Convert Foot-candles to Lumens per square yard

Convert Foot-candles (fc) to Lumens per square yard (lm/yd²) instantly and accurately.

Foot-candles (fc)
Lumens per square yard (lm/yd²)

Conversion Formula

lm/yd² = fc × 9

About Foot-candles

The foot-candle (fc) equals 1 lm/ft² ≈ 10.764 lx. Standard in North American lighting design: IESNA recommends 30-50 fc for general offices, 50-100 fc for retail displays, 12-16 fc for cinema screens. Still the dominant unit in the US, Canada and some other countries. 1 fc = 1/0.09290304 lx.

About Lumens per square yard

The lumen per square yard (lm/yd²) equals 1/0.83612736 lx ≈ 1.196 lx. Used occasionally in UK outdoor area lighting specifications alongside foot-candles. A 3 lx minimum car-park standard equals ~2.5 lm/yd²; a 100 lx sports-field requirement ~84 lm/yd². 1 lm/yd² = 1/0.83612736 lx.

Quick Reference Table

Foot-candles (fc)Lumens per square yard (lm/yd²)
1 fc9 lm/yd²
2 fc18 lm/yd²
5 fc45 lm/yd²
10 fc90 lm/yd²
25 fc225 lm/yd²
50 fc450 lm/yd²
100 fc900 lm/yd²

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