Free Online Hazmat/Hazchem Guide

Free Hazmat (Hazardous Materials)/HazChem (Hazardous Chemicals) Guide containing information on Supply Labels, Hazard Warning Panels, Hazard Warning Diamonds, Emergency Action Codes and more

 Hazchem Scale Cards

Helping you manage chemical safety



More information on Hazchem Scalecards

This handy-sized reference guide gives you information on:

  • GHS Labels
  • Hazchem Warning Panels, Emergency Action Codes, ADR 2013
  • Hazard Identification Numbers (HIN) 
  • Hazard Warning Diamonds and Supply Labelling

 The Hazard Warning Panel

 Emergency Action Codes (EAC)

The EAC provides information on:

  • The fire extinguishing media to be used
  • The level of PPE required 
  • Whether the spillage should be contained or may be diluted 
  • Whether there is a possibility of violent reaction 
  • Whether the substance poses a Public Safety Hazard


Further Advice

More detailed advice on interpreting EAC is given in The Dangerous Goods Emergency Action Code List 2013 which you can buy as a book from TSO (ISBN 9780117541184) or download free.

 International Operations (ADR)

The ADR Hazard Identification Number (HIN, also known as the Kemler Code) is usually found in the UK on vehicles which are on international journeys. UK registered vehicles on domestic journeys should use the EAC. The HIN differs in its approach from the EAC, giving advice on the nature of the hazard presented by the goods as opposed to the actions to be taken when dealing with them.

 Blank Plates

Orange plate without any numbers indicates vehicle carrying dangerous load (drums, packages, etc.) or multi-load tanker.

 The Hazard Identification Number (HIN)

The hazard identification number consists of two or three figures. In general the figures indicate the following hazards:

2 Emission of gas due to pressure or to chemical reaction
3 Flammability of Liquids
4 Flammability of solid or self-heating liquid
5 Oxidising (fire-intensifying) effect
6 Toxic or risk of infection
7 Radioactivity
8 Corrosivity
9 Risk of spontaneous violent reaction

Doubling of a figure indicates intensification of that particular hazard.
If the HIN is prefixed with an "X" this indicates the substance will react dangerously with water. For such substances, water may only be used by approval of experts.

Where the hazard associated with a substance can be adequately indicated by a single figure, this is followed by a zero.
The following combinations have special meanings - refer to Hazchem List or control:

22 Refrigerated liquefied gas, asphyxiant
323 Flammable liquid which reacts with water, emitting flammable gases
333 Pyrophoric liquid
362 Flammable liquid, toxic, which reacts with water, emitting flammable gases
382 Flammable liquid corrosive, which reacts with water, emitting flammable gases
423 Solid, flammable solid or self-heating solid which reacts with water, emitting flammable gases
432 Spontaneously flammable (pyrophoric) solid which reacts with water, emitting flammable gases
44 Flammable solid, in the molten state at an elevated temperature
446 Flammable solid, toxic, in the molten state at an elevated temperature
462 Toxic solid which reacts with water, emitting flammable gases
482 Corrosive solid which reacts with water, emitting flammable gases
539 Flammable organic peroxide
606 Infectious substance
623 Toxic liquid which reacts with water, emitting flammable gases
642 Toxic solid, which reacts with water, emitting flammable gases
823 Corrosive liquid which reacts with water, emitting flammable gases
842 Corrosive solid which reacts with water, emitting flammable gases
90 Environmentally hazardous substance; miscellaneous dangerous substance
99 Miscellaneous dangerous substance carried at an elevated temperature

 Hazard Warning Diamonds

Class 1
Explosive substance or article
Class 2

Class 3
Flammable liquids  

Class 4.1
Flammable solids,
and desensitised explosive    

Class 4.2
Substances liable to
spontaneously combust
Class 4.3
Substances which, in contact
with water emit flammable gases
Class 5.1
Oxidizing substances   
Class 5.2
Oxidizing peroxides

Class 6.1
Toxic substances
Class 6.2
Infectious substances  
Class 7
Radioactive material 
Class 8
Corrosive substances     
Elevated Temperature
Class 9
Miscellaneous dangerous
substances and articles     

Environmentally hazardous /
Marine Pollutant
Risk of Asphyxiation      

 Supply Labelling


Toxic / Very Toxic
Dangerous for the Environment
Highly / Extremely Flammable
Harmful / Irritant

Supply labelling uses the same, or similar symbols to those seen on the Hazard warning diamonds used for transport labelling. However, as well as being a different shape and colour, different criteria are used to assign the risks. So, something classified as "Toxic" (Class 6.1) for transport may only be classified as "Harmful" for supply. Equally, something classed as "Toxic" (skull and cross-bones) for supply, such as a carcinogenic substance, may not be classified as hazardous for transport at all.

Equally, a particular substance may have different classifications for each system. Solvents may be classed as "Flammable" (Class 3) for transport, but "Harmful" or "Toxic" (equating to class 6.1) for supply. The reasons for this are the different types of risk exhibited in different situations. The end user, dealing with small quantities on a frequent basis over long time-periods, is at greater risk from any harmful/toxic effects due to contact with the product than from its flammable characteristics. The Emergency Services, however, will be dealing with a "one-off" situation which is not supposed to happen ever, involving several drums or tankerloads of the product, where the flammability hazard far outweighs the effects of contact with the product.

Classification can therefore be more intricate than it first appears; if you need any advice or guidance, see the Consultancy pages on this website.

 GHS Labels

GHS is the internationally agreed Globally Harmonised System of Classification and Labelling of Chemicals. GHS aims to improve the health and safety of workers, consumers and the environment by ensuring consistent hazard communication on the chemicals being used.

In the EU, GHS has been implemented through the CLP Regulation (EC) No 1272/2008.

More information on GHS

Extremely self-reactive/
Organic Peroxide
Pressurised gases/
Compressed gas/
Liquefied gas/
Refridgerated liquefied gas/
Dissolved gas
Emits flammable gas/
Organic peroxide
Corrosive to metals/
Corrosive to skin/
Severe eye damage
Acutely Toxic
Health hazard/
Reproductive toxicity/
Specific target organ toxicity/
Aspiration hazard/
Respiratory sensitiser
Skin sensitiser/
Specific target organ toxicity/
Narcotic effects
Hazardous to the environment


Chemical Emergency Response Service
NCEC’s 24/7 chemical emergency response helpline provides prompt, expert emergency advice when the worst happens. Our emergency responders are on hand to help you prepare and deal with chemical accidents by providing unparalleled support and advice to protect people, property and the environment.

Chemdata provides clear, concise advice and information for Hazmat incidents that is written in plain everyday language. The database provides information and advice on over 50,000 substances and is continually reviewed and updated by NCEC’s emergency responders – who are all qualified chemists. Chemdata is constantly growing, ensuring you have access to an ever-increasing breadth of information that is accurate and timely. It is available in several languages including English, Dutch, French, German and Spanish.

ChemeDox is an online, simple-to-use, SDS and chemical-safety document management system. The software allows you to effectively manage chemical safety information, while enabling you and your organisation to save money, work more safely and, equally importantly, comply with appropriate legislation. This simple-to-use system enables staff across your organisation to access chemical safety information like SDSs and COSHH assessments 24/7, thus helping them to understand the broader risks associated with using chemical products in the workplace.

SDS Services
Organisations involved in the supply of hazardous chemicals are required by law to provide customers with SDSs providing information on managing chemicals safely at work. NCEC can assist with all your SDS requirements – from compliance reviews and product classification, to regional regulatory template setup and translation services (in over 40 languages). We provide ongoing regulatory tracking, notifications and updates helping mitigate risks in an ever changing regulatory arena.

Training and Compliance
NCEC has the expertise and services to help you comply with legislation. We also help to ensure you and your staff are trained and prepared to cope with a range of chemical safety scenarios. Our services include training on practical and regulatory topics, REACH Consultancy, SDS authoring, Control of Substances Hazardous to Health (COSHH) assessments, toxicology consultancy, and emergency planning and business continuity advice.