Siemens SIMATIC KP8 Operating Instructions Manual page 24

Safety instructions and approvals
2.4 Notes about Usage
Operation in potentially explosive atmosphere, zone 2 and 22
Degree of hazard
There is an explosion hazard when operating an HMI device that does not have explosion
protection.
Operate the HMI device in potentially explosive zones 2 and 22 only if it has been approved
and certified for such environments.
If an HMI device is operated in potentially explosive atmospheres of zone 22, pay attention
to the product information "Use in potentially explosive atmospheres of zones 2 and 22." The
product information is available at the following Internet address:
Technical Support (http://support.automation.siemens.com/WW/view/en/4000024)
Personal injury and damage to property
Personal injury and property damage can occur in potentially explosive atmospheres if an
electric connection is disconnected from the HMI device while the system is in operation.
In potentially explosive atmospheres, always turn off power to the HMI device before
disconnecting any electrical connections..
Potentially explosive atmosphere zones 2 and 22
Areas subject to explosion hazard are divided into zones. The zones are differentiated
according to the probability of the existence of an explosive atmosphere.
Zone
2
22
Safe zone
24
DANGER
WARNING
Degree of hazard
Explosive gaseous atmosphere occurs only
seldom and for a short period
Area in which a potentially explosive
atmosphere in the form of a cloud in the air
containing flammable dust does not usually
occur or occurs only briefly during normal
operation .
No
Example
Areas around flanged pipe joints
with flat gaskets in closed rooms
–
Outside zone 2

Outside zone 22

Standard applications of

distributed I/Os
Operating Instructions, 10/2010, A5E03284305-01
KP8, KP8F