Reduced Speed or Reduced Energy

The assessment and risk reduction process is detailed in various standards.
An important aspect of the risk reduction methods suggested by the standards concerns the reduction of energy levels.

When possible, access to a segregated area should be carried out at zero energy with the elimination and isolation of hazardous energy (preferred method to reduce the risk). However, some activities require partial or total energization to be performed and to operate machine elements with disabled protection devices. For these specific activities, reduced energy operating modes are are a way to reduce the risk for the operator or the maintenance person.

Some types of machines are subject to specific standards  that define the operating modes in terms of reduced energy values and other additional conditions. 
However, many others, are not covered by a specific standard and therefore manufacturers may not know what threshold to use. 

Here we present some values stated in technical standards, grouped in the following way:

– Speed (mm / s): to be used in case of objects that move at constant speed (Robot arm).

– Force (N): in case of constant pressure without acceleration of the element.

– Kinetic Energy (J): to be used in case of objects that move at increased speed (a gate/protection falling from a certain hight).

– Pressure (N / cm2). In case certain part of the body is subject to the possible damage.