Light intensity test for visual hood

At which locations we should perform light intensity in visual inspection hood.

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12cm height from the wrking station.

Take 5 corners as grid pattern with working height of 12 cm? And calculate the x with correction factor .98

12 cm below working height,? Average of 5 location multiplying by0.98 to find out the fi al result and it should be between 2000-3750 lux. Am I right.

Exactly …visual inspection should be in those limits

What is ment by 0.98

Hi Jehangir,
I too want to know this 0.98 value and request ranjith and manoj to share the reference.
However just to put some valuable information about Lux in pharma I have summarized few quick bites for you all.
Just to understand what is Lux (lx): This is the illuminance produced by a luminous flux of one lumen, uniformly distributed over a surface area of one square metre. One lux is equal to one lumen per square meter.
Luminous Efficacy (lm/W): This is the ratio of luminous flux emitted by a lamp to the power consumed by the lamp. It is a reflection of efficiency of energy conversion from electricity to light form.

So from the above two definitions I presume this 0.98 could be either coeficient of utilization(Cu) (Luminous efficacy) or its a efficiency in Foot Candles.
as from the below Measuring Units of Light Level - Illuminance we come to know that Illuminance is measured in foot candles (ftcd, fc, fcd) or lux (in the metric SI system). A foot candle
is actually one lumen of light density per square foot; one lux is one lumen per square meter.
1 lux = 1 lumen / sq meter = 0.0001 phot = 0.0929 foot candle (ftcd, fcd)
• 1 phot = 1 lumen / sq centimeter = 10000 lumens / sq meter = 10000 lux
1 foot candle (ftcd, fcd) = 1 lumen / sq ft = 10.752 lux

I have given below few reference of Visual inpspection, hope it will help you in understanding the concept of Visual Inspection:

JP 16: 6.06. Foreign Insoluble Matter Test

Thanks sir for Kind details

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According to ranjith we have to check light intensity 12 cm below from light source of visual hood and we have to check intensity at 5 location.pls provide the reference.
I measured intensity at center it was 10000 lux which is out of limit.

Its very much…don’t your visual inspectors get strain on eyes due to such a bright light.
Please re-verify your requirements w.r.t. tube-light with required lumens and calibration of lumen tester.

Is this visual hood used during online visual inspection activity or offline visual inspection activity?

Thanks for your brieifing

Can you please explain the calculation elaborately

U have to take intensity near about 3 inches away from the tubelight for visual inspection hood ,multiple times upto 10 times and take avg of that as your intensity of that tubelight

measure it into white background at the center 3inches away from tubelight

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Any reference