Electrical GFCI Compliance Calculator

Calculator Inputs

Example data table

Examples are illustrative. Verify requirements for your jurisdiction and equipment.

Professional guidance article

1) Why GFCI compliance matters on construction sites

Construction power changes frequently, cords get moved, and tools are exposed to moisture and abrasion. A ground-fault circuit interrupter is designed to reduce shock risk by disconnecting power quickly when current leaks to ground. Personnel-grade devices are commonly Class A, which typically trip in the 4–6 mA range to protect workers during contact faults.

2) Locations that commonly trigger protection expectations

GFCI protection is most often expected where water or earth contact increases risk: bathrooms, kitchens, utility sink areas, outdoors, garages, crawl spaces, unfinished basements, rooftops, and pool/spa zones. This calculator flags those selections as “Required” and explains why in the result summary, helping you document location-based decisions consistently.

3) Temporary power: focus on 120V, 15/20A receptacles

Temporary distribution is a common jobsite setup, and many projects treat 120V, 15A and 20A receptacles as the highest priority for personnel protection. If you mark “Temporary power,” the tool applies stronger expectations and emphasizes testing cadence and record keeping, which inspectors frequently review.

4) Choosing the protection method

You can protect at the receptacle, at the breaker, or with a portable inline device. Breaker protection can cover multiple downstream outlets when wired correctly; receptacle protection can cover itself and downstream loads; portable devices are useful for temporary cords and portable distribution. The calculator records the method so your report matches field conditions.

5) Coverage calculation and why it affects scoring

Coverage is computed as Protected ÷ Total. The scoring model treats 95% or higher as acceptable for practical rounding, but the best target is full coverage when protection is required. If protection is missing while the status is “Required,” the score is capped to highlight the safety gap.

6) Wet and outdoor installations: hardware details

In exposed or wet conditions, weather-resistant (WR) devices and in-use covers are commonly expected. The tool marks “Weather readiness” as pass only when those selections match exposure. This keeps field packaging (WR, enclosure, cover) aligned with the environmental risk described in your inputs.

7) Testing and documentation: what reviewers look for

The checklist weights testing and records at 15 points, because a compliant device still needs verification. A strong practice is an initial test at installation and routine tests during active work. Record the date, location, tester, and any measured trip time so you can show a consistent process during audits.

8) Interpreting the score and acting on the output

The score is a weighted total (100 points): Protection (40), Class (10), Coverage (15), Weather readiness (10), Labeling (10), Testing & records (15). Use the “Recommended Actions” list to close gaps first that affect personnel safety, then improve documentation items like labeling and directory updates.

FAQs

1) Does “Required” mean my local inspector will always demand GFCI?

No. “Required” reflects common expectations for the selected location and conditions. Local amendments, the adopted code edition, and project specifications can change requirements. Use the result as documentation support, not a legal determination.

2) What does the score actually measure?

The score is a weighted checklist of protection presence, personnel-grade class selection, coverage, weather readiness, labeling, and testing/records. Higher scores indicate fewer safety and documentation gaps for the evaluated receptacles and conditions.

3) How is coverage calculated?

Coverage equals protected receptacles divided by total receptacles evaluated. If you use upstream protection (like a breaker), protected can equal total. Low coverage reduces the score because unprotected outlets increase shock exposure.

4) Should I choose breaker or receptacle protection?

Either can be appropriate. Breakers can protect multiple downstream outlets. Receptacles protect at the point of use and may protect downstream loads if wired correctly. Select the option that matches the installed design and labeling plan.

5) Why do WR devices and in-use covers matter outdoors?

Outdoor exposure increases moisture intrusion and corrosion risk. WR devices are built for wet environments, and in-use covers help maintain enclosure protection while cords are plugged in. The calculator treats them as key pass/fail items when exposed.

6) How often should GFCIs be tested on an active jobsite?

Many projects use an initial test at installation and routine checks during active work. Monthly testing is a common best practice on changing sites, but your safety program and local rules may require a different schedule.

7) Can I rely only on the “TEST” button?

The built-in test button is important, but some programs also use a dedicated tester and record trip behavior. Follow manufacturer instructions and your safety plan, and keep records so the compliance report supports inspections.