Last reviewed: Sep 15, 2026
Lighting data arrives in several formats with different purposes, and buyers who cannot tell them apart end up specifying from a marketing sheet. The three that matter each answer a different question.
The three documents
A photometric test report measures what the product actually emits. A lumen maintenance projection estimates how output falls over time. An electronic photometric file describes the distribution of light in a format software can use.
| Document | Answers | Typical use |
|---|---|---|
| Photometric test report | Output, colour, distribution at the time of test | Verifying a claim on a data sheet |
| Lumen maintenance projection | How output behaves over thousands of hours | Warranty and lifecycle planning |
| Photometric data file | The three-dimensional distribution | Layout design in lighting software |
| Safety test report | Electrical construction and temperature rise | Compliance, not light quality |
A marketing data sheet is not a test report
Values on a product page are frequently derived, rounded or carried over from a previous version. When a specification matters, ask for the report and check the model number, the date and the laboratory on it, because a report for a different model is a common and expensive mix-up.
Distribution is the missing document
Output tells you how much light exists. Distribution tells you where it goes, and for task lighting the second is worth more than the first. A lamp with lower output and a well-designed asymmetric distribution will outperform a brighter symmetrical one at the same distance.
What to ask a supplier for, in order
Three requests, each of which a competent manufacturer can answer:
- The photometric report for the exact model, including the colour data
- The distribution description, or the data file if the specification is competitive
- The lumen maintenance basis for the warranty period, with the test method named
Use it to compare, not to decorate
The value of photometric data is in comparing two products on the same basis. A report attached to a quotation and never used is a document; the same report used to disqualify an over-claimed alternative is a purchasing tool.
Related reading
Frequently asked questions
What is a photometric report?
It is the measured light output, distribution and colour data for a luminaire, used to verify it meets a spec. Request it for any high-value or contract order.
Which numbers matter on a spec sheet?
Lumens (output), colour temperature (Kelvin), CRI (colour accuracy), and the beam or distribution shape. Match these to the room's target, not just the wattage.
How do I confirm a lamp meets my spec?
Compare the photometric report and the listing (ETL or UL to UL 153; CSA C22.2 for Canada) against your written requirement before approval.
Sourcing lamps for your business?
We stock the Anrotix range in the United States — complete with LED bulbs and accessories — and supply from 10 units, mixed across SKUs.
Request wholesale pricingRelated product: 30W LED torchiere — ask for the photometric file for this model before you specify it
Recruiting regional partners worldwide — help@anrotix.cn