants, stocked kits, and posted emergency numbers; the number of attendants is often set by worker count and hazard level.

Business continuity planning addresses critical functions, alternate sites, supply chain, and recovery time objectives (RTOs).

Spill response follows a tiered approach: minor spills handled by trained staff with spill kits; major spills require evacuation and specialized responders.

Post-emergency debriefs identify lessons learned and trigger plan revisions; corrective actions must be tracked to completion.

Exposure limits: ACGIH TLVs are health-based guidance; OSHA PELs are enforceable legal limits; jurisdictions may set their own OELs.

TWA (time-weighted average) = Σ(Ci × Ti) / 8 hours for an 8-hour shift; STEL is a 15-minute short-term exposure limit; ceiling limits must never be exceeded.

The hierarchy of hygiene controls: elimination/substitution, engineering (ventilation, enclosure), administrative (rotation, training), and PPE (respirators, gloves).

Respirator selection follows CSA Z94.4/OSHA 1910.134: fit testing (qualitative or quantitative), medical evaluation, and training are required before use.

Noise exposure: 85 dBA 8-hour TWA typically triggers a hearing conservation program; exchange rate is 3 dB (North America) or 5 dB (ISO/Europe).

Ergonomic risk factors include force, repetition, awkward posture, vibration, contact stress, and duration; assessment tools include RULA, REBA, and NIOSH lifting equation.

The NIOSH lifting equation calculates a recommended weight limit (RWL) = LC × HM × VM × DM × AM × FM × CM; the lifting index (LI) = load/RWL.

Hazardous substances enter the body via inhalation, ingestion, absorption, and injection; SDS (formerly MSDS) provide 16-section hazard information.

Heat stress controls include acclimatization, hydration, work-rest cycles, and monitoring WBGT; cold stress risks include hypothermia and frostbite.

Waste hierarchy, most to least preferred: prevention, reuse, recycling, recovery (energy), and disposal.

Hazardous waste must be characterized, labeled, stored in compatible containers, and manifested for transport to an approved facility.

ISO 14001 provides the framework for environmental management systems (EMS): policy, planning, implementation, checking, and management review.

Spill prevention includes secondary containment, drip trays, inspection schedules, and storm drain protection.

Air emissions are controlled through scrubbers, filters, and stacks; water discharges require permits and monitoring.

Environmental aspects and impacts are identified by linking activities/products/services to their potential environmental effects.

Waste segregation at source prevents contamination of recyclables and reduces disposal costs; color-coded bins and signage improve compliance.

Environmental incident reporting may be required to regulators within specific timeframes (e.g., immediate notification for reportable spills).

Sustainability initiatives include energy efficiency, water conservation, and green procurement; metrics track progress toward reduction targets.

OHS professionals must act with integrity, objectivity, confidentiality, and competence, and avoid conflicts of interest.

The duty to protect workers supersedes loyalty to an employer when the two conflict; escalation to regulators may be required.

Confidentiality applies to worker health information, investigation records, and proprietary data, subject to legal disclosure requirements.

Informed consent and privacy laws (e.g., PHIPA, PIPEDA) govern the collection, use, and disclosure of personal health information.

Roles: employers set policy and provide resources; supervisors direct work and enforce rules; workers comply and report; JHSC members monitor and recommend.

Professional conduct includes accurate recordkeeping, avoiding misrepresentation of qualifications, and reporting unsafe practices.

Whistleblower protections vary by jurisdiction; professionals should document concerns and follow internal escalation before external reporting.

Continuing professional development (CPD) maintains competence and is often a requirement for certification maintenance.

Ethical decision-making frameworks consider stakeholders, consequences, duties, and the law; transparency and documentation support defensible decisions.