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For European workplace projects where EN 12464-1 applies, writing, typing, reading and data processing have a required maintained illuminance of 500 lx.
EN 12464-1, ANSI/IES RP-1-24 and WELL do not serve the same purpose and should not be treated as three interchangeable lux standards.
Office projects may reference all three when reading office lighting design standards, but they are not the same type of document.
- EN 12464-1 is an indoor workplace lighting standard.
- ANSI/IES RP-1-24 is the IES Recommended Practice for lighting office spaces.
- DOBRZE is a health and wellbeing certification framework; its Light concept includes Visual Lighting Design, Circadian Lighting Design, glare control and related features.
The practical question is therefore not “Which standard is best?”
It is: which document applies to this project, what does it require, and what still needs to be checked beyond a single lux value?
If you are still choosing fixture families for the ceiling plan, start with What Are the Best Lights for an Office?. For how light relates to people beyond visual task lighting, see What Is Human-Centric Lighting?.
W skrócie: Use EN 12464-1:2021 Table 34 for European workplace task values—500 lx is the required maintained illuminance for writing, typing, reading and data processing, not a one-number office rule. Treat ANSI/IES RP-1-24 as a separate Recommended Practice. Treat WELL as a certification framework that sits beside normal project lighting requirements.
Spis treści
- Office illuminance at a glance
- What EN 12464-1 actually covers
- What ANSI/IES RP-1-24 covers
- EN and IES are not the same standard
- Is EN 12464-1 mandatory?
- Where WELL fits
- Why 500 lux is not a complete specification
- What each framework asks you to think about
- How to check an office lighting design
- Typowe błędy
- What a specification should record
- Which one should a project use?
- Wniosek
- Streszczenie
- Często zadawane pytania
📊 Office Illuminance at a Glance
EN 12464-1:2021 — Table 34 Offices
| Task / activity | Required maintained illuminance | UGRL | Uo | Ra |
|---|---|---|---|---|
| Filing, copying, etc. | 300 lx | 19 | 0.40 | 80 |
| Writing, typing, reading, data processing | 500 lx | 19 | 0.60 | 80 |
| Technical drawing | 750 lx | 16 | 0.70 | 80 |
| CAD work stations | 500 lx | 19 | 0.60 | 80 |
| Conference and meeting rooms | 500 lx | 19 | 0.60 | 80 |
| Reception desk | 300 lx | 22 | 0.60 | 80 |
| Archiving | 200 lx | 25 | 0.40 | 80 |
These are the required minimum maintained illuminance values in EN 12464-1:2021 Table 34.
The same table also contains modified illuminance values for common context modifiers, together with cylindrical, wall and ceiling illuminance requirements.
The figures above apply to specific tasks and activities.
They do not mean every part of every office should be designed to one identical lux level.
Conference and meeting rooms share the 500 lx required value in this table.
How to measure faces, displays and walls for video call rooms is a separate check, covered in our conference-room brightness guide.
🎯 Is 500 lx the only office number in EN?
No. Table 34 assigns different required maintained illuminance values by task, from archiving at 200 lx to technical drawing at 750 lx.
📘 What Does EN 12464-1 Actually Cover?
EN 12464-1 is not simply a table saying “office = 500 lux.”
EN 12464-1 office lighting requirements are set by space, then by task or activity, then by the visual criteria that belong to that row.
Maintained illuminance
Maintained illuminance is the level the lighting installation is designed to maintain over its operating period.
It is not simply the reading taken when a brand-new installation is first switched on.
This article explains the concept only.
It does not walk through maintenance-factor calculations.
EN includes more than lux
EN 12464-1:2021 Table 34 covers more than one horizontal illuminance cell.
The same task rows also address:
- required illuminance
- modified illuminance
- uniformity Uo
- colour rendering Ra
- glare limit RUGL
- cylindrical illuminance
- wall illuminance
- ceiling illuminance
- specific requirements where listed
A compliant office-lighting specification therefore needs more than one horizontal illuminance value.
What does “modified illuminance” mean?
Table 34 separates:
- required = the minimum value
- modified = a higher value that considers common context modifiers
Examples from the same office table:
- Filing / copying: 300 → 500 lx
- Writing / typing / reading / data processing: 500 → 1000 lx
The modified value is not the normal target for every office.
It is the higher step the standard associates with context modifiers.
It should not be rewritten as “office lighting should be 1000 lx.”
🎯 Does EN 12464-1 say every office needs 500 lx?
No. Requirements are assigned by task or activity, and the table also includes uniformity, glare and colour rendering.
📗 What Does ANSI/IES RP-1-24 Cover?
The full title is ANSI/IES RP-1-24 — Recommended Practice: Lighting Office Spaces.
The current IES store listing shows a 2024 edition and document type Recommended Practice.
It addresses lighting for offices and related areas.
Public product copy points to updates on visual glare mitigation, visual displays, control systems used in offices, and acoustic luminaires, among other office design topics.
That is enough to place the document correctly in a project conversation.
It is not enough to republish Annex A numbers here.
Why we should not copy EN numbers into the IES column
EN and IES are separate lighting frameworks.
Converting 500 lx into foot-candles does not turn an EN requirement into an IES recommendation.
This page does nie build an IES-versus-EN numerical comparison table.
Reason: the IES public store page shows that RP-1-24 includes illuminance recommendations, but the full Annex A values are not freely reproduced for republication here.
Do not fill that gap from RP-1-12, RP-1-20, RP-1-22 or vendor blogs and then label the result as RP-1-24.
When a US brief asks for IES office lighting recommended levels, name the adopted edition first.
Then use the published practice itself—not an EN row converted into foot-candles.
🎯 Should a US project automatically use EN 12464-1 values?
No. Check the applicable code, project specification and adopted lighting references for that project.
🔀 EN 12464-1 and IES RP-1 Are Not the Same Standard in Different Units
| EN 12464-1:2021 | ANSI/IES RP-1-24 | |
|---|---|---|
| Primary scope | Indoor workplaces | Offices and related areas |
| Current edition discussed here | 2021 | 2024 |
| Illuminance guidance | Tak | Tak |
| Blask | Tak | Tak |
| Colour / lighting quality | Tak | Tak |
| Office-specific considerations | Tak | Tak |
| Same numerical framework | Do not assume | Do not assume |
| Document type | European Standard | Recommended Practice |
Both frameworks discuss similar design questions.
Similar metric ≠ identical requirement.
This article does not rank which document is “stricter.”
That comparison needs matching conditions, matching editions and matching project rules—which is not the search task here.
🎯 Can you convert EN lux into IES recommendations?
No. Unit conversion changes the unit, not the source document or the requirement set.
⚖️ Is EN 12464-1 Mandatory?
An EN standard should not automatically be described as legally mandatory in every European project.
CEN-CENELEC states that European Standards are voluntary and that there is no legal obligation to apply them simply because they exist.
At the same time, each EN is implemented as a national standard by CEN members, and national legislation, contracts or project specifications can require a named standard.
So the accurate project answer is:
Whether EN 12464-1 is mandatory for a specific project depends on national legislation, contractual requirements and the project specification.
Do not write “EN 12464-1 is mandatory in Europe.”
Do not write “EN 12464-1 is optional” as if no project can ever be bound to it.
🎯 Is EN 12464-1 a Europe-wide legal code?
No. The standard itself is voluntary; laws and contracts may still require it on a given project.
🏥 Where Does WELL Fit Into Office Lighting Standards?
WELL is not simply a third office illuminance standard alongside EN and IES.
WELL is a broader health-building certification framework.
Its Light concept includes features such as light exposure, L02 Visual Lighting Design, L03 Circadian Lighting Design, electric light glare control, and daylight / visual-balance / occupant-control topics depending on the project pathway.
That is why WELL building standard lighting sits beside ordinary design references rather than replacing them.
L02 Visual Lighting Design
L02 is about visual lighting design for acuity and related visual conditions.
Current WELL practice allows more than one compliance logic.
In plain project language:
WELL L02 can use a recognised lighting-reference-guideline pathway or a predetermined-light-level pathway.
It therefore interacts with conventional lighting standards rather than simply replacing them.
This page does not republish a full predetermined light-level table.
If WELL is on the project, read the selected feature text and verification method for that certification path.
L03 Circadian Lighting Design is a different question
L03 deals with circadian lighting rather than conventional horizontal task illuminance alone.
It is a dedicated feature, not another name for the EN 500 lx desk row.
This article stops at that positioning.
EML / m-EDI targets, exposure duration, measurement position and scoring belong in a separate WELL lighting feature review.
WELL does not replace project lighting requirements
A workable order looks like this:
- Local regulation and the project specification
- EN, IES or other design references adopted for the job
- If the project pursues WELL, the applicable Light features on top
Do not draw the choice as EN Lub IES Lub WELL.
WELL may sit alongside the project’s normal lighting-design requirements.
🎯 Is WELL just another office lux table?
No. WELL is a health-building certification framework; its Light features sit beside ordinary project lighting references.
💡 Why 500 Lux Is Not a Complete Office Lighting Specification
“500 lx” is a useful office task-lighting reference, but it is not a complete office-lighting specification.
Take the most common desk row in EN Table 34: writing, typing, reading and data processing.
The same row does not stop at horizontal illuminance.
It also carries:
- Uo 0.60
- Ra 80
- RUGL 19
- cylindrical illuminance 150 lx
- wall illuminance 150 lx
- ceiling illuminance 100 lx
- required 500 lx
- modified 1000 lx
So a design review still has to answer:
- Where was the 500 lx calculated or measured?
- Is it a maintained value?
- Is uniformity sufficient?
- Is glare controlled?
- What colour-rendering requirement applies?
- Do room and vertical surfaces meet the listed criteria where applicable?
Those questions matter more than repeating “offices need 500 lux.”
They also matter when you set office illuminance levels for mixed-task floors.
🎯 Is 500 lx enough to choose an office lighting design?
No. Treat it as one task-row value, then check uniformity, glare, colour rendering and room or vertical lighting where the reference requires them.
🧭 What Does Each Framework Ask the Project Team to Think About?
| Design question | EN 12464-1 | IES RP-1-24 | DOBRZE |
|---|---|---|---|
| Task illuminance | ✓ | ✓ | ✓ through the applicable L02 pathway |
| Blask | ✓ | ✓ | ✓ |
| Colour / visual quality | ✓ | ✓ | ✓ |
| Lighting quality beyond lux | ✓ | ✓ | ✓ |
| Circadian-specific feature | Not the role of one office lux row | Not compared here | Dedicated L03 |
| Health-building certification | — | — | ✓ |
Do not summarise WELL as “daylight and circadian only.”
The Light concept also covers visual lighting, glare, daylight and related occupant-control topics.
🎯 Are EN, IES and WELL answering the same question?
No. They overlap on visual quality themes, but WELL adds certification features that sit beside normal design references.
✅ A Practical Way to Check an Office Lighting Design
Step 1 — Check the project jurisdiction and specification
Start with:
- country / region
- building code
- client specification
- consultant requirements
- certification target
Do not pick EN or IES first and then force the project into that choice.
Step 2 — Check the exact document and edition
Write the reference as, for example:
- EN 12464-1:2021
- ANSI/IES RP-1-24
“According to IES” is not specific enough.
Editions change, and Annex content changes with them.
Step 3 — Identify the actual task or activity
One office floor may include:
- desk work
- filing / copying
- CAD
- reception
- meeting
- archiving
Standards start from task / activity.
They do not start from “this is an office, so everything is 500 lx.”
Step 4 — Check the required illuminance
For EN projects, match Table 34 to the task.
Przykłady:
- desk / data-processing work → 500 lx
- filing / copying → 300 lx
- technical drawing → 750 lx
- reception desk → 300 lx
- archiving → 200 lx
Conference-room measurement for faces, displays and cameras is a separate procedure.
Do not collapse that procedure into this standards overview.
Step 5 — Check more than lux
Also review:
- jednolitość
- blask
- colour rendering
- cylindrical / vertical lighting where applicable
- wall / ceiling lighting where applicable
- any listed specific requirements
This is usually where a one-line “500 lx design” falls short.
Step 6 — If WELL is required, check applicable WELL features separately
At minimum, check:
- L02 Visual Lighting Design
- L03 Circadian Lighting Design, if the project selected it
- glare, daylight or other selected Light features
Do not conclude that WELL lighting is satisfied because a desk calculation hit 500 lx.
Step 7 — Record the basis of design
The design file should show:
reference document + edition + task/space + metric + required value
Not a vague line such as “Lighting complies with international standards.”
When the layout calls for continuous runs or recessed ambient, compare LED linear lights against the ceiling and glare criteria—not against a single lux slogan.
🎯 What is the first check on an office lighting package?
Check jurisdiction, the named document edition and the actual task rows before arguing about any one lux number.
⚠️ Common Mistakes When Reading Office Lighting Standards
Treating 500 lx as the whole office specification
It is one task-row indicator, not the full package.Applying the same number to every office area
Reception, archiving and technical drawing use different EN Table 34 values.Writing UGR 19 as the universal office limit
In Table 34, desk work uses 19, technical drawing 16, reception 22 and archiving 25.Treating the modified EN value as the normal target
500 → 1000 lx does not mean every office should be designed to 1000 lx.Copying EN values into an “IES” table
Unit conversion does not change the data source.Calling IES RP-1-24 a mandatory US code
IES lists it as a Recommended Practice.Calling EN 12464-1 universally mandatory
Project obligation depends on national rules and contract adoption.Treating WELL as a replacement for EN or IES
WELL has its own certification structure, and L02 itself has more than one compliance pathway.
🎯 What is the most common standards reading error?
Treating one desk lux number as if it already covered glare, uniformity, colour rendering and certification features.
📋 What Should an Office Lighting Specification Record?
| Przedmiot | What should be recorded |
|---|---|
| Reference | Exact standard / guideline |
| Edition | Year / revision |
| Przestrzeń | Office, reception, meeting room, etc. |
| Task / activity | What people actually do there |
| Maintained illuminance | Required project value |
| Jednolitość | Applicable Uo |
| Blask | Applicable glare criterion |
| Colour rendering | Applicable Ra / project CRI |
| Room / vertical lighting | Where applicable |
| Sterownica | Required function |
| How checked | Calculation and/or measurement method |
A specification is much easier to check when every numerical requirement has a named source and edition.
Where discrete ambient points carry the visual task, check Oświetlenia LED against distribution and glare limits after the reference row is fixed.
🎯 What makes an office lighting specification easy to check?
Every number should point to a named document, edition, space and task—not to a vague “international standards” claim.
🏁 EN, IES or WELL: Which One Should a Project Use?
| Project situation | Starting point |
|---|---|
| European workplace project | Applicable national/project requirements and the relevant EN-based standard |
| US office project | Applicable code + project specification + current IES guidance where adopted/referenced |
| WELL project | Normal project lighting requirements plus applicable WELL features |
| International project | Local requirements + contract specification + explicitly agreed lighting reference |
The project location, applicable regulation and contract determine what must be followed.
No single document in this article becomes a universal global requirement.
A lighting package that quotes one lux number but omits the edition, task row and glare criterion is difficult to check.
🎯 Which document wins for every office worldwide?
None. Jurisdiction, contract and certification target decide the starting reference set.
🏁 Conclusion: Which Office Lighting Standard Should You Follow?
EN 12464-1, ANSI/IES RP-1-24 and WELL should not be treated as three competing versions of the same office-lighting standard.
EN sets workplace task and activity lighting criteria.
IES RP-1 is an office-specific Recommended Practice.
WELL is a health and wellbeing certification framework with separate Light features.
Good office lighting design begins with the right document, the right edition and the right visual task—not with copying one lux number across every room.
Explore our related blog posts:
- Wybór temperatury barwowej oświetlenia LED dla różnych obszarów komercyjnych
- Why Suspended Linear Lighting Differs in Offices and Lobbies
- How to Choose Modern Linear Lighting for Offices and Retail in 4 Steps
📌 Summary
- EN 12464-1:2021 gives 500 lx required maintained illuminance for writing, typing, reading and data processing, but different office tasks have different values.
- The same EN table also addresses uniformity, glare, colour rendering and room/vertical lighting.
- ANSI/IES RP-1-24 is the current IES Recommended Practice for office spaces; do not substitute EN values for its Annex A recommendations.
- WELL is a health-building certification framework, not simply another office lux table.
- Always check jurisdiction, document edition, task/activity and the exact source of every project value.
Często zadawane pytania
Notatki i źródła
- EN 12464-1:2021 Table 34 Offices — task-row values for filing/copying, writing/typing/reading/data processing, technical drawing, CAD, conference/meeting, reception and archiving; required vs modified illuminance; Uo, Ra, RUGL; writing/typing row cylindrical/wall/ceiling values as listed above (paid standard; values from project table excerpt).
- ANSI/IES RP-1-24 — IES Webstore product listing for Recommended Practice: Lighting Office Spaces; document type Recommended Practice; 2024 edition; office-space scope. Annex A numerical recommendations not reproduced here.
- CEN-CENELEC — European Standards are voluntary; use of standards is voluntary; ENs are implemented as national standards by members (european-standardization overview).
- WELL v2 — Feature L02 Visual Lighting Design: IWBI states two compliance pathways for appropriate work-plane illuminance—selected lighting reference guidelines or predetermined light levels; Feature L03 is Circadian Lighting Design (WELL Light Features education materials documenting L02 / L03 / L04; Light concept hub: standard.wellcertified.com/light). Predetermined lux tables and L03 EML targets are not reproduced in this article.
Planning an Office Lighting Project?
XHLUX provides commercial office lighting options, including linear lighting and downlights, for projects with different illuminance, glare-control, colour-rendering and control requirements.
