How to write a good safety data sheet

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Contents: [Formatting] [Completeness] [Technical compliance: classification, consistency, specificity, tailoring to product and user] [National adaptation: language and translation, occupational exposure limits, national legislation, poison centres] [ext-SDS] [Conclusions] [References]

Too often, suppliers see SDS provision as a legal compliance issue, rather than as a communication tool

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Despite three decades of EU legislation and guidance, monitoring and enforcement, safety data sheets (SDSs) have a reputation for poor quality.

Extended safety data sheets (ext-SDSs), with exposure scenarios attached as an Annex, have a reputation for being most useful as a doorstop.

Prior to the REACH Regulation (1907/2006), there was often a lack of hazard information on substances, but there is now little excuse for chemical suppliers not providing useful data to keep workers safe when handling their products.

Too often, suppliers see SDS provision as a legal compliance issue, rather than as a communication tool and an important part of product stewardship. This problem is exacerbated by inspections and enforcement, where authorities focus on formatting and completeness of SDSs, and not utility or accuracy of the data.

This article covers the main facets of GB and EU SDSs that require attention during compilation to give not only a compliant SDS that will pass inspection, but also prove useful.

For details of the SDS formatting and content, see our useful SDS content guide. For help with the jargon, check our glossary.

If you wish to find out more about our services for safety data sheets, see our services page or contact us.


A quick scan of an SDS will quickly reveal whether it includes the correct headings

Recipients of an SDS and inspectors are likely to check an SDS by first looking at its formatting.

Most countries, including the EU and UK, have SDS formatting based on the UN’s Globally Harmonised System (GHS), which is an international template giving the 16 Sections under which the product information is organised.

However, UK and EU REACH Regulations are much more prescriptive of the formatting, and include additional mandatory sub-headings.

A quick scan of an SDS will quickly reveal whether it includes the correct headings as mandated in GB and EU legislation, and therefore likely to be compliant in more important areas.

Many compilers like to put the legal citation of the formatting Regulation for the SDS, such as ‘compiled according to Regulation 2020/878‘, to demonstrate that it is intended for the EU or UK market. This is not a mandatory requirement.

Some of the EU national enforcement agencies are strict about adherence to the mandatory headings and sub-headings as they are laid out in the legislation, and will penalise suppliers for even minor deviations, such as not using the word ‘SECTION’ in the Section header.

Officially, GB SDSs should conform to the older formatting requirements of EU Regulation 2015/830, as UK REACH has not been updated with the new Regulation 2020/878 required for new EU SDSs. The UK is expected not to penalise SDSs that conform to the newer EU standard.

Formatting checklist:

  • Check the SDS against the mandated headings and sub-headings in Regulation 2020/878. In the EU, the older format given in Regulation 2015/830 can be used in GB, or in the EU up until 31 December 2022.


If no-one is in full compliance, then compilers may settle for an industry standard level of failure.

The SDS legislation contains a few statements that force the compiler to add text even when there is no relevant information available. Key requirements are:

  • General: The safety data sheet shall not contain blank subsections.
  • Section 9 (physical and chemical properties): All relevant information on the substance or mixture shall be provided. The method of determination shall be provided. If a particular property does not apply, or if no information is available, this shall be clearly indicated with reasons
  • Section 11 (toxicological information): Information shall be provided for each hazard class (eg acute toxicity, irritation, carcinogenicity). If the product is not classified for a particular hazard class, the compiler should state the reason (eg lack of data, technical impossibility to obtain the data, inconclusive data, or data which are conclusive although insufficient for classification). In the latter case the compiler includes the statement ‘based on available data, the classification criteria are not met.’
  • Section 11: For a mixture SDS, the data should describe the toxicological properties of the mixture and relevant hazardous components.
  • Section 11: Information shall be provided on the effects of the substance or mixture via ingestion (swallowing), inhalation or skin/eye exposure.
  • Section 12 (ecological information): Information on toxicity shall be provided when available. Where experimental data are not available, the supplier shall consider whether reliable and relevant information obtained from models can be provided. For mixtures, persistence, bioaccumulation potential and mobility in soil shall be given for each individual relevant substance in the mixture.

With this long and complicated list of requirements, it is difficult to foresee a case where the authorities would not be able to find some infringement of the SDS legislation, especially where the SDS is generated by software.

Perhaps one reason for the poor quality of SDSs is that the bar is set at an unrealistically high level. If no-one is in full compliance, then compilers may settle for an industry standard level of failure.

Completeness checklist:

  • Make sure all sub-sections of the SDS are populated
  • Use REACH registration data available from ECHA website
  • Indicate test methods
  • Use modelling or expert judgement if it is applicable
  • Give reasons for product being ‘not classified’, eg test data not available
  • For mixtures, give mixture and appropriate component data

Technical compliance: classification, consistency, specificity


Hazard classification aims to determine whether a substance or mixture has physical, health or environmental hazards. It is a codification of the many and diverse ways in which a chemical can cause harm (see the Compendium of chemical hazards).

The hazard classification determines the pictograms and text required in the SDS and on the label, and is a cornerstone of hazard communication.

Around 4500 substances (out of around 120 000 substances in commerce) have mandatory harmonised classifications, as listed in Annex VI of the CLP Regulation (1272/2008). However, they are partial, minimum classifications so still require assessment to arrive at a correct and complete hazard classification.

In other cases, the SDS compiler uses non-mandatory classifications provided by others, or calculates the classification based on substance data and the criteria given in the CLP Regulation.

For mixtures, because toxicity test data is rarely available, the assessor usually derives the hazard classification from the hazards of the component substances and their percentages.

Data on substances, or components of mixtures, that are given in the SDS should be consistent with REACH Registration dossiers, which are available on the ECHA website.

It is uncommon for inspectors to check the details of mixture classification as presented in the SDS, but there are a few common mistakes that they can easily spot.

  • Substances listed in Section 3 (composition/information on ingredients) having a different classification to the harmonised classification
  • Where ingredient percentage ranges are given for mixture components, the highest value in the range should be used to calculate the product classification. In practice, it means that the percentage range listed in Section 3 (composition/information on ingredients) should not cross a classification concentration limit relevant to the component.
  • At pH extremes (< 2 or > 11.5), the product should be classified for corrosivity, unless there is further evidence to the contrary.

The new SDS Regulation (2020/878) emphasises the inclusion of data in the SDS Section 3 (composition/information on ingredients) to make transparent the derivation of the product classification in Section 2.1 (classification of the substance or mixture).

In particular for mixtures, the Regulation requires that specific concentration limits and acute toxicity estimates are included for the ingredients, so that a reader of the SDS has complete information for checking the product classification.

Classification checklist:

  • Check the classifications of the ingredients are consistent with harmonised classifications and REACH Registration data
  • Make sure the product classification in Section 2 is consistent with the composition in Section 3
  • Take care with percentage ranges for components as the highest value should be used for classification.

Internal consistency

The classification gives a codified summary of the hazards presented by the product. It is a useful starting place to check the SDS for internal consistency.

The consistency between the classification and percentage of the components of a mixture, and the classification of the product is mentioned above.

Hazard classification for a particular property should be clearly indicated in the relevant data Section.

For example a product classified as a Flammable Liquid, Category 3 should have relevant data in Section 9 (physical and chemical properties), particularly it should be a liquid with a flash point of 23 to 60 °C. This should be consistent with the firefighting measure (Section 5), accidental release measures (Section 6), and Transport information (Section 14).

If the product is described as a dusty powder, this should be reflected in the ‘Precautions for safe handling’ (Section 7.1) and the ‘Accidental release measures’ (Section 6).

Physico-chemical properties can also give an insight into likely effects on human health (given Section 11) and on the environment (Section 12). For example, a stable product with very low water solubility is unlikely to produce systemic toxic effects in mammals, or toxicity in the aquatic environment, as it is not biologically available.

Are human health hazards described in Section 11 consistent with the first-aid measures (Section 4)?

There are many other areas that an experienced SDS user can check to ensure that the SDS presents a consistent picture of the product and appropriate safety measures.

Consistency checklist:

  • Ensure the data Sections (9 for phys-chem, 11 for toxicology, 12 for ecotoxicology) are consistent with the product classification (Section 2) and the product composition (Section 3)
  • Make sure the risk management measures are consistent with the hazards of the product

Be specific

These requirements for specific details are difficult for compilers with limited time and an incomplete understanding of how the product might be used

A good SDS provides useful, specific information to users.

Unfortunately, most SDSs are machine generated, and do not have adequate adaptation to the products and its uses. This leads to overuse of generic statements that are unhelpful or misleading. The statement below are taken from a typical SDS:

  • Avoid all unnecessary exposure.
  • Equip cleanup crew with proper protection
  • Dispose of waste safely.
  • Handle in accordance with good industrial hygiene and safety procedures.
  • Comply with applicable regulations.
  • Provide adequate ventilation to minimize dust concentrations.
  • In case of insufficient ventilation: wear respiratory protection
  • Do not allow the product to be released into the environment.

The SDS should be specific and quantitative with regards to measures for safe handling of the product.

The legislation requires ‘detailed specification’ for personal protective equipment (PPE) such as type of respiratory protection. The glove material and thickness should be provided. ‘Good ventilation’ should be specified, eg 3 to 5 air changes per hour.

Thanks to REACH, and its requirement for communication in supply chains, manufacturers or importers should know how their product is used by downstream users.

Substances manufactured or imported above 10 tonnes per year have a chemical safety report (CSR), which contains exposure scenarios (ES), giving detailed operating conditions (OCs) and risk management measures (RMMs) needed for safe handling, for all uses, and for all parts of the substance’s lifecycle. See ext-SDS below.

The CSR also contains permitted and proscribed uses, which are included in Section 1.2 (relevant identified uses of the substance or mixture and uses advised against).

The limit concentrations for human health (Derived no-effect levels, DNELs) and the environment (Predicted no-effect concentrations, PNECs), available in the REACH Registration dossier, should be given for relevant substances in Section 8 (Exposure controls/personal protection).

The requirements for specific details are difficult for compilers with limited time and an incomplete understanding of how the product might be used, not to mention possible legal liability if specific information is found to be at fault, and few current SDS fully comply.

However, there is much publicly available information on substances on the ECHA website [1] in the disseminated REACH dossiers. The SDS should be consistent with the REACH dossiers and the CSR, and include the appropriate data on hazard classification, properties and recommended risk management measures.

Technical compliance checklist:

  • Be specific and use quantitative values when describing operating conditions and risk management measures, particularly regarding ventilation and personal protective equipment.
  • SDSs should contain the specific information provided in REACH dossiers, the CSR, and exposure scenarios for substances, appropriately integrated in the case of mixture SDSs.

Tailor the SDS to the product and the user

Machine-generated SDSs need thoughtful editing from humans with an understanding of the product and its uses.

Understanding the technical content of compliant SDSs may be beyond non-specialised recipients. If users do not understand the SDS, then the SDS is not fit for purpose, and the compiler has failed in their duty of care.

The SDS should be tailored to the expected experience and expertise of the user. A great way to do this is to provide non-technical interpretation alongside the complex numerical data. For example, in the ecotoxicity section, a statement such as: ‘no toxicity at the limit of solubility’ can be provided alongside loading rate data and effect concentrations in various aquatic species.

A common complaint is that SDSs have already become too long and complicated to be useful. This can be addressed only by suppliers recognising that more diligent compilation of the SDS is a worthwhile use of their resources, and by users demanding more from their suppliers. Hazard communication is a two-way process between supplier and user.

The technical content of compliant SDSs may be beyond many non-specialised users. If users do not understand the SDS, then the SDS is not fit for purpose, and the compiler has failed in their duty of care.

Finally, the SDS should reflect the hazards posed by the product.

While the classification is the main process for assessing the product, based on its intrinsic hazards, small packages or certain product types can reduce the hazards posed to the user, and this should be addressed in the SDS.

A common example is candles. The candle mixture may be classified as hazardous, owing to the properties of fragrance ingredients, but the small packages and encapsulation of the hazardous ingredients in solid wax reduces the likelihood of harm. The SDS should not exaggerate the potential for harm, or the risk management measures, based only on the classification.

For example, the following generic, unreasonable advice is given on the safety data sheet from a candle supplier: ‘Keep away from heat, sparks, open flames and hot surfaces. No smoking. Use personal protective equipment as required. Do not eat, drink or smoke when using this product.‘

Machine-generated SDSs need thoughtful editing from humans with an understanding of the product and its uses.

See previous blog post on SDSs for candles and diffusers.

National adaptation

SDS have never been ‘one-size fits all’ for GB, EU or any other country. There are national requirements that should be included. See previous blog post on authoring SDSs and labels for worldwide use.

Language and translation

EU countries and GB require SDSs to be provided in the national language. An SDS for use in GB should be in English, and an SDS for France should be in French.

For some EU countries, the language requirement is less obvious. Belgium has three official languages (French, Dutch and Belgium), and the language or languages required may depend on the region of supply.

Ireland allows SDSs to be supplied in English.

We are frequently asked who is responsible for the translation. The answer is not straightforward, because the legislation states only that the SDS should be in the correct language.

For import into the UK, the UK importer is responsible for ‘placing on the market’ and therefore also responsible for the SDS, including being in the correct language (English).

For UK export to the EU, then the UK exporter has no official role.

However, in both these cases, a condition of supply or an expectation of the customer may mean that the seller needs to provide a compliant, translated SDS, even when there is no legal requirement on them to do so.

Occupational exposure limit values (OELs)

Most countries have their own OELs, which should be reported in Section 8 (Exposure controls/personal protection). Definitive OELs can be found in national legislation, although it may be available only in the national language. There is a useful compilation, in English, on the Institut für Arbeitsschutz (IFA) website [2].

References to national legislation

Section 15 (regulatory information) should contain references to national information relevant to the product or its ingredients. It is difficult to fulfil this requirement with confidence, and the EU guidance documents do not provide clear answers.

Most countries have long lists of regulations relating to chemical use and workplace safety, eg for:

  • Occupational exposure limits, biological exposure limits, and workplace monitoring
  • Personal protective equipment
  • Worker safety, including special cases (young people, pregnant workers)
  • Storage and segregation
  • Explosive atmospheres
  • Major accident prevention
  • Special products, such as aerosols, carcinogens or lead
  • Emissions to water and air
  • Wastes

We recommend a pragmatic approach, and make reference to EU or UK Regulations and guidance where these cover the same area, and refer to national regulations where there is no equivalent, eg for OELs and the German Wassergefährdungsklassen (WGK).

Poison centres

The listing of poison centre details is a complex part of SDS compliance.

Within the EU, the procedures for poison centre notification are changing from national to EU-wide notification.

In some national poison centre schemes, a notification to a poison centre is required before the national emergency number can be used in Section 1.4 (emergency telephone number).

Multi-national compliance requires understanding the varied requirements and procedures, and dealing with national agencies in their own language.

The new EU scheme for poison centre notification (PCN) is centralised, and has harmonised information requirements. The PCN is made through the ECHA IT system. The PCN includes generating a unique formula identification (UFI) for mixtures, that is included in the SDS Section 1.1 (product identifier) and on the label.

See our services for poison centre notification here.

In GB, there is no mandatory PCN. Reference can be made in Section 1.4 to the National Poisons Information Service, noting that this is available only to healthcare professionals.

Extended safety data sheets (ext-SDS)

Ext-SDSs seem poorly understood by many suppliers and recipients.

The ext-SDS is the main method for the supplier to communicate the outcome of the chemical safety assessment (CSA) produced for REACH Registration, to the users of chemicals.

The CSA is a comprehensive risk assessment on a chemical substance to determine the risk management measures (RMMs) necessary to to maintain human and environmental exposures with safe limits, for all uses, for all stages of the chemical’s life.

This risk assessment involves the creation of ‘exposure scenarios (ESs)’, ie a description of the particular uses giving the RMMs to support safe handling and control of exposure.

The Downstream User has to implement to RMMs in the appropriate exposure scenario for their uses, or justify any departure.

A report by inspectors (REF-5 ) notes [3]:

In general, the poor quality of the examined chemical safety reports … does not support the generation of an accurate, understandable, verifiable and useful exposure scenario for communication to the (downstream) users of the substance.’

SDSs for substances usually have the required exposure scenarios from the CSA attached as an Annex. Substances are the most straightforward case, and here the ext-SDS may be useful to the recipient.

However, even for substances, inspectors have reported that the CSA is often not updated after significant changes to the REACH registration dossier, so that the substance ESs may be wrong.

However, most chemical products are mixtures. For mixtures, the OCs and RMMs from the chemical safety report of components can be integrated into body of the SDS, or the component exposure scenarios (ESs) appended as an Annex. The technical and practical processes of incorporating substance ESs into mixture ext-SDSs have been poorly thought through by the authorities, and poorly implemented by industry.

During inspections, extended SDSs for mixtures were found to be of poor quality, lacked required information, or uses were not covered. This makes it difficult for the recipients of the SDSs to see the value of the extended SDSs.

ECHA should take some responsibility for the poorly draughted requirements in the legislation and guidance, relying heavily on coded ‘use descriptors’ that are difficult to compare with real-life uses, and causing many compilers to create Exposure Scenarios with pages of codes and numbers rather than a readable description of practical safety measures.

Checklist for the ext-SDS:

  • For REACH Registrants, make sure the CSA is up to date.
  • Downstream users have a duty to make sure their use is covered in the CSA, so the use should be communicated to their suppliers for incorporation into the CSA, unless they are prepared to conduct their own downstream user CSA.
  • Registrants should put clear and practical, use-specific and self-explanatory risk management measures in the exposure scenarios, to be communicated in the ext-SDS.


There are many facets to compiling safety data sheets: formatting, hazard classification, data gathering, and safe use in the workplace.

Through legislation and guidance, the authorities provide an impossible list of demands and expectations, on the one hand for comprehensive and detailed information, and on the other for concise and understandable instructions for use.

There is a mismatch between highly technical SDS legislation and guidance, which is mainly targeted at chemical companies with expertise in chemical management, and many recipients of SDS who have only incidental understanding, such as professionals in engineering, coating, or construction.

In larger companies, increasing professionalisation of the health and safety function within a company, may mean that expertise in understanding SDSs may have become distanced from shop-floor use of chemical products.

The problems with SDSs are compounded by the use software-generated SDSs that are not properly checked and modified before being sent out. Compilers may err to the bland and generic in order to save time, and avoid being wrong.

Enforcement also plays a role by checking only the legal requirements, particularly formatting and completeness. Compilers are motivated to get these parts right to pass inspection.

A greater emphasis on the utility and ‘user-friendliness’ of the SDS is required. The legislation and guidance needs simplification. Inspectors and downstream users need to call out bad practice. Compilers need practical experience and communication skills to tell customers how to their products should be handled, and management need to see SDSs as an important part of product stewardship.

Otherwise we will still be complaining about the parlous state of SDSs in another 3 decades.


[back to Be specific] [back to occupational exposure limit values] [back to ext-SDS]

[1] ECHA website and Search for Chemicals:

[2] GESTIS International Limit Values; Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung (IFA);

[3] REF-5 Project Report; Extended safety data sheets, exposure scenarios, risk management measures and operational conditions; ECHA Forum; Adopted on 23.11.2018.

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