Risk and Safety Statements (R‑ and S‑phrases)

Format and typical examples

Each statement is identified by a letter and number: R followed by a number gives the specific risk (for example R34 indicates "causes burns"). S followed by a number gives a safety recommendation (for example S36 means "wear suitable protective clothing"). Combinations are common (e.g., S24/25 to avoid contact with skin and eyes).

• Example risk phrases: R22 (harmful if swallowed), R34 (causes burns), R50 (very toxic to aquatic organisms).
• Example safety phrases: S1 (keep locked up), S2 (keep out of the reach of children), S36 (wear protective clothing), S24/25 (avoid contact with skin and eyes).

History and regulatory context

The R/S system originated in European chemical legislation and became familiar through EU directives and national implementations. In the late 2000s a new global system, the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), was adopted and many jurisdictions revised their rules. Under these newer frameworks, R/S phrases have largely been superseded by hazard (H) statements and precautionary (P) statements, though older labels and documents may still bear R/S codes.

Uses and limitations

R and S phrases were designed for quick reference on labels and in safety data sheets to support safe handling, storage and transport. They are brief by design, so they do not replace full safety data sheets, workplace procedures or professional risk assessments. Because numbering and wording were standardized, they made translation and pictogram use easier, but they could be misinterpreted if taken out of context or used without complementary information.

Practical guidance and further information

When you encounter R/S phrases, read them together with full product documentation and follow local regulations and workplace rules. For current classification and labeling guidance consult authoritative sources or regulatory portals; for more background see additional guidance on hazard communication.