Join our Team
At the Health and Safety Council (HASC®), our people are the driving force behind building safe workplaces. Guided by our TIER values of Trust, Integrity, Excellence, and Respect, every role plays a vital part in helping our clients’ workforces stay safe, prepared, and ready.
Meet the Team Behind the Mission
Chief Medical Officer
Thomas “Tommy” Hysler, MD, MPH, FACOEM
Bill Christian, MD, MS, MPH
Medical Provider
Andrew Vargas, PA-C, NRCME
Medical Provider
Bryan Lee, MSN, APRN, FNP-C
Medical Provider
Diana Perez, PA-C
Medical Provider
Gregory Baker, MSN, APRN, FNP-C
Medical Provider
John E. Slaughter, MSN, FNP-C, APRN
Chief Medical Officer
Thomas “Tommy” Hysler, MD, MPH, FACOEM
Dr. Hysler has practiced Occupational Medicine since 2007, is board certified in Occupational Medicine, and is a Fellow of the American College of Occupational and Environmental Medicine (FACOEM). He is the Medical Director for multiple Contractor companies and frequently speaks at local, regional and national conferences such as National VPPPA, National Safety Council Congress, Texas Chemical Council and the American Society of Safety Engineers (ASSE). Dr. Hysler teaches a half-day course on OSHA Recordability (19OSHA) at HASC™ throughout the year, and also sits on the Residency Advisory Committee for the University of Texas Occupational and Environmental Residency program.
Education
- Bachelor of Arts, Louisiana State University
- Master of Public Health, University of Texas
- Doctor of Medicine, Ross University School of Medicine
- Occupational Medicine Residency, University of Texas (training at Shell, Chevron, ExxonMobil and others)
Additional Certifications
- Medical Review Officer (MRO)
- Disability & Impairment Rating Examiner
- DOT NRCME Medical Examiner
Bill Christian, MD, MS, MPH
Dr. Christian is passionate about health promotion and worker health, with a strong focus on developing programs that enhance employee well-being and reduce workplace risks. His work includes creating Total Worker Health initiatives and promoting wellness through health screenings and vaccination programs. By combining his expertise in occupational medicine with a deep understanding of public health, Dr. Christian strives to foster safer, healthier work environments that support long-term employee health and productivity.
Education
- Bachelor of Arts, Rollins College
- MS Degree in Medical Science, University of South Florida
- Master of Public Health, University of Massachusetts
- Doctor of Medicine, Ross University School of Medicine
- Occupational and Environmental Medicine Residency, University of Texas Health Science Center
- General Preventive Medicine Residency, University of Massachusetts Chan Medical School
Medical Provider
Andrew Vargas, PA-C, NRCME
Andrew has practiced in the field of Occupational Medicine for several years, during which he has educated various companies on exposure risk consistent with OSHA guidelines, and worked on-site at several local petrochemical facilities. After earning his undergraduate degree, he entered the medical field in 1998 when he accepted an Emergency Medicine position at the University of Texas Medical Branch–Galveston. After several years at UTMB, he moved on to pursue a career in private Gastroenterology and Infectious Disease practice, spending ten years serving his local community.
Education & Certifications
- Bachelor of Science, Physician Assistant Studies, Des Moines University
- DOT NRCME Medical Examiner
- NCCPA Board Certified Physician Assistant (PA-C)
Medical Provider
Bryan Lee, MSN, APRN, FNP-C
Bryan has practiced for more than 25 years in the fields of Family Medicine, Physical Therapy and Occupational Medicine. A graduate of Hardin-Simmons University with a Bachelor of Science degree and of Samford University with a Master of Science in Nursing, he is a certified DOT NRCME Medical Examiner and is board certified through the American Academy of Nurse Practitioners.
Medical Provider
Diana Perez, PA-C
Diana is a certified Nurse Practitioner (PA-C) and has worked across a variety of medical specialties since 2008. She graduated from the University of Houston with a Bachelor of Arts degree and from Nova Southeastern University with Bachelor of Science and Master of Medical Science degrees. She is a certified DOT NRCME Medical Examiner and is licensed to practice medicine by the Texas Medical Board.
Medical Provider
Gregory Baker, MSN, APRN, FNP-C
Gregg is a Family Nurse Practitioner, board certified by the American Academy of Nurse Practitioners, and has practiced Occupational Medicine since 1998. A graduate of the University of North Alabama with a Bachelor of Science degree, he went on to earn a Doctor of Chiropractic degree from Texas Chiropractic College. Gregg is also a certified DOT Medical Examiner (NRCME) and licensed by the Texas Board of Chiropractic Examiners.
Medical Provider
John E. Slaughter, MSN, FNP-C, APRN
A native Texan and an Eagle Scout, Dr. Slaughter specializes in occupational medicine, family practice, emergency medicine, pain management, orthopedics, neurology, bioidentical hormone replacement, nutrition, and chiropractic medicine. He is board certified in family practice with the American Academy of Nurse Practitioners (AANP), and certified as a Designated Doctor for the Texas Department of Insurance Workers Compensation Division.
Education
- Associate of Science, San Jacinto College
- Bachelor of Science, University of Houston
- Emergency Medicine Technician (EMT-B), San Jacinto College
- Bachelor of Science, Doctor of Chiropractic, Texas Chiropractic College
- Bachelor of Science in Nursing (BSN), Registered Nurse (RN), Hardin-Simmons University
- Master of Science in Nursing (MSN), Samford University
Additional Certifications
- Board Certified, Electrodiagnostics and Manipulation Under Anesthesia
- Board Eligible in Chiropractic: Sports Medicine, Neurology, Nutrition, Orthopedics
- Certified Provider for Buprenorphine/Suboxone by AANP/ASMHSA in Substance Abuse and Addictive Medicine
- DOT NRCME Federal Medical Examiner
Why Work at HASC?
Here, the work matters, and so do the people behind it. Our culture is intentionally built on Trust, Integrity, Excellence, and Respect, with room to grow, contribute, and be recognized along the way. We value character as much as credentials.
PURPOSE
For me, happiness comes from seeing someone understand something that could protect their life, watching a team embrace a safer way of working, and knowing that something I taught could prevent an injury or even save a life. I may be an employee delivering safety programs, but in my heart, I’m doing something much bigger. I’m helping build a culture where people matter, where doing the right thing matters, and where everyone has the opportunity to return home safely at the end of the day.”
Victor Marquez, CSST
Training Instructor
CULTURE
What sets HASC apart is that our values are lived, not simply stated. They show up in the everyday moments: how we work, how we treat one another, and how we approach challenges and opportunities. My time at HASC has shaped me both personally and professionally, challenging me to grow and showing me the impact a strong culture can have. That’s what makes being part of HASC so meaningful to me.”
Hailey McCoun
Account Manager
GROWTH
One of the things I value most about HASC is its commitment to developing people. I’ve had the opportunity to work across different business lines, support operations in multiple locations, and build relationships with talented teams throughout the organization. Those experiences have broadened my perspective, strengthened my leadership skills, and reinforced that growth happens when you’re trusted to take on meaningful challenges.”
Olivia Speyrer, MBA, MHA, SHRM-CP
Director of Health Operations
RECOGNITION
What makes HASC unique to me is that there’s a genuine culture of appreciation that makes people feel valued and excited to contribute. Recognition isn’t limited to leadership. Employees are encouraged to celebrate each other’s successes and acknowledge great work whenever they see it. In many ways, giving recognition can be just as rewarding as receiving it. Being able to share in a coworker’s success and see the positive impact it has on the team is incredibly rewarding. It creates an environment where everyone feels appreciated, motivated, and inspired to bring their best everyday.”
Maegan Dejean
Operations Process Manager
What We Do
Training
There’s a lot that goes into great training. Our teams teach, develop curriculum, create digital learning, lead hands-on skills development, administer testing and assessments, and coordinate the work that brings it all together.
Health
Keeping workers healthy and ready for the job takes a wide range of expertise. Our teams provide medical care, conduct testing and exams, collect specimens, perform diagnostic services, support telemedicine, and keep day-to-day clinic operations
Screening
Our Screening teams manage the details behind workforce screening programs. From background checks and drug and alcohol testing to records, results, program administration, and customer guidance, their work keeps programs organized and on track.
Technology
Technology at HASC goes beyond traditional IT. Our teams provide live online proctoring, administer platforms, manage information and records, assist users, and keep tools like LINK®, GateCheck™, iPQF, and eNotify running for the people who rely on them.
Why Join Our Team?
Looking back on my 16 years with HASC, I truly appreciate this company and the many opportunities it has given me. I’ve worked in several departments, which has given me a greater understanding of HASC as a whole and what makes it special. I believe connection, recognition, and the opportunity to grow are a big part of what makes HASC such an amazing place to work.”
Nellie Vargas
Supervisor of Baytown Operations
Find Your Next Opportunity
Ready for your next step? At HASC, you can build your career, take on new challenges, and work alongside people with a wide range of skills and experience. See current openings and find the role that’s right for you.
