S‑phrases (safety phrases) — standardized precautionary instructions for chemicals
S‑phrases are short, standard safety instructions used in European chemical labelling to advise on storage, handling, first aid, disposal and environmental precautions; historically used with R‑phrases.
Overview
S‑phrases, or safety phrases, are concise, standardized instructions intended to communicate important precautions for the safe use, storage and disposal of chemical substances and preparations. They were developed as part of an integrated European system for classification and labelling of dangerous substances, where they were commonly paired with R‑phrases (risk phrases). S‑phrases cover a range of practical measures such as avoiding particular exposures, steps to take in case of accidents, and requirements for personal protective equipment or special storage. While the international Globally Harmonized System (GHS) and the European CLP Regulation have largely superseded the R/S system in regulatory practice, S‑phrases remain important for historical labelling, older safety data sheets and educational contexts.
Characteristics and organization
The S‑phrases are short, numbered sentences that are easy to print on labels and to include in safety data sheets. Each phrase is identified by an "S" followed by a number (for example, S1, S2). Some phrases allow the manufacturer or supplier to insert specific details (for example, the appropriate liquid, inert gas, incompatible materials or temperature limits). The content of the phrases can be grouped broadly into categories:
- Storage and containment (e.g., S1, S7, S8, S49)
- Handling precautions and avoidance of exposure (e.g., S20, S21, S22, S24, S25)
- First aid and emergency measures (e.g., S26, S27, S45, S46, S62)
- Fire and explosion advice (e.g., S16, S17, S33, S41, S43)
- Personal protective equipment (e.g., S36–S39)
- Environmental and disposal instructions (e.g., S29, S35, S56–S61)
Complete list of S‑phrases
The following list reproduces the conventional S‑phrases used in the traditional European labelling system. Where the original wording required additional specification by the manufacturer, the brackets indicate that the supplier should supply the missing information.
- S1: Keep locked up
- S2: Keep out of the reach of children
- S3: Keep in a cool place
- S4: Keep away from living quarters
- S5: Keep contents under ... (appropriate liquid to be specified by the manufacturer)
- S6: Keep under ... (inert gas to be specified by the manufacturer)
- S7: Keep container tightly closed
- S8: Keep container dry
- S9: Keep container in a well-ventilated place
- S10: Keep contents wet
- S11: Avoid contact with air
- S12: Do not keep the container sealed
- S13: Keep away from food, drink and animal foodstuffs
- S14: Keep away from ... (incompatible materials to be indicated by the manufacturer)
- S15: Keep away from heat
- S16: Keep away from sources of ignition - No smoking
- S17: Keep away from combustible material
- S18: Handle and open container with care
- S20: When using do not eat or drink
- S21: When using do not smoke
- S22: Do not breathe dust
- S23: Do not breathe gas/fumes/vapour/spray (appropriate wording to be specified by the manufacturer)
- S24: Avoid contact with skin
- S25: Avoid contact with eyes
- S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice
- S27: Take off immediately all contaminated clothing
- S28: After contact with skin, wash immediately with plenty of ... (to be specified by the manufacturer)
- S29: Do not empty into drains
- S30: Never add water to this product
- S33: Take precautionary measures against static discharges
- S35: This material and its container must be disposed of in a safe way
- S36: Wear suitable protective clothing
- S37: Wear suitable gloves
- S38: In case of insufficient ventilation wear suitable respiratory equipment
- S39: Wear eye/face protection
- S40: To clean the floor and all objects contaminated by this material use ... (to be specified by the manufacturer)
- S41: In case of fire and/or explosion do not breathe fumes
- S42: During fumigation/spraying wear suitable respiratory equipment (appropriate wording to be specified by the manufacturer)
- S43: In case of fire use ... (indicate in the space the precise type of fire-fighting equipment. If water increases the risk add - Never use water)
- S45: In case of accident or if you feel unwell seek medical advice immediately (show the label where possible)
- S46: If swallowed, seek medical advice immediately and show this container or label
- S47: Keep at temperature not exceeding ... °C (to be specified by the manufacturer)
- S48: Keep wet with ... (appropriate material to be specified by the manufacturer)
- S49: Keep only in the original container
- S50: Do not mix with ... (to be specified by the manufacturer)
- S51: Use only in well-ventilated areas
- S52: Not recommended for interior use on large surface areas
- S53: Avoid exposure - obtain special instructions before use
- S56: Dispose of this material and its container at hazardous or special waste collection point
- S57: Use appropriate containment to avoid environmental contamination
- S59: Refer to manufacturer/supplier for information on recovery/recycling
- S60: This material and its container must be disposed of as hazardous waste
- S61: Avoid release to the environment. Refer to special instructions/safety data sheet
- S62: If swallowed, do not induce vomiting: seek medical advice immediately and show this container or label
- S63: In case of accident by inhalation: remove casualty to fresh air and keep at rest
- S64: If swallowed, rinse mouth with water (only if the person is conscious)
History and regulatory status
S‑phrases were standardized during the latter half of the 20th century to create a consistent, concise method of advising users about chemical hazards across languages and national borders within Europe. They formed part of the traditional labelling regime used in the European Union and related jurisdictions, applied on product labels, in technical bulletins and on safety data sheets. Over time, international efforts to harmonize chemical classification resulted in the adoption of the UN Globally Harmonized System (GHS) and, in the EU, its implementation through the CLP Regulation. These newer systems use precautionary statements with different numbering and wording, so modern labels increasingly employ GHS/CLP statements. Nonetheless, older products, archival documents and educational materials still refer to S‑phrases.
Practical significance and distinctions
Understanding S‑phrases is useful for reading legacy safety information, translating older chemical documentation and maintaining continuity in workplaces that handle historic stocks. The phrases are intentionally brief and prescriptive; where more detail is required the manufacturer or supplier could insert specifics within the phrase (for instance, naming a particular liquid to keep contents under or a temperature limit). When comparing S‑phrases to modern precautionary statements under GHS/CLP, note that both aim to communicate the same kinds of protective measures but differ in numbering, exact wording and legal framework.
For safe practice, users should consult current safety data sheets and follow the most recent regulatory guidance applicable in their jurisdiction. If an older label uses S‑phrases, those instructions remain practical guidance, but they should be read alongside up-to-date hazard classifications and emergency procedures.
Questions and answers
Q: What should be done to keep the contents of a container locked up?
A: S1 states that the contents of a container should be kept locked up.
Q: How can children be prevented from accessing the contents of a container?
A: S2 states that the contents of a container should be kept out of the reach of children.
Q: Where should containers with their contents be stored?
A: S3 recommends keeping containers in a cool place, while S4 suggests keeping them away from living quarters.
Q: What liquid is recommended by manufacturers for storing certain materials?
A: S5 suggests using an appropriate liquid as specified by the manufacturer for storing certain materials.
Q: What gas is recommended by manufacturers for storing certain materials?
A: S6 recommends using an inert gas as specified by the manufacturer for storing certain materials.
Q: What precautions are suggested when handling and opening containers?
A: S18 advises to handle and open containers with care.
Q: What safety measures are recommended when using this material or its container?
A:S20-22 suggest not eating, drinking or smoking while using this material or its container, and not breathing dust or gas/fumes/vapour/spray (as appropriate). Additionally, S24-27 recommend avoiding contact with skin and eyes, taking off contaminated clothing immediately after contact with skin, and seeking medical advice if necessary.
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Author
AlegsaOnline.com S‑phrases (safety phrases) — standardized precautionary instructions for chemicals Leandro Alegsa
URL: https://en.alegsaonline.com/art/125113