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ballast-lamp photometric factor

[9.4.9.2.6] The ratio of fluorescent luminaire lumen output using given ballast and lamp types (under photometric test conditions) to the lumen output using the ballast and lamp types used to generate a photometric test report.

Note: This factor is applicable when “energy conserving” lamps and ballasts are used in a luminaire photometered with standard lamps and conventional ballasts; it is also applied in the converse situation.

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