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Commissioning Level 5
Integrated Systems Testing (IST)
IST fails utility power, cooling and controls on purpose to prove the data center can ride through. It is the riskiest day of commissioning. AAAT3 plans IST safety, scripts and stop rules so the test proves the building without hurting anyone or breaking anything.
- IST script review
- Failure scenario walkthroughs
- Stop rules
- Roles & communication
- Issue closure
By the numbers
Why IST must be planned to the minute
Share of impactful outages caused by power problems in 2025
Uptime Institute Outage Analysis, 2026Operators whose last major outage cost more than $100,000
Uptime Institute Outage Analysis, 2026Operators who say their last impactful outage could have been avoided with better management or processes
Uptime Institute Outage Analysis, 2026What’s included
Prove the whole building works
IST is where every system meets. We make sure the people are as ready as the gear.
Script review
Every step and expected result written and checked.
- Scenario by scenario review
- Expected readings and timings
- Safety holds and checks
- Script version control
Readiness and walkthroughs
No IST starts with open Level 4 issues.
- Level 4 issue closure check
- Tabletop walkthrough of each scenario
- Load bank and heat plans
- Equipment and area readiness
Roles and stop rules
Many people, many radios, one plan.
- Test director and roles
- Communication plan and radio channels
- Stop words and stop authority
- Post-test reset and lessons
Project management and consulting
Project management and consulting for IST
AAAT3 can manage IST readiness, review scripts for safety or run the floor during testing.
IST readiness management
Checks that every prerequisite is done before IST starts.
Best for: Projects nearing Level 5IST safety review
Independent safety review of scripts and scenarios.
Best for: Owners and Cx agentsFloor control during IST
AAAT3 leads on the floor for access, zones and stop rules.
Best for: Large IST events with many tradesTabletop facilitation
Walk through each scenario with all parties before testing.
Best for: First-time IST teamsIssue closure tracking
IST findings tracked to verified closure before turnover.
Best for: Projects with open IST issuesLessons learned
Post-IST review that feeds the next building.
Best for: Owners building multiple hallsHow it works
From scripts to signed IST
Review
Scripts and scenarios checked.
Ready
Level 4 closed, load banks set.
Walk
Tabletop of every scenario.
Test
Scenarios run under control.
Fix
Findings fixed and retested.
Sign
IST complete and documented.
Rule of thumb: no IST starts until every Level 4 issue is closed and every person on the floor knows the stop words.
Ways to work with us
Pick the level of support you need
Start small with a review, put a qualified person on site, or hand us the whole program. Every option is priced to your scope.
Quick start
IST script review
Safety review of your IST scripts.
- Script review
- Gap list
- Stop rules
- Report in days
Most popular
IST floor support
AAAT3 leads on the floor during IST.
- Access and zones
- Stop rules
- Communication
- Event log
Full program
IST management
We manage IST readiness, testing and closure.
- Readiness checks
- Tabletops
- Floor control
- Owner reporting
What you get
Deliverables
IST readiness checklist
Every prerequisite checked.
Script safety review
Findings and changes.
Communication plan
Roles, radios and stop words.
Event log
What happened, when.
Issue log
Findings tracked to closure.
Lessons learned
What to change next time.
Standards
Codes and standards we work to
Commissioning
3- ASHRAE Guideline 0
The commissioning processIndustry
- ASHRAE Standard 202
Commissioning process for buildings and systemsIndustry
- NFPA 110
Emergency and standby power testingIndustry
Safety
3- NFPA 70E
Electrical safety in the workplaceIndustry
- ANSI/TIA-942
Data center infrastructureIndustry
- EM 385-1-1
USACE safety and health requirementsFederal
Related data center services
Every phase of the build, one partner
Where we do this work
IST on the calendar? Get the scripts and floor plan reviewed before the first scenario.
Get an IST QuoteFAQ
Common questions
What is IST?
Integrated systems testing is commissioning Level 5. It tests the whole data center together, often by failing utility power or cooling on purpose to prove backups take over.
Who runs IST?
Usually the commissioning agent leads, with the owner, GC, trades and vendors on the floor. AAAT3 can support safety, readiness and floor control.
What are stop rules?
Agreed conditions and words that stop the test right away, with named people who have the authority to stop it.
How long does IST take?
It depends on the size and number of scenarios. Large facilities can take several days per hall.
Can AAAT3 review our IST scripts?
Yes. We do an independent safety review of scripts and scenarios before testing.
Get a quote for Integrated Systems Testing (IST)
Tell us about your project, location and start date. We reply with a plan and pricing.
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