Patent ID: 8791820
Filing Date: 2014-07-29
Classification: E05B,E05C,G08B,Y10T

Abstract:
1. A hazard alarm method comprising: using a control of a hazardous device, providing the hazardous device in a reduced hazard state which presents less risk compared with another state of operation of the hazardous device; locking the control of the hazardous device to maintain the hazardous device in the reduced hazardous state; locking alarm circuitry to the hazardous device; using the alarm circuitry locked to the hazardous device, monitoring a state of the locking of the control of the hazardous device; during the monitoring, detecting a change in the state of the locking of the control of the hazardous device; as a result of the detecting, generating an alarm signal to indicate the change in the state of the locking of the control of the hazardous device; wherein the locking the control of the hazardous device and the locking alarm circuitry individually comprise locking a lock system to the hazardous device using a plurality of locks, and further comprising: removing all of the locks from the lock system to unlock the lock system; and removing the unlocked lock system from the control of the hazardous device after all the locks have been removed, and wherein the detecting comprises detecting the removal of the unlocked lock system from the control of the hazardous device, and the generating comprises generating the alarm signal only as a result of the removal of the unlocked lock system from the control of the hazardous device after all of the plurality of locks have been removed.