Safety of electrical appliances

Risk – this is the probability combined with the severity that a particular characteristic of a product will cause injury.

Hazard – the risk of injury arises from product characteristics, and these characteristics are called hazards. Any feature of a product which has the potential to cause injury in certain circumstances is a hazard. The control of hazards in product design is called design risk management, and in manufacturing is called production control.

There are other modules that address safety in design for electrical products and conducting conformity assessments.

The main hazards with electrical products can be classified as follows:

• Electrical
• Fire and heat
• Mechanical

There are other hazards of a more product specific nature, for instance optical hazards caused by lasers in the product.

Electrical hazards

• Accessible live parts or components.
• Too short distances between current-carrying parts and accessible metal parts.
• Inadequate ingress protection allowing water to enter and get in touch with live parts.
• Products that break open if they are accidentally dropped and expose live parts.
• Poor supply cord anchorage.
• Low quality isolation that deteriorate over time due to thermal or mechanical stress.

Fire and heat hazards

• Hot surfaces or accessible heating elements that can be touched by the user or touch combustible material in the product.
• Poorly insulated or fixed wires or substandard components that short circuit and create arcs or overheating.
• Dirt or dust that build up inside the appliance and cause arcs.
• Blocking or prevention of the (cooling) airflow through the appliance.
• Malfunctioning overheating protection.
• Overloading of the product.

Mechanical hazards

• Accessible protruding parts, sharp or rough edges or surfaces on appliances.
• Heavy and unstable products.
• Accessible rotating or moving parts.
• Moving parts that splinter and eject parts out of the product.
• Accessible blades or knives in appliances.
• High sound pressure levels.