Testing in Lockout Tagout

Testing in Lockout Tagout

An enterprise carried out power off Lockout tagout and other energy isolation measures before the operation of the stirred tank overhaul. The first day of overhaul was very smooth and the personnel were safe. The next morning, as the tank was being prepared again, one of the workers became suspicious of yesterday’s isolation and pressed the start button. At this time, the blender turned, the kettle in the ladder, temporary lights and other tools all broken.

The near-miss is deeply frightening. Why this deviation? Is there a vulnerability in the Lockout Tagout manager? No, it’s a discount on execution. Specifically, the important part of “testing” was omitted.

Lockout Tagout full name: Lockout Tagout cleanup test manager. It consists of

Lockout tagout, cleaning and testing. Testing, on the other hand, is the most overlooked part. Now, let’s take a look at testing.

The purpose of the test is to confirm that hazardous energy or materials are effectively isolated and that locked equipment and power are actually cut off. For the operating equipment, the test method should consider the normal startup method and other unconventional operation methods, that is, to consider the button startup and interlock startup these two ways, but also consider the power is not cut off and the interlock will prevent the equipment from starting. When performing tests, block all restrictions such as interlocks that might prevent the device from starting. In addition, before turning off the switch of the power box, press the test button to verify that it works properly. After locking, perform a confirmation test to ensure that the power is indeed cut off.

To test the effect of hazardous materials and energy isolation, we should combine phenomena with special instruments and try to use data to speak for themselves. For example, for toxic, flammable and explosive, strong acid and alkali media, can be carried out by sampling assay analysis and instrument measurement; For medium such as high temperature and low temperature, it can be carried out by personnel rough perception and temperature measurement; For energy storage components such as springs and capacitors, the elastic shape variable and potential can be measured by instruments. In conclusion, only when people confirm their isolation status through objective phenomena and data can testing really work. Of course, it should also be noted that the surrounding area should be cleaned of personnel and equipment before testing.

In practical management, some enterprises require the start button of running equipment to be the isolation point for Lockout tagout. In fact, this is one of the reasons that the testing process is ignored. The management specification clearly states that buttons, selector switches and other control circuit devices cannot be used as hazardous energy isolation devices. Therefore, in addition to correct understanding, timely change of incorrect management is also the way to ensure that the test can be implemented.