A support apparatus capable of communicating with a control apparatus (2; 200) network-connected to one or a plurality of safety devices, wherein each safety device has a memory part for keeping device identification information that specifies a device itself, and the support apparatus comprising: an obtaining part (S100, S104), configured to refer, in each network, to a connection setting list that defines network identification information set for the network to which each safety device belongs and network addresses of the one or a plurality of safety devices belonging to the network, and configured to obtain status information respectively from the one or a plurality of safety devices network-connected with the control apparatus (2; 200) based on the network identification information and the network addresses of the one or a plurality of safety devices from the connection setting list; a selecting part (S108, S110, S120-S134, S138, S146), configured to select, based on the status information of each safety device, a safety device to which the device identification information is to be newly set among the one or a plurality of safety devices to which the status information is obtained; and a setting part (S112, S136, S150, S152), configured to determine and set corresponding device identification information for each of the selected safety devices in accordance with an instruction from a user based on network identification information and the network addresses of the one or a plurality of safety devices; wherein the setting part is configured to obtain, from the device identification information already set to any safety device, the network identification information of the network to which the safety device belongs, and is configured to determine and set the device identification information for other safety devices belonging to the same network as the safety device based on the obtained network identification information; and wherein the device identification information is determined by combining an IP (Internet Protocol) address of a target safety device and a SNN (Safety Network Number) set to the network to which the target safety device belongs, the network identification information is a SNN, each of the network addresses of the safety devices is an IP address. an obtaining part (S100, S104), configured to refer, in each network, to a connection setting list that defines network identification information set for the network to which each safety device belongs and network addresses of the one or a plurality of safety devices belonging to the network, and configured to obtain status information respectively from the one or a plurality of safety devices network-connected with the control apparatus (2; 200) based on the network identification information and the network addresses of the one or a plurality of safety devices from the connection setting list; a selecting part (S108, S110, S120-S134, S138, S146), configured to select, based on the status information of each safety device, a safety device to which the device identification information is to be newly set among the one or a plurality of safety devices to which the status information is obtained; and a setting part (S112, S136, S150, S152), configured to determine and set corresponding device identification information for each of the selected safety devices in accordance with an instruction from a user based on network identification information and the network addresses of the one or a plurality of safety devices; wherein the setting part is configured to obtain, from the device identification information already set to any safety device, the network identification information of the network to which the safety device belongs, and is configured to determine and set the device identification information for other safety devices belonging to the same network as the safety device based on the obtained network identification information; and wherein the device identification information is determined by combining an IP (Internet Protocol) address of a target safety device and a SNN (Safety Network Number) set to the network to which the target safety device belongs, the network identification information is a SNN, each of the network addresses of the safety devices is an IP address.