Workplace Radon Regulation
Royal Decree 1029/2022 and CSN IS-47 Instruction
Complete guide to the obligation to measure radon in workplaces. Learn about deadlines, requirements and how to calculate the number of detectors needed according to current regulations.
Regulatory framework for radon in workplaces
Royal Decree 1029/2022 of December 20 establishes the obligation for occupational activity owners to estimate radon concentration in certain workplaces. This regulation transposes Directive 2013/59/EURATOM and updates the occupational radiological protection framework in Spain.
CSN Instruction IS-47, approved in April 2025, complements the Royal Decree by establishing the official list of priority action municipal terms and technical guidelines for radon measurements in workplaces.
Non-compliance with these obligations may lead to significant sanctions under the Occupational Risk Prevention Law and radiological protection regulations.
Key dates and deadlines
Learn about the most important dates in workplace radon regulations and compliance deadlines.
Publication of RD 1029/2022
Publication of the Royal Decree approving the Regulation on health protection against risks from exposure to ionizing radiation.
Entry into force of RD 1029/2022
The Royal Decree fully enters into force, establishing radon measurement obligations in workplaces.
Approval of IS-47 Instruction
CSN approves the list of priority action municipalities and establishes guidelines for radon measurements.
IS-47 published in BOE
Official publication of IS-47 Instruction in the Official State Gazette, starting the adaptation period.
End of adaptation period
Deadline for workplaces in priority municipalities to start radon measurements (6 months from publication).
Who must measure radon?
RD 1029/2022 establishes the obligation to measure radon for different types of activities and locations.
Underground workplaces
Obligation to measure in all underground workplaces, regardless of geographic location.
- Mines and quarries
- Tunnels and galleries
- Tourist or work caves
- Underground parking with staff
Priority action municipalities
Workplaces on ground floor or below grade located in municipalities included in the CSN IS-47 list.
- Ground floor offices
- Street-level shops
- Hospitality venues
- Educational and health centers
Activities with groundwater
Facilities where groundwater is processed, handled or used.
- Spas and thermal baths
- Bottling plants
- Fish farms
- Thermal installations
Check Your Radon Zone
Search for your municipality to know its radon classification
Detector table by surface area
CSN Safety Guide 11.04 establishes the minimum number of detectors to install according to space type and surface area.
| Space type | Surface area | Detectors |
|---|---|---|
| Compartmentalized offices | Per room | 1 per office |
| Compartmentalized basements | Per section | 1 per room |
| Open-plan spaces | Up to 1,000 m² | 1 per 200 m² |
| Large spaces | 1,000 - 5,000 m² | 1 per 400 m² |
| Very large spaces | Over 5,000 m² | 1 per 500 m² |
| Any space | Under 200 m² | Minimum 2 |
Source: Nuclear Safety Council Safety Guide 11.04
Workplace Detector Calculator
Calculate the number of detectors needed for your workplace according to CSN Safety Guide 11.04.
Calculate required detectorsMeasurement process
Steps to follow to correctly measure radon in your workplace.
Verify obligation
Check if your workplace is in a priority action municipality or is an underground location.
Calculate detectors
Determine the number of detectors needed according to your premises' surface area and characteristics.
Install detectors
Place detectors for a minimum of 2 months (3 recommended), preferably between October and May.
Analyze results
Send detectors to the accredited laboratory and receive the report with results.
Actions based on results
Actions to take depend on the radon concentration measured at your workplace.
Acceptable concentration
< 300 Bq/m³
- No corrective measures required
- Keep the measurement report
- Schedule next measurement according to periodicity
Exceeds reference level
300 - 1,000 Bq/m³
- Report the situation to CSN
- Implement corrective measures
- Perform new verification measurement
- Assess worker dose
High concentration
> 1,000 Bq/m³
- Urgently report to CSN
- Implement immediate corrective measures
- Possible registration as occupational exposure activity
- Worker dosimetric monitoring
Sanctions for non-compliance
Non-compliance with radon measurement obligations in workplaces may lead to administrative sanctions under occupational risk prevention and radiological protection regulations.
Sanction amounts
- Minor infractions€40 - €2,045
- Serious infractions€2,046 - €40,985
- Very serious infractions€40,986 - €819,780
Frequently asked questions
Is my company required to measure radon?
+
You must measure if: 1) Your workplace is in a municipality on the CSN IS-47 list and has premises on ground floor or below grade, 2) You have underground workplaces (mines, tunnels, caves), or 3) You process groundwater. Consult the official CSN list to verify if your municipality is included.
What is the deadline for measurement?
+
The adaptation period ended on November 2, 2025. Affected workplaces must start radon measurements immediately. Measurements must last at least 2 months (3 recommended).
Who can perform the measurements?
+
Measurements must be performed with detectors supplied and analyzed by a laboratory accredited according to UNE-EN ISO/IEC 17025. Radonova is recognized by CSN and meets all requirements.
How many detectors do I need?
+
It depends on the type and size of your premises. In compartmentalized spaces, 1 detector per room. In open-plan spaces, 1 per 200 m² (up to 1,000 m²). Minimum 2 detectors if surface area is under 200 m². Use our calculator for precise calculation.
What if I exceed 300 Bq/m³?
+
You must report the situation to CSN, implement corrective measures (ventilation, sealing, depressurization) and perform a new measurement to verify effectiveness. If exceeding 1,000 Bq/m³, reporting is urgent (1 month) and may require registration as a radiation exposure activity.
How often must measurement be repeated?
+
If the result is below 300 Bq/m³: every 10 years (or 5 if active mitigation systems are in place). If 300 Bq/m³ is exceeded and corrective measures are applied, measurement must be repeated to verify effectiveness.
Are the Canary Islands included in the priority municipalities list?
+
Yes, several municipalities in the Canary Islands are included in the CSN IS-47 list. Check our interactive map or the official CSN list to verify if your municipality is affected.
Need to measure radon at your workplace?
We help you comply with workplace radon regulations. We calculate the required detectors, perform professional installation and manage the entire measurement process.