Meanings

There also are two slightly different meanings of safety, for example, home safety may indicate a building's ability to protect against external harm events (like weather, home invasion, etc), and the second that its internal installations (like appliances, stairs, etc) are safe (not dangerous or harmful) for its habitants.

Limitations

Safety can be limited in relation to some guarantee or a standard of insurance to the quality and unharmful function of an object or organization. It is used in order to ensure that the object or organization will do only what it is meant to do.

It's important to realize that safety is relative. Eliminating all risk, if even possible, would be extremely difficult and very expensive. A safe situation is one where risks of injury or property damage are low and manageable.

Types of safety

It is important to distinguish between products that meet standards, that are safe, and those that merely feel safe. The highway safety community uses these terms:

Normative safety

Normative safety is a term used to describe products or designs that meet applicable design standards.

Substantive safety

Substantive safety means that the real-world safety history is favorable, whether or not standards are met.

Perceived safety

Perceived safety refers to the level of comfort of users. For example, traffic signals are perceived as safe, yet under some circumstances, they can increase traffic crashes at an intersection. Traffic roundabouts have a generally favorable safety record, yet often make drivers nervous.

Risks and responses

Safety is generally interpreted as implying a real and significant impact on risk of death, injury or damage to property. In response to perceived risks many interventions may be proposed with engineering responses and regulation being two of the most common.

Probably the most common individual response to perceived safety issues is insurance, which compensates for or provides restitution in the case of damage or loss.

System safety and reliability engineering

System safety and reliability engineering is an engineering discipline. Continuous changes in technology, environmental regulation and public safety concerns make the analysis of complex safety-critical systems more and more demanding.

A common fallacy, for example among electrical engineers regarding structure power systems, is that safety issues can be readily deduced. In fact, safety issues have been discovered one by one, over more than a century in the case mentioned, in the work of many thousands of practitioners, and cannot be deduced by a single individual over a few decades. A knowledge of the literature, the standards and custom in a field is a critical part of safety engineering. A combination of theory and track record of practices is involved, and track record indicates some of the areas of theory that are relevant. (In the USA, persons with a state license in Professional Engineering in Electrical Engineering are expected to be competent in this regard, the foregoing notwithstanding, but most electrical engineers have no need of the license for their work.)