SESHA Webinar
LOTO Design Challenges

June 12, 2019, 4:00 PM EST


The complex term “CoHE” is more commonly referred to as “Lock-Out/Tag-Out” or “LOTO” but they are not the same. CoHE is a wide-ranging term describing the use of procedures, techniques, and specific equipment designs to prevent unintentional energizing or the release of stored hazardous energy, which can lead directly to harm. LOTO is simply one of the most common administrative methods in which to do this.
Common Examples of Hazardous Energies In Semiconductor Industry

- Distributed Electrical (high voltages, high currents)
- Stored Electrical (capacitors, batteries)
- Pressurized Liquids (hydraulic, pumped)
- Compressed Gases (liquefied, or pressurized)
- Electromagnetic Radiation (X-Ray, RF, IR, UV, lasers)
- Static Magnetic Fields (permanent magnets)

- Gravitational Energy (e.g. suspended, hinged loads)
- Kinetic Energy (moving robots, linear drives, gears)
- Thermal / Cryogenic Energy ( hot, cold temperatures)
- Chemical Energy (heat of reaction, fire, explosion)
- Stored Mechanical Energy (springs, elastic seals)
- etc.

Unfortunately, due to the semiconductor equipment design and fab layouts, certain LOTO procedures can be inconvenient, complicated and slow. Based on a previous semiconductor industry survey related to the Lockout/Tagout, the equipment suppliers, the end-users (fabs), and the third party evaluators have each highlighted obvious differences of opinion related to the semiconductor industry’s LOTO practices.

This SEMI survey’s results helped the SEMI EHS Committee to justify the formation of a SEMI Task Force to address these important LOTO interpretation inconsistencies from a global perspective. The webinar will focus on key topics to be considered to improve our CoHE / LOTO guidance. It is the hope that new text of SEMI S2 can be clarified, and other important design and administrative considerations to prevent foreseeable misuse during maintenance/service task.


Presenter: Mark Fessler; MS, FS Eng
Director: Global Product Safety Engineering
ASM, International N.V.