The Precautionary Principle states that when an activity raises threats of harm to health, precautionary measures should be taken even if cause-and-effect relationships are not fully established.
When to Apply Precaution
The principle is most relevant when there is potential for severe or irreversible consequences combined with scientific uncertainty. EMR meets both conditions: potential for cancer, neurological damage, and reproductive issues; plus lack of long-term epidemiological data.
Risk vs. Uncertainty
Risk applies when probability and consequences are known. Uncertainty applies when they're unknown. The precautionary principle is designed for uncertainty—shifting burden of proof to technology proponents.
Policy Applications
- Setting exposure limits lower than thermal-only thresholds
- Implementing ALARA (As Low As Reasonably Achievable)
- Promoting wired technologies in schools and sensitive environments
- Public education on reducing personal exposure