How many foot-candles does a warehouse need? Most warehouses require 20–30 foot-candles for general storage and picking aisles, and 30–50 foot-candles for packing benches and loading docks. OSHA sets a minimum of 5 fc — but that is a legal floor, not a productivity target.
Quick answer: Most warehouses need 20–30 foot-candles (200–300 lux) for general storage and picking. Active work areas, packing benches, and loading docks need 30–50 foot-candles (300–500 lux). High-rack storage above 25 ft requires 50+ foot-candles at floor level to compensate for height. OSHA minimum for general warehousing is 5 foot-candles — but that is a safety floor, not a productivity target.
Calculate foot-candles for your warehouse — free →
Warehouse foot-candle requirements by area type
5 fc
OSHA minimum
Legal minimum for general warehousing. Not a recommended design target — far too dim for productivity.
20–30 fc
General storage
Bulk storage, wide aisles, pallet storage. IES RP-7 recommended for general warehousing.
50 fc
Fine picking / packing
Pick-and-pack areas, label reading, quality inspection. Needed to reduce errors and eye strain.
| Warehouse area | Foot-candles (fc) | Lux equivalent | Standard |
|---|---|---|---|
| General bulk storage | 10–20 fc | 100–200 lux | IES RP-7 |
| Active picking aisles | 20–30 fc | 200–300 lux | IES RP-7 |
| Packing and shipping bench | 30–50 fc | 300–500 lux | IES / EN 12464 |
| Quality inspection area | 50–100 fc | 500–1,000 lux | EN 12464-1 |
| Loading dock / bay | 20–30 fc | 200–300 lux | IES RP-7 |
| Office within warehouse | 30–50 fc | 300–500 lux | EN 12464-1 |
| Stairways and corridors | 10 fc | 100 lux | OSHA 1910.119 |
| Emergency exit routes | 1–2 fc maintained | 10–20 lux | NFPA 101 / BS 5266 |
How to calculate foot-candles for a warehouse
The standard method is the lumen method: multiply target foot-candles by the floor area, then account for the fixture utilisation factor and maintenance factor.
Formula:
Number of fixtures = (Target fc × Area in sq ft × 10.764) ÷ (Lumens per fixture × UF × MF)
Example: 50,000 sq ft warehouse, 25 fc target, 40,000 lm high-bay fixtures, UF 0.75, MF 0.80
= (25 × 50,000 × 10.764) ÷ (40,000 × 0.75 × 0.80)
= 13,455,000 ÷ 24,000 = 56 fixtures
Number of fixtures = (Target fc × Area in sq ft × 10.764) ÷ (Lumens per fixture × UF × MF)
Example: 50,000 sq ft warehouse, 25 fc target, 40,000 lm high-bay fixtures, UF 0.75, MF 0.80
= (25 × 50,000 × 10.764) ÷ (40,000 × 0.75 × 0.80)
= 13,455,000 ÷ 24,000 = 56 fixtures
Foot-candles by warehouse size — quick reference
| Warehouse size | Target (25 fc) | Fixtures at 20,000 lm | Fixtures at 40,000 lm |
|---|---|---|---|
| 10,000 sq ft | 25 fc general | 18–22 fixtures | 10–12 fixtures |
| 25,000 sq ft | 25 fc general | 44–55 fixtures | 22–28 fixtures |
| 50,000 sq ft | 25 fc general | 88–110 fixtures | 44–56 fixtures |
| 100,000 sq ft | 25 fc general | 175–220 fixtures | 88–110 fixtures |
| 200,000 sq ft | 25 fc general | 350–440 fixtures | 175–220 fixtures |
Assumes UF 0.70–0.80, MF 0.80. Actual counts require photometric calculation with fixture-specific IES data.
Choosing the right high-bay fixture
Warehouse ceiling height determines fixture type. The wrong fixture at the wrong height wastes energy and delivers uneven light:
| Ceiling height | Fixture type | Typical output | Notes |
|---|---|---|---|
| 12–20 ft | LED linear high bay | 10,000–25,000 lm | Rectangular fixture, good for lower ceilings and wide aisles |
| 20–30 ft | LED UFO high bay | 20,000–40,000 lm | Round fixture, concentrated beam — most common choice |
| 30–40 ft | LED UFO high bay (high output) | 40,000–60,000 lm | Needs narrower beam angle (60–90°) to reach floor effectively |
| 40 ft+ | LED high mast / sport | 60,000–150,000 lm | Specialist fixtures — requires photometric design |
Beam angle matters at height: At 30 ft mounting height, a 120° beam spreads light over a large area — delivering fewer foot-candles at floor level. Use a 60–90° beam at heights above 25 ft to concentrate light where it’s needed. The Warehouse Lighting Calculator selects the correct beam angle automatically.
Foot-candles vs lux — converting between the two
Foot-candles are the US standard. Lux is the metric (SI) standard used in Europe, Australia, and most international specifications. They measure the same thing — illuminance — in different units.
| Foot-candles (fc) | Lux equivalent | Typical application |
|---|---|---|
| 5 fc | 54 lux | OSHA minimum — emergency only |
| 10 fc | 108 lux | Bulk storage, rarely accessed areas |
| 20 fc | 215 lux | General warehousing, wide aisles |
| 30 fc | 323 lux | Active picking, loading docks |
| 50 fc | 538 lux | Packing bench, fine pick areas |
| 100 fc | 1,076 lux | Quality inspection, detailed assembly |
To convert: Multiply foot-candles × 10.764 to get lux. Divide lux ÷ 10.764 to get foot-candles.
OSHA and IES requirements for warehouse lighting
OSHA 29 CFR 1910.119 sets minimum foot-candle levels for general industry:
| Location | OSHA minimum (fc) | IES recommended (fc) |
|---|---|---|
| General warehousing | 5 fc | 20–30 fc |
| Corridors, hallways | 5 fc | 10 fc |
| Stairways | 10 fc | 20 fc |
| First aid stations | 30 fc | 50 fc |
| Office areas | 30 fc | 30–50 fc |
OSHA vs IES: OSHA minimums are the legal floor — lighting below these levels can result in citations and fines. IES (Illuminating Engineering Society) recommendations are best-practice targets for productivity and worker safety. Always design to IES levels — OSHA minimums are not adequate for active warehouse operations.
Energy cost and ROI — LED high bays vs old metal halide
Most warehouses upgrading from metal halide (MH) or high-pressure sodium (HPS) to LED see significant savings:
| Technology | Watts (20,000 lm) | Annual cost (100 fixtures, 16h/day) | Lifespan |
|---|---|---|---|
| Metal halide | 400W | $35,000–40,000/yr | 15,000–20,000 hrs |
| High-pressure sodium | 350W | $30,000–35,000/yr | 20,000–24,000 hrs |
| LED high bay | 150–200W | $13,000–17,000/yr | 50,000–100,000 hrs |
| LED saving vs MH | 55–65% less | $18,000–27,000/yr saved | 3× longer life |
Frequently asked questions
How many foot-candles does a warehouse need?
The IES recommends 20–30 foot-candles for general warehouse storage and picking aisles, 30–50 fc for packing and shipping areas, and 50–100 fc for inspection areas. OSHA requires a minimum of 5 fc for general warehousing — this is a legal minimum only, not a productivity standard.
What is a foot-candle in a warehouse context?
A foot-candle (fc) is a unit of illuminance — it measures how much light falls on a surface. One foot-candle equals the light from one candle falling on one square foot of surface one foot away. In metric, 1 foot-candle = 10.764 lux. Warehouses are typically designed to 20–30 fc for general areas.
How do I measure foot-candles in my warehouse?
Use a light meter (lux meter or foot-candle meter) — inexpensive digital versions cost $30–80. Hold it horizontally at 2.5–3 ft above floor level (working height) and take readings at multiple points across the floor. Average the readings. High-rack storage areas should be measured at the lowest shelf level too.
How many lumens do I need per square foot in a warehouse?
For 25 foot-candles (a standard warehouse target), you need roughly 25 × 10.764 = 269 lux at floor level. Working backwards through typical UF (0.70) and MF (0.80) values, you need approximately 480 lumens per square foot of installed fixture output — or about 0.5W/sq ft with 100 lm/W fixtures.
What beam angle for warehouse high bays?
Use 90–120° beam angles for ceilings below 20 ft — wide spread covers more floor area per fixture. For ceilings 25–35 ft, use 60–90° — narrower beam concentrates lumens at floor level where they’re needed. For very high ceilings (35 ft+), 60° or narrower delivers the most floor-level foot-candles per fixture.
Calculate foot-candles for your warehouse
Enter your warehouse dimensions, ceiling height, and target foot-candles — the calculator returns fixture count, spacing, pole layout, and annual energy cost.
Open the Warehouse Lighting Calculator →