# How do you measure foot candles?

## How do you measure foot candles?

Multiply the Length times the Width of the Room to get the Room Square Footage. For example, if the room is 10 feet wide and 10 feet long, the Room Square Footage will be 100 square feet. A foot-candle is how bright the light is one foot away from the source.

### How many watts is a foot-candle?

Foot-candle to Watt/sq. Cm (at 555 Nm) Conversion Table

Foot-candle [ft*c, Fc] Watt/sq. Cm (at 555 Nm)
1 ft*c, fc 1.5759751708199E-6 watt/sq. cm (at 555 nm)
2 ft*c, fc 3.1519503416398E-6 watt/sq. cm (at 555 nm)
3 ft*c, fc 4.7279255124597E-6 watt/sq. cm (at 555 nm)
5 ft*c, fc 7.8798758540995E-6 watt/sq. cm (at 555 nm)

How many foot candles are in a 100 watt bulb?

Their efficiency is in the range of 4 lumens per watt. This means that a 100 watt bulb will generate 400 lumens – TOTAL. (Here’s the big leap) Now, if we COULD reflect all of that 400 lumens onto 1 square foot we would get a light intensity of 400 foot candles.

How many candlepower is a 60 watt bulb?

Your average 60 watt household light bulb produces 650 to 700 lumens when burned under standardized conditions. Therefore you can estimate that a 60 watt household light bulb, burned under average household conditions might produce somewhere between 50 and 55 candle power, give or take…

## What is the definition of a foot candle?

A foot-candle is the amount of light generated by a single candle that falls on a single square foot of surface no more than a foot away from the candle. While the term continues to be used in OSHA’s standards, lighting professionals consider it out of date, and it has generally been replaced by more precise terms, such as lumen and lux.

### How are foot candles related to lumen output?

Well rather than measuring the amount of light that leaves a light source (lumen output), foot-candle measurements focus on the amount of light that reaches a surface area. For example, a foot-candle relates to the amount of light that is on the ground surface beneath a parking lot light as opposed to the output of the parking lot light.

How big is a foot candle on a light meter?

Most light meters will output their readings in foot-candles or “lux” (the SI-derived unit which is similar to foot-candles but measures a one-meter square rather than a one-foot square). If you do get a light meter that renders its measurements in lux, and you really need them in foot-candles, just remember this number: 10.764.

Why do we still use the word candle to measure light?

Foot-candle is the most widespread lighting measurement in the industry. Why do we still use the word “candle” to measure light in this day and age? The explanation for this choice dates back to the origins of the candle itself.