Sergeant Major Hernandez was born on 16 November 1982 in Selma, California. He enlisted on April 8, 2002 and attended recruit training at Marine Corps Recruit Depot San Diego, California. After completing Infantry Training Battalion at the School of Infantry as an infantry riflemen, Camp Pendleton, California, PFC. Hernandez was assigned to Alpha Company, 1st Battalion 5th Marines, Camp Pendleton, California.
In February 2003, PFC Hernandez deployed with 1/5 to Iraq for Operation Iraqi Freedom. With the high operational tempo of 5th Marines, Corporal Hernandez also deployed in March 2004 for Operation Iraqi Freedom II and in February 2005, for Operation Iraqi Freedom III.
In March 2006 Sergeant Hernandez attended Sergeant's Course in Camp Pendleton, California. In October 2006 Sgt. Hernandez graduated from Basic Recruiting School on Marine Corps Recruit Depot Sand Diego, California. Upon graduating Sgt. Hernandez was assigned to Recruiting Sub-Station West Vegas, Recruiting Station San Diego, California.
In December 2009, Sergeant Hernandez was assigned to Echo Company, 2nd Battalion 3rd Marines, Marine Corps Base Hawaii. In June 2010, Staff Sergeant Hernandez graduated from Infantry Unit Leaders Course at the School of Infantry, Camp Pendleton, California and later deployed to Operation Enduring Freedom, with Echo Co. 2/3. In October 2011, Staff Sergeant Hernandez graduated from the Staff Academy, Career Course, Camp Pendleton, California.
In 2012, Staff Sergeant Hernandez deployed on the first Marine Rotational Force Darwin, Australia with Fox Company 2/3. While in Australia, SSgt Hernandez conducted operation Landing Force Cooperation Afloat Readiness and Training (LF CARAT). During the deployment to Australia Staff Sergeant Hernandez conducted a Joint Corporals Course, where he was a faculty advisor.
In November 2013, Staff Sergeant Hernandez graduated from the Marine Security Guard School. Immediately upon completion of the school he was assigned to Detachment Phnom Penh, Cambodia, Region 3, as a detachment commander. In May 2015, Staff Sergeant Hernandez second post was Marine Security Guard Security Augmentation Unit (MSAU), Marine Corps Base Quantico.
In October 2015, Staff Sergeant Hernandez was promoted to Gunnery Sergeant. During his time with MSAU he led an augmentation mission to Bujumbura, Burundi and supported five Very Import Person (VIP) missions to Addis Ababa, Ethiopia; Paris, France; Guatemala City, Guatemala; Buenos Aires, Argentina; and Warsaw, Poland, in support of visits by the President of the United States (POTUS), Vice President of the United States (VPOTUS), and Secretary of State (SecState).
In November 2016, Gunnery Sergeant Hernandez was assigned to Marine Barracks Washington, where he participated in multiple Full Honor Funerals, Evening, and Sunset Parades. Gunnery Sergeant Hernandez was hand selected for a Joint State Honor Guard for the 41st President of the United States, George H. W. Bush.
In June 2020, he was promoted to the rank of First Sergeant and was assigned to 9th Engineer Support Battalion where he served as the Company First Sergeant for Bulk Fuel Company, Engineer Support Company and Headquarters and Service Company. In June 2023 First Sergeant Hernandez was assigned to Marine Wing Communications Squadron 18, Alpha Company.
In March 2024, Sergeant Major Hernandez was assigned to Recruiting Station (RS) Baltimore, where he currently serves as the RS Sergeant Major.
Sergeant Major Hernandez is married to Veronica and has a son, Sergio and a daughter, Kalani.
Sergeant Major Hernandez personal decorations include the Navy and Marine Corps Commendation Medal, the Navy and Marine Corps Achievement Medal, and Combat Action Ribbon.