TL;DR

Ampere Interrupting Capacity (AIC): Maximum fault current a protective device can safely interrupt without destruction. Must equal or exceed available fault current.

By Valenke Exam Prep Team·Last updated 2026-06-02

Ampere Interrupting Capacity (AIC)

MASTER ELECTRICIAN

Definition

Maximum fault current a protective device can safely interrupt without destruction. Must equal or exceed available fault current.

Clinical Significance

For electricians, ampere interrupting capacity (aic) has direct implications under NEC Article 310 (Conductors for General Wiring). Key provisions include:

Table 310.16: allowable ampacities of insulated conductors
310.15(C): derating for more than 3 current-carrying conductors
Temperature correction factors for ambient over 30 C

Troubleshooting

Troubleshooting issues related to ampere interrupting capacity (aic):

No AFCI protection: Bedrooms and living areas in new construction require AFCI per 210.12
Improper grounding: Bootleg ground (jumping neutral to ground at receptacle) or missing EGC
Backstab connections: Push-in connections on receptacles fail more often than screw terminals, poor practice though not a code violation
Overcrowded box: Box fill exceeds allowable volume per 314.16, common in renovation work

Practical Example

Electrical Calculation: Power (DC)

Formula: P = E x I = I squared x R = E squared / R

Variables: P (watts), E (volts), I (amps), R (ohms)

Example: 120V x 15A = 1,800W

Common Errors

Common mistakes related to ampere interrupting capacity (aic) that electricians must avoid:

Double-tapped breaker: Two conductors on a single-pole breaker not rated for multiple conductors
Missing GFCI: Bathroom, kitchen, garage, outdoor, and crawl space receptacles require GFCI per 210.8
Backstab connections: Push-in connections on receptacles fail more often than screw terminals, poor practice though not a code violation
Missing nail plates: Cables through studs within 1.25 inches of edge require steel plates per 300.4

Patient Communication

Clear communication about ampere interrupting capacity (aic) with patients, families, and the healthcare team is essential. Use standardized handoff tools (SBAR) for shift changes and transfers. Verify understanding by asking the patient to repeat key information back to you.

Why It Matters

AIC ratings and coordination tested on ME exam.

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Frequently Asked Questions

What safety requirements apply to ampere interrupting capacity (aic)?▼

For ampere interrupting capacity (aic): NFPA 70E arc flash boundaries: limited approach, restricted approach, prohibited approach based on voltage and available fault current. Working space clearances per 110.26: minimum 3ft depth, 30 inch width, 6.5ft headroom for under 600V equipment.

What formulas are needed to calculate ampere interrupting capacity (aic)?▼

For ampere interrupting capacity (aic): Power (DC): P = E x I = I squared x R = E squared / R. Variables: P (watts), E (volts), I (amps), R (ohms). Example: 120V x 15A = 1,800W.

What NEC articles cover ampere interrupting capacity (aic)?▼

For ampere interrupting capacity (aic): Article 310 (Conductors for General Wiring): Table 310.16: allowable ampacities of insulated conductors. Article 430 (Motors): 430.6: use FLC from Table 430.248/250 not nameplate for conductor/OCP sizing.