Existence Periods

In 4HSE, many elements can have their respective existence periods defined. These periods are extremely useful as they indicate when (for how long and how often) an element was part of your safety project.

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When Periods of Existence Are Not Applicable

Not all elements require a period of existence to be specified. Some are intrinsically tied to a specific date or fixed interval. Examples include:

• The edition of a course
• A medical examination
• A certificate

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Practical Example

A typical application of periods of existence is in managing seasonal workers.

Imagine an employee, Mario Rossi, who worked during two distinct periods:

• First Period: Worked from 2019-10-01 to 2019-12-01.
• Second Period: Was subsequently hired indefinitely starting from 2020-01-01.

The resulting periods of existence are:

	Start Date	End Date
Period 1	01/10/2019	01/12/2019
Period 2	01/01/2020	+infinite

Let’s assume that during his employment, the worker:

• was assigned to the Warehouse Management work phase
• attended a Forklift Operator Training course
• attended a General Training (4 hours) course
• was subject to an individual prescription protocol requiring the distribution of a high-visibility vest

These elements are considered child elements of the person element, which in turn acts as the parent. This creates a hierarchy:

• Mario Rossi
  |_ Warehouse Management
  |_ Forklift Operator Training
  |_ General Training (4 hours)
  |_ High-Visibility Vest\

This is a recurring concept in 4HSE and applies to many system elements.

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Inheritance of Periods of Existence

By default, elements in 4HSE have an infinite lifespan, ranging from minus infinity to plus infinity. However, it’s important to note that all elements with an unspecified period of existence implicitly inherit those of their parent elements, if the latter have been defined.

With this in mind, let’s assume the periods for the child entities are as follows:

Element	Start Date	End Date
Warehouse Management	15/10/2019	30/11/2019
Forklift Operator Training	05/10/2019	15/11/2019
General Training (4 hours)	inherited from Mario Rossi	inherited from Mario Rossi
High-Visibility Vest	10/10/2019	30/11/2019

As shown in the table, all elements except General Training (4 hours) have a specific existence period and will be displayed on the chart. In contrast, General Training (4 hours) inherits the existence periods from the parent Mario Rossi and therefore will not be displayed on the chart.

Any new child elements will inherit the periods from the person element. Similarly, although the person element may have parent elements, these are not displayed on the chart because they all have an infinite lifespan.

As you can see from the chart, all child element periods (in purple) fall within Period 1.

When adding or editing periods, the system assists in maintaining consistency with the periods of parent/child elements, ensuring that:

• for each period of the current element, there is at least one parent period that contains it
• for each child period, there is at least one period of the current element that contains it

Parent and child periods are not directly editable from this screen and must be modified via the period window of their respective element. For example, if you want to modify the existence period of the Forklift Operator Training for Mario Rossi, you must navigate to its detail form (Project/Office/Actions/Training/Courses/Forklift Operator Training/People/Mario Rossi) and click the

icon. This will open the following dialog window: