Hazards & Risks (Edexcel International AS Chemistry): Revision Note

Hazards & Risks

• The hazard of a chemical substance relates to the inherent properties of the substance

• The risk is more to do with how you plan to use it and the chance of it causing harm

• For example, water generally has no hazards however a beaker of water being boiled on a tripod and  gauze has several risks associated with it

  • The steam coming from the water and the boiling water could both cause damage if they came into contact with your skin

• Another example would be hydrochloric acid, a substance most people generally consider hazardous

• You will have been told to use eye protection when using the acid as it can potentially cause harm to your eyes

  • This is due to hydrochloric acid being corrosive

• This risk, however, depends on how likely it is the acid will get in your eyes

  • Using eye protection does not affect the hazard, but does decrease the risk

Hazard warning symbols

Table showing the most Common Hazard Symbols

Hazard Symbol	Meaning
	Health hazard	includes warning on skin rashes, eye damage and ingestion
	Corrosive	can cause skin burns and permanent eye damage
	Flammable	can catch fire if heated or comes into contact with a flame
	Acute toxicity	can cause life-threatening effects, even in small quantities

Risk Assessments

• Risk assessments can be used to help reduce the risk of certain hazards in a laboratory

• This is carried out by looking at the hazards of the chemical substances being used

• The way the substances will be used is considered to assess the risk associated

• Control measures or guidelines are then written in order to inform other people using the lab how to operate to reduce the risks associated with the chemicals

• Such guidelines will consider lots of different factors including:

  • The amount used

  • The age and experience of the person using it

  • Whether it will be heated

  • Whether ventilation or a fume cupboard should be used

• The control measures may include

  • The type of eye protection that needs to be worn

  • The need to wear gloves

  • Keeping a cap on a bottle after removing some of the substance

  • Keeping the substance away from a source of heat

  • What to do if some of the substance is spilt on the floor or gets on the skin