“Don’t start until it’s safe to start—your permit to work system is the proof.”

Certain high-risk jobs—like maintenance on live equipment, working at heights, or entering confined spaces—require controls beyond normal procedures. This is where a permit to work system (PTW) becomes critical. A PTW is a formal authorization and control process that confirms hazards are identified and controlled before work begins. Sadly, many serious incidents have occurred because permit systems were ignored or poorly managed—from contractors starting work without authorization to catastrophic failures linked to miscommunications during permitting. These lessons underline a simple truth: a robust, followed-in-practice permit to work system can be the difference between a routine job and a fatal accident.

If your organization aims to strengthen safety performance, implementing or improving a permit to work system is essential. Below are seven practical steps to establish an effective PTW, whether you’re starting from scratch or auditing an existing process.

Step 1: Define Scope and Types of Permits

Begin by clearly defining which activities require permits and by standardizing permit types (e.g., hot work, confined space entry, electrical work, excavation, working at height). Analyze your operations to decide where formal control is necessary—maintenance on energized panels, line-breaking on toxic or flammable services, entry into vessels, etc.
Set roles and responsibilities upfront: who issues permits (safety officer/area manager), who receives and executes them (performing authority/supervisor), and who provides higher-level authorizations for critical jobs. Standardized forms/checklists tailored to each permit type ensure consistency and completeness in your permit to work system.

Step 2: Identify and Assess Hazards for Each Job

A PTW is effectively a job-specific risk assessment. Each time a permit is raised, collaboratively identify hazards from the task and environment (e.g., flammable vapors, energized parts, toxic exposure, elevation risks).
Assess the risk and determine controls in line with HIRA principles. For example: isolate and depressurize lines, purge and gas-test, secure scaffolds, mandate fall protection, and document all requirements on the permit. Structured prompts (“Isolated and drained? LOTO applied? Gas test readings?”) help ensure no critical risk is overlooked and reinforce the rigor of your permit to work system.

Step 3: Specify Precautions and Control Measures

Translate the assessment into actionable controls following the Hierarchy of Controls—eliminate/substitute where possible, then engineering, administrative, and PPE.
Document isolations with precision: breaker numbers locked off, valves closed and tagged, verifications performed by named personnel. Many serious incidents originate from incomplete isolation or miscommunication, so your permit to work system should require a double-check and visible confirmation that equipment is safe to work on.
Include in-task precautions (continuous gas monitoring, fire watch, ventilation, barricading) and manage simultaneous operations (avoid incompatible jobs or define coordination rules). The permit becomes the single source of truth for how the job will be performed safely.

Step 4: Train for Competence in the PTW Process

A permit to work system only works when people understand and believe in it. Train all issuers, receivers, and workers on when a permit is required, how to request/complete one (paper or digital), and what each section means.
Use realistic scenarios and drills to surface common pitfalls, and tailor materials to local languages and literacy levels. Emphasize expectations: no job starts until the permit is fully authorized and the team has signed on. Competence and clarity drive compliance.

Step 5: Authorization and Communication

Authorization is the second pair of eyes. After hazards and controls are recorded, a responsible person (e.g., shift manager or safety officer) reviews the permit for completeness and adequacy before signing. Very high-risk jobs may require multiple authorizations.
Communication turns the document into action: hold a toolbox talk so every worker understands hazards, isolations, gas-test values, and specific controls. Inform adjacent teams of active permits, display permits at the job site, and use visible cues (boards, tags) to prevent interference. In a mature permit to work system, authorization and communication are inseparable.

Step 6: Supervision and Monitoring During Work

Issuing the permit is not the finish line—it’s the start of oversight. Supervisors and safety watch personnel should verify that controls are in place and maintained: fire watch attentive, gas testing continuous and logged, PPE used correctly, barricades intact.
Pause or stop work if conditions change (weather, scope drift, unexpected readings). Coordinate concurrent permits to avoid conflicts (e.g., hot work near volatile cleaning tasks). Whether paper-based or digital, your permit to work system should enable real-time visibility and prompt checks throughout the job.

Step 7: Closure and Post-Job Review

On completion (or at shift end if extending), clean the area, verify removal of tools/temporary connections, and return the equipment to a safe operational state. Close the permit formally and log the closure. If work continues, reissue/renew the permit with a fresh hazard review—no open-ended permits.
Capture lessons learned: near misses, surprises, and improvement ideas. Over time, these reviews refine your permit to work system and feed design or procedural fixes (e.g., adding accessible lock points, tool lanyard rules).

Conclusion

A well-implemented permit to work system is a cornerstone of industrial safety. By defining clear scope and roles, enforcing rigorous hazard assessment, documenting isolations and controls, ensuring competent authorization and communication, maintaining active supervision, and closing with learning, organizations reduce the likelihood and severity of incidents during non-routine or high-risk work.
Regulatory expectations and management standards (such as ISO 45001) align with this approach, emphasizing safe systems of work for hazardous activities. While some may perceive permitting as “extra paperwork,” digital workflows can streamline the process and elevate assurance.

How OQSHA helps: OQSHA digitizes the permit to work system end-to-end—requests, approvals, conflict checks, mobile gas-test logging, isolation photos, and audit-ready trails—so safety teams can move faster without compromising control. If it’s not safe, we don’t start—and the permit is how we know.