Commission exterior security lighting for the people who must use and maintain it

Source facts: exterior lighting is designed around tasks and maintained conditions

The Department of Defense’s UFC 3-530-01, Interior and Exterior Lighting Systems and Controls, published February 9, 2023 and updated by Change 1 on December 15, 2023, provides design requirements based on the Illuminating Engineering Society lighting library and federal energy policy. It covers exterior applications, calculation, equipment, controls, commissioning, and maintenance considerations.

The UFC treats lighting as more than fixture wattage. Design criteria vary by application and consider illuminance, uniformity, vertical and horizontal tasks, glare, light trespass, color qualities, controls, energy use, environmental conditions, and light loss over time. Maintained performance matters because lamp or LED depreciation, dirt, component failure, weather, and surface changes can reduce the result after installation.

The UFC is mandatory within its stated Department of Defense scope; it is not automatically the code for a private property. Local electrical, energy, building, environmental, accessibility, zoning, and dark-sky rules, the adopted design standard, and qualified professional judgment determine a commercial project. Numeric criteria should come from the applicable task and standard, not a generic “security foot-candle” copied between sites.

DSE recommendation: accept the nighttime task, not the fixture schedule

Divide the site into operating zones and assign each a human task: find an entrance, read a sign, use a credential reader, see a step or obstacle, recognize another person at conversational distance, inspect a vehicle or delivery, observe a gate condition, patrol a boundary, reach an exit discharge, or safely restore equipment. Record who performs the task, viewing direction, distance, hours, adaptation state, and degraded conditions.

Survey the existing night scene. Walk after full darkness with operations, facilities, security, accessibility, and the lighting designer. Mark shadows, glare sources, reflected light, spill onto neighbors or roads, vegetation, snow storage, parked vehicles, signs, level changes, and areas where one bright source makes adjacent space harder to see.

Design to maintained conditions. Require calculations and assumptions for the applicable task plane, uniformity, surface reflectance, dirt and depreciation, temperature, mounting, shielding, controls, and maintenance. Distinguish initial output from the expected condition immediately before scheduled service.

Coordinate physical placement. Confirm poles and luminaires do not create climbing aids, vehicle conflicts, blocked accessible routes, gate interference, door-clearance problems, maintenance hazards, or responder obstructions. Protect accessible disconnects and control equipment according to the approved electrical design.

Test every control state. Exercise schedules, photocells, occupancy or adaptive controls, manual overrides, event modes, curfew levels, power interruption, restart, and emergency or standby operation where provided. Verify who receives a failure report and how the area is protected until repair.

Measure and walk. Have the qualified team measure representative horizontal and vertical points using the approved method, then perform each defined task from the real approach direction. Check darkest points, transitions, perimeter edges, face-level glare, wet pavement, reflective signs, and the view from occupied neighboring property or public roads.

Preserve the accepted baseline. Record fixture and driver, optics, mounting and aim, control settings, measurement grid, weather, surface condition, readings, task results, exceptions, and night photographs. Future maintenance needs a repeatable reference, not a statement that the lot once looked bright.

Create inspection triggers for failed or cycling luminaires, shifted aim, dirty lenses, damaged shields, vegetation growth, construction, changed parking, new signage, repeated complaints, and control overrides. Define safe access for cleaning and replacement, compatible parts, and temporary lighting. Recheck task performance after material changes rather than replacing components and assuming equivalence.

Avoid judging quality from directly beneath a pole. The person approaching the site experiences contrast, adaptation, glare, and shadow across the whole path. The accepted system should help people make the intended physical decisions while remaining maintainable, energy-conscious, and respectful of adjacent spaces. More light is not automatically more security; usable, controlled, measured light is.

Official references

U.S. Department of Defense, UFC 3-530-01, Interior and Exterior Lighting Systems and Controls, Change 1, December 15, 2023.

Whole Building Design Guide, Unified Facilities Criteria public library, current publication status reviewed August 11, 2026.