In Canada we typically use FC(foot-candles). But on the odd occasion a Canadian company comes to us with a lux reading and prefer the layout done in that measurement. More often for the US we use lux but FC has been requested. Either way the difference is easily calculated by:
1FC = 10 Lux
note: 0.0929030436 = 1 Lux to be exact.
Lux definition: A unit of illuminance equal to 1 lumen per square meter.
FC definition: A unit of measurement for the density of light as it reaches a surface. One foot-candle is equal to 1 lumen per square foot.