In a general sense, the design load is the maximum amount of something a system is designed to handle or the maximum amount of something that the system can produce, which are very different meanings. For example, a crane with a design load of 20 tons is designed to be able to lift loads that weigh 20 tons or less. However, when a failure could be catastrophic, such as a crane dropping its load or collapsing entirely, a

factor of safety In engineering, a factor of safety (FoS), also known as (and used interchangeably with) safety factor (SF), expresses how much stronger a system is than it needs to be for an intended load. Safety factors are often calculated using detailed analy ...

is necessary. As a result, the crane should lift about 2 to 5 tons at the most. In

structural design Structural engineering is a sub-discipline of civil engineering in which structural engineers are trained to design the 'bones and muscles' that create the form and shape of man-made structures. Structural engineers also must understand and calc ...

, a design load is greater than the load which the system is expected to support. This is because engineers incorporate a

safety factor In engineering, a factor of safety (FoS), also known as (and used interchangeably with) safety factor (SF), expresses how much stronger a system is than it needs to be for an intended load. Safety factors are often calculated using detailed analy ...

in their design, in order to ensure that the system will be able to support at least the expected loads (called specified loads, despite any problems with construction, materials, etc. that go unnoticed during construction. A

heater Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HV ...

would have a general design load, meaning the maximum amount of heat it can produce. A bridge would have a specified load, with the design load being determined by engineers and applied as a theoretical load intended to ensure the actual real-world capacity of the specified load.

See also