# Reference level vs basic restriction

> ICNIRP's two-tier structure: basic restrictions are the dosimetric limits that matter biologically; reference levels are the externally measurable proxies derived from them.

- Canonical URL: https://emfbase.com/glossary/reference-level
- Collection: Glossary
- Record id: `glossary:reference-level`
- Status: verified
- Last verified: 2026-08-12
- JSON: https://emfbase.com/api/glossary/reference-level

## Key values

- **Category:** regulation

## Definition

A basic restriction limits an internal quantity such as SAR or induced electric field, which cannot be measured in a living person. A reference level limits an external quantity such as power density or magnetic flux density, and is derived conservatively so that compliance with it guarantees compliance with the basic restriction. Exceeding a reference level is therefore not automatically a breach of the basic restriction — it triggers a more detailed assessment.

## Sources

- `icnirp-2020` International Commission on Non-Ionizing Radiation Protection (2020). *Guidelines for Limiting Exposure to Electromagnetic Fields (100 kHz to 300 GHz)*. https://www.icnirp.org/en/publications/article/rf-guidelines-2020.html — guideline, link checked 2026-08-12

Data licence: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Dataset version 2026.08.1. Retrieved from EMFBase, https://emfbase.com.

This record is reference data, not medical or legal advice. Regulatory limits, scientific guidelines and precautionary values are labelled separately and answer different questions.