Iluminação Lumens por m²

Sizing lighting in lumens per area

You size lighting in lux (lumens per m²). NBR ISO 8995 puts the recommended level at roughly 150–300 lux in a living room, 300–500 lux in a kitchen, 500 lux at an office and 1,000+ lux in surgical rooms. Say you have a 12 m² living room and you're aiming for 200 lux. That's 12 × 200 = 2,400 lumens, about three 9 W LED bulbs (each one around ~800 lm, the equivalent of a 60 W incandescent). Spread those lumens across a few fixtures so you don't end up with shadows and glare.

Applications

This shows up in residential and commercial lighting design, in office layouts that have to meet NR-17 (ergonomics), and across architecture, retail and industrial work. Efficiency varies a lot by source: modern LED bulbs put out ~80–110 lm/W, halogen sits around ~15 lm/W and incandescent only ~10 lm/W. Color temperature matters too. Go 2700–3000 K (warm) in living areas, 4000 K (neutral) in kitchens and offices, and 5000–6500 K (cool) in workshops.

FAQ

Lumens or watts? Go by lumens. Watts tell you how much energy a bulb draws, not how bright it is, which is why a 9 W LED can match a 60 W incandescent.

One central fixture or several? Several is better. When you spread the lumens around, the shadows over counters and tables disappear.

Does ceiling height affect it? It does. Once you're above 3 m, bump the target lux up by 20–30 %, since part of the flux gets lost on the way down.