You should be able to understand whatLO/TO means when you encounter it. is the means by which potentially hazardous energy sources are secured before work begins. This is NOT a LO/TO training program. The purpose of this presentation is to familiarize Security Officers (S/O’s) with LO/TO principles. Always check with the Facilities Manager or Engineers if you encounter LO/TO on site. Document any LO/TO placards you may find in your Daily Activity Report (DAR).