bbforks
this is the reality these days for some companies, especially some of the larger companies that are trying to achieve ISO certifications.
Lock out Tag out has been a part of OSHA regulations for a long time now it's just gotten more prevelant in the past few years due to the tighter regulations being put forth to some of these companies dealing with hazardous materials or environments.
If you want to read up on the OSHA proceedures on lock out tag out you can go here:
h t t p s://w w w.osha.gov/SLTC/controlhazardousenergy/
(just remove the spaces i added in this url)
or you can just google 'lock out tag out osha' and it will provide you a link to the page.

There are many types of hazardous energy sources you may have to deal with so they have all sorts of devices you can use to lock out equipment. When you look for lockout devices you will need to specify 'forklift' devices in your searches as these devices are made specifically for lift trucks for locking out battery cables, battery plugs etc.

In most cases like brewski said the employer is responsible for your training and must provide the devices for you to use, with you being an independent tech you are responsible for this yourself.
You may even want to keep the evidence of having the training in case someone asks you about it.