In the lifecycle of a construction project, commissioning is often seen as the final lap—a sign that the heavy lifting is done and the finish line is in sight. But this perception can be dangerously misleading. Commissioning is not the end of work—it’s a critical phase of transition, where systems are energized, tested, and verified. And while the tools may be quieter, the risks are not.
The Commissioning Blind Spot
Commissioning is a complex, multi-disciplinary process that ensures building systems perform as intended. It involves:
- Prefunctional checks (verifying installation and readiness)
- Site walks (visual inspections and coordination)
- Functional performance testing (system operation under real conditions)
Despite its importance, safety during commissioning is often overlooked. Why? Because it doesn’t “look” like traditional construction. But this mindset can lead to serious incidents—especially when systems are being activated for the first time.
Phase-by-Phase Breakdown: Where the Hazards Hide
Prefunctional Checks: The Calm Before the Storm
This phase involves verifying that equipment is installed correctly and ready for operation. It may include:
- Checking electrical terminations
- Verifying ductwork and piping
- Inspecting control wiring and sensors
Key Hazards:
- Arc flash and electrical shock from live panels or improperly isolated circuits
- Confined space entry in mechanical rooms or crawlspaces
- Stored energy in pressurized systems (e.g., air, water, refrigerants)
- Slips, trips, and falls due to cluttered or unfinished areas
Safety Tips:
- Require LOTO (Lockout/Tagout) procedures even during “simple” checks
- Use arc-rated PPE when opening panels or testing circuits
- Conduct confined space assessments and ensure proper permitting
- Keep walkways clear and enforce good housekeeping
2. Site Walks: Familiar Territory, Unfamiliar Risks
Site walks are often conducted by commissioning agents, engineers, and owners. These walks may seem routine, but they often occur in partially completed environments.
Key Hazards:
- Unmarked hazards like open panels, exposed wiring, or missing handrails
- Temporary lighting or power creating visibility and shock risks
- Uncoordinated access to active work zones
Safety Tips:
- Treat site walks like any other jobsite activity—require PPE
- Use spotters or escorts for visitors unfamiliar with the site
- Post clear signage for energized or restricted areas
- Include site walk safety in the daily pre-task plan
3. Functional Testing: Systems in Motion
This is where systems are brought to life—HVAC units start up, fire alarms are tested, elevators move, and automation systems begin to operate. It’s a high-risk, high-coordination phase.
Key Hazards:
- Unexpected equipment movement (e.g., fans, dampers, pumps)
- Live testing of fire suppression, alarms, and emergency systems
- Noise and vibration from mechanical systems
- Multiple trades working simultaneously in tight spaces
Safety Tips:
- Develop a functional testing safety plan with roles and responsibilities
- Use checklists to verify readiness before energizing systems
- Ensure real-time communication between all involved parties
- Pause testing if unauthorized personnel enter the area
Why Safety Gets Overlooked—and How to Fix It
Common Pitfalls:
- “It’s just testing—what could go wrong?”
- Reduced manpower and oversight
- Pressure to meet turnover deadlines
- Lack of clarity on who owns safety during commissioning
Solutions:
- Assign a commissioning safety lead to coordinate efforts
- Include commissioning in the project safety plan and JHAs
- Hold daily commissioning coordination meetings
- Require permits to test for high-risk systems (e.g., fire suppression, elevators)
Commissioning Safety Is Everyone’s Responsibility
Commissioning is a team sport. It involves general contractors, subcontractors, commissioning agents, engineers, and owners. Safety during this phase depends on clear communication, shared accountability, and proactive planning.
Key Takeaways:
- Don’t assume safety ends when construction does
- Treat commissioning as a distinct phase with unique risks
- Build safety into every step—from prefunctional checks to final sign-off
- Empower your teams to speak up and stop work if something feels unsafe
Final Word: Safety Is the Last System You Commission
The systems may be new, the space may be clean, and the tools may be packed up—but the risks are real. By prioritizing safety during commissioning, we ensure that the building isn’t just operational—it’s safe for everyone who enters it.
