An installation for intervention in a well, comprising: - a lower assembly intended to be lowered in a well comprising a neutron generator and a power source electrically connected to the neutron generator; - a surface assembly comprising one or more safety devices (50, 52), each safety device being either in a safe state or an unsafe state; - communication module that connects the lower assembly and surface assembly; wherein the surface assembly comprises a surface transmitting device for transmitting data to the downhole assembly via the communication module wherein the lower assembly is configured to trigger the operation of the neutron generator only if the activating command has been received and to stop the operation of the neutron generator upon reception of the stopping command wherein the surface assembly comprises at least a detection device, each associated with at least one of the safety devices and configured to determine whether said safety devices are in a safe state, characterized in that at least one of the safety devices comprises a measuring device of a parameter relative to the lower assembly, the associated detection device being configured to compare a measured value of the parameter to a predetermined threshold value, wherein the parameter is a depth of the lower assembly and characterized in that the surface transmitting device includes: - a first transmitter for transmitting an activating command, configured to transmit the activating command only if each of the safety device is in a safe state, and - a second transmitter for transmitting a stopping command, configured to transmit the stopping command if one of the safety devices is in an unsafe state. - a lower assembly intended to be lowered in a well comprising a neutron generator and a power source electrically connected to the neutron generator; - a surface assembly comprising one or more safety devices (50, 52), each safety device being either in a safe state or an unsafe state; - communication module that connects the lower assembly and surface assembly; wherein the lower assembly is configured to trigger the operation of the neutron generator only if the activating command has been received and to stop the operation of the neutron generator upon reception of the stopping command wherein the surface assembly comprises at least a detection device, each associated with at least one of the safety devices and configured to determine whether said safety devices are in a safe state, characterized in that at least one of the safety devices comprises a measuring device of a parameter relative to the lower assembly, the associated detection device being configured to compare a measured value of the parameter to a predetermined threshold value, wherein the parameter is a depth of the lower assembly and characterized in that the surface transmitting device includes: - a first transmitter for transmitting an activating command, configured to transmit the activating command only if each of the safety device is in a safe state, and - a second transmitter for transmitting a stopping command, configured to transmit the stopping command if one of the safety devices is in an unsafe state. - a first transmitter for transmitting an activating command, configured to transmit the activating command only if each of the safety device is in a safe state, and - a second transmitter for transmitting a stopping command, configured to transmit the stopping command if one of the safety devices is in an unsafe state.