| Publisher | IEEE |
|---|---|
| Type | Guide |
| Scope | A method for estimating arcing current, incident energy and arc flash boundary for three-phase AC electrical equipment, based on laboratory test data. |
| Who uses it | Power system engineers, consulting engineers, facility electrical engineers, software tool users and safety professionals responsible for arc flash studies. |
| Edition note | IEEE 1584-2018 is the current major revision and introduced the present arc model. Refer to IEEE for any later amendments or revisions. |
What It Is
IEEE 1584 is the IEEE guide used to calculate the thermal energy an arc flash can deliver to a worker. It provides empirically derived equations, fitted to an extensive program of laboratory arc tests, that estimate the arcing current, the incident energy at a specified working distance and the distance at which incident energy falls to the threshold for a second-degree burn, known as the arc flash boundary.
The 2018 revision replaced the earlier model with a significantly more detailed one. It accounts for the physical configuration of the electrodes inside equipment, the enclosure size, the system voltage and the conductor gap, and it requires calculations at more than one arcing current to capture the effect of protective device operating time. The guide is used within a complete arc flash study that also includes a short-circuit study, a protective device coordination review and accurate field data collection.
Why It Matters
NFPA 70E requires an arc flash risk assessment and permits PPE to be selected from an incident energy analysis. In practice, that analysis is almost always performed using IEEE 1584, typically inside commercial power system software. The results appear on equipment labels and drive decisions about PPE, work permits, remote operation and engineering changes such as faster protection or maintenance switching.
The guide is only as good as its inputs. Incorrect utility fault data, outdated one-line diagrams, wrong protective device settings or unrealistic working distances can produce labels that understate the hazard. Engineers who understand the model's assumptions and limits produce studies that protect people; those who treat it as a black box can create a false sense of safety.
Key Concepts
- Arcing current — the current that flows through the arc itself, lower than the bolted fault current because of arc impedance; it determines how long the upstream protective device takes to clear.
- Incident energy — the thermal energy per unit area received at a defined working distance, usually expressed in calories per square centimeter, used to select arc-rated PPE.
- Arc flash boundary — the distance from the arc source at which incident energy drops to the onset level for a second-degree burn on bare skin.
- Electrode configuration — the 2018 model distinguishes vertical and horizontal conductor arrangements, in boxes or open air (VCB, VCBB, HCB, VOA, HOA), because each directs arc energy differently.
- Working distance — the assumed distance between the arc and the worker's face and chest; it varies with equipment type and strongly affects results.
- Arcing current variation — a correction that recalculates energy at a reduced arcing current, because slower device operation at lower current can produce higher energy.
- Model range of applicability — the guide defines the voltages, fault currents, gaps and configurations covered by test data; outside that range, engineering judgment and other methods are required.
Who Should Know It
- Power system and protection engineers performing arc flash studies
- Facility electrical engineers maintaining one-line diagrams and labels
- Safety managers interpreting study results for the electrical safety program
- Maintenance planners who rely on labels to select PPE and work methods
- Engineering students and graduates entering power system analysis
Related Standards
- NFPA 70E — requires the arc flash risk assessment that IEEE 1584 calculations support.
- CSA Z462 — the Canadian workplace electrical safety standard, which also relies on incident energy analysis.
- IEEE C37 Series — covers the switchgear, breakers and relays whose ratings and clearing times are key study inputs.
- OSHA 29 CFR 1910.269 — requires utilities to estimate incident energy for workers exposed to arc hazards.
How ASEEE Uses It
ASEEE power systems and electrical safety programs map learning outcomes to the concepts in IEEE 1584: data collection, short-circuit and coordination inputs, interpretation of incident energy results and the limits of the model. Assessments focus on reasoning about results and inputs rather than reproducing equations. See related ASEEE programs.
ASEEE Programs Referencing This Standard
- Advanced Power System Analysis with ETAP
- Arc Flash Hazard Analysis and Risk Assessment
- Electrical Control Person
- Power System Analysis Using ETAP
- Safe Isolation for Low and High Voltage Systems
- Senior Authorized Electrical Person
Educational summary only. ASEEE is not the publisher of this document and this page does not reproduce or replace it. Always consult the current official edition from IEEE for requirements.