Warehouse lighting at 8 to 14 m: beam and calculation
Rack and floor storage at 8 to 14 m: the ShNK 2.01.05-24 norm, light distribution curve, flux per square metre, a worked example on 5,000 m² and HPS 250 W to Prom by the IES file figures.
Contents
A warehouse with an 8 to 14 m ceiling is calculated not by area but by aisle: light has to travel from the height down to the floor and to the label on the bottom shelf without spreading over the upper tiers. Below is the method we use for such warehouses, with figures you can check against the IES files and the code. The norms and a typical layout for 3,000 m² are described on the warehouse lighting page; here it is height, light distribution curve and calculation.
What the norm requires
ShNK 2.01.05-24 (Annex 9, Table 2, clause 65) sets, for warehouses with rack storage, 50 lx on the floor in the storage zone, 75 lx on the racks in the vertical plane, 200 lx at receiving, dispatch and transport zones at 0.8 m, and 300 lx at goods sorting (clause 70). For receiving and sorting UGR is limited to 25 and percent flicker to 20%. Warehouses of bulky goods and loose materials: 75 lx on the floor (clause 67).
The technical specifications of logistics operators almost always ask for more than the norm in the aisles: 100 to 150 lx on the floor, so that the picker can read the marking and the scanner reads at the first pass. The norm is the lower bound; the specification is the design level.
Mounting height and light distribution curve
Height determines which light distribution curve will put the light into the aisle. Three cases.
- Floor storage, wide driveways, 8 to 10 m. A cosine or semi-wide curve suits: the light lies evenly, and the spacing between luminaires can exceed the height.
- Racks of 8 to 9 m, aisle 3 to 4 m, mounting at 10 to 12 m. The luminaire hangs over the aisle axis, and a wide curve is harmful here: half the flux goes onto the ends of the upper tiers, and a shadow remains on the floor between the racks. A deep or concentrated curve (classes G and K) is needed, or a linear luminaire along the aisle.
- Overhead crane or mezzanine. The luminaire cannot hang at a convenient height, and the layout is calculated from what is left.
The suspended Prom industrial luminaire is designed for heights from 7 m, IP54. By the 2018 IES file its half-intensity beam angle is 74° × 106° in the C0 × C90 planes: a curve for floor storage and driveways. For narrow aisles at 12 m we calculate the spacing along the aisle in DIALux, and if uniformity on the floor fails, we put Line in a run over the aisle at up to 10 m and leave Prom over the driveways and the receiving zone. What exactly the file gives on the floor can be seen in the IES viewer on the site without DIALux.
How much flux per square metre
An estimate by the utilisation factor method: E = F × N × UF × MF / S. For a warehouse with high racks the utilisation factor UF is low, 0.4 to 0.5: the racks intercept the light. The maintenance factor MF for a clean room is 0.67 (ShNK, Annex 1, Table 3; safety factor 1.5). At UF 0.45 and MF 0.67 the flux needed per square metre of floor area:
| Zone | Level, lx | Flux, lm/m² | Prom 200W (26,000 lm) per 1,000 m² | W/m² |
|---|---|---|---|---|
| Storage to the norm, floor | 50 | 170 | 6 to 7 | 1.3 |
| Aisles to a typical specification | 150 | 500 | 19 to 20 | 3.9 |
| Receiving and dispatch | 200 | 670 | 26 | 5.1 |
| Sorting | 300 | 1,000 | 38 to 39 | 7.7 |
Luminaire flux is taken from the 2018 IES files: Prom 100W 13,000 lm, Prom 150W 19,500 lm, Prom 200W 26,000 lm, all around 130 lm/W. The table shows the order of magnitude; the count for a plan comes only from the calculation.
Example: a 5,000 m² warehouse, mounting at 12 m
A warehouse of 100 × 50 m, 9 m racks, eight aisles, mounting at 12 m. Specification: 150 lx on the floor in the aisles, 200 lx at a 500 m² receiving zone. Operation 14 hours a day, 300 days a year.
Before: 100 luminaires with HPS 250 W at 275 W each with ballast (250 × 1.10 under the EU energy labelling convention for discharge lamps on external control gear), 27.5 kW. By the rating of new lamps (30,000 lm, Lisma DNaT 250-5M) the same assumptions give ≈ 180 lx over the area: the old scheme was calculated “with a margin”, but a round reflector at 12 m puts pools of light under the luminaires and shadow between the racks, and Ra around 25 does not let you read colour marking.
After: 150 lx needs 500 lm/m², that is 2.5 million lm over the area, which is 96 Prom 200W; over receiving the run is densified to 200 lx. In total ≈ 100 luminaires and ≈ 20 kW instead of 27.5 kW: 27% less. A one-for-one replacement of HPS 250 W with Prom 200W gives the same: 275 W against 200 W, flux 30,000 against 26,000 lm, 13% less; the calculator shows a warning here, and without a recalculation for the aisles the replacement must not be done that way. Over a year at 4,200 hours the difference is ≈ 31,500 kWh; at a tariff of 1,100 UZS per kWh including VAT (Cabinet of Ministers Resolution No. 243 of 15 May 2026) that is ≈ 35 million UZS; at the price from the model card that is ≈ 4 years. The saving is calculated under the stated assumptions.
Where the gain is larger. If the specification is limited to the norm (50 lx on the floor and 75 lx on the racks), flux per square metre drops threefold, and the count of luminaires is then determined by vertical illuminance and uniformity in the aisles rather than by the average level. That is what DIALux calculates: request a calculation from the warehouse plan free of charge; our IES files go into it.
Emergency lighting: in brief
ShNK 2.01.05-24 requires escape lighting on the main passages of industrial buildings where more than 50 people work, and in rooms without daylight (clause 141). The minimum on the floor of escape routes is 0.5 lx, on open areas 0.2 lx (clause 148), uniformity Emin/Emax no worse than 1:40 (clause 149). Standby lighting, where work continues when the normal lighting fails, is not less than 5% of the norm but not below 2 lx inside a building (clause 146). LED sources for emergency lighting are expressly permitted (clause 151). In a warehouse this is usually a separate group of luminaires with an emergency power unit along the aisles and at the gates; in the design it is calculated as a separate layer.
Frequently asked questions
Which luminaire is needed for a 12 m warehouse?
A suspended one with a deep or concentrated curve over narrow aisles and a cosine curve over driveways; power 150 to 200 W at 19,500 to 26,000 lm by the IES file. The count and spacing come from a calculation for the rack plan, not from the height alone.
Can HPS 250 W be replaced with a 100 W LED luminaire?
Not by flux: 13,000 lm for Prom 100W against 30,000 lm for the lamp. Such a replacement is appropriate only if the calculation to the norm shows that the old scheme is over-lit several times over. The calculation decides, not the power.
How many watts per square metre to allow?
At UF 0.45 and MF 0.67, about 1.3 W/m² for 50 lx, 3.9 W/m² for 150 lx, 5.1 W/m² for 200 lx with luminaires of 130 lm/W efficacy. In a warehouse with low racks and a light ceiling UF is higher and the power density lower.
How to accept a warehouse after installation?
A lux-meter measurement over a grid of points on the aisle floor and on a rack, without daylight. At acceptance ShNK 2.01.05-24 (clause 178, Table 26) requires not less than 0.9 × Kz × En of the design level; the second document is the meter reading for the lighting group for a month before and after.