Our People

Sentinel Fire & Security was established in 1976 by Galen Hanselman in a small office in Hailey Idaho as the microprocessor was first introduced into electronic security detection industry and moved the office to Ketchum in the mid 1980’s.   In 1989, Mr. Henry Nicolai, who graduated locally from The Community School, purchased the business moving it once more to a North Main Street location. In 1999, he purchased Ketchum Alarm Company, another local company that was established in 1982 by Mr. Tom Bowman, and moved the business to a purpose built office on Lewis Street in Ketchum’s light industrial area.  Mr. Bowman now serves as Sentinel’s general manager

A small local company, Sentinel Fire & Security employs three full time installer/technicians (adding one or more helpers during the busy summer construction season), one full time office manager, five monitoring dispatchers as well as the general manager.

We are licensed in the State of Idaho and all of our technicians have specialty state electrical licenses.  We also maintain an Idaho public works license.

Our office in Ketchum is staffed 24/7/365 and we have four technicians living in Blaine County able to respond to after-hours service calls.  When you call our local number, 726-4788, you will get someone answering the phone in our office in Ketchum.  We do not own a telephone answering machine or voice-mail system because we never need them.

Many years ago, the owner of the company made the conscious decision to handle the monitoring of the alarm systems installed in Blaine County locally and we now provide that service for well over 2500 local customers.  Our monitoring station, although not having an expensive (for our size) UL listed pedigree, is a secure facility and has full redundancy in receivers and power generators.  We will not be affected by other power failures or telecommunication failures outside our region.  We also have a local network of radio transceivers as an option to our customers, to provide backup in the case of a premise or local telephone outage.

We are proud to be a locally owned and operated company and look forward to many more years in service to our community.


TomBowmanTom Bowman, General Manager with Sentinel since January, 2013: 32 years in Blaine County

Tom has been working in the alarm industry on and off since 1978 when he and his brother started an alarm company in San Diego.   After moving to Sun Valley “for a winter” in 1981, Tom started his own alarm company, Ketchum Alarm, which he sold to Sentinel  in 1999.  Tom was elected as a Blaine County Commissioner in 2004 and served until July of 2012 when he resigned to take the General Manager position at Sentinel.  Tom and his wife Patti have lived mid-valley since 1987 and raised two kids who are now in college.


MarkMargureguiMark Maguregui, Office Manager With Sentinel since 1994

Mark graduated from Boise State University with a degree in accounting in 1993 and been working at Sentinel since 1994. Mark manages all the aspects of the office and is an expert with our monitoring equipment and software.  Mark lives with his wife Paula in Hailey.


Bert Brammer, Bert does everything! With Sentinel and Ketchum Alarm since 1992

Bert was hired by Tom for Ketchum Alarm Company after he received his AA degree from Idaho State University.  Bert is an expert in designing alarm systems of all types, is called in for challenging  service issues and can install any low voltage system.  Bert and his wife Kathy live in Blaine County with their son Blake.



Kevin Johnston, Service and Installation 16 years with Sentinel
Born and raised in Blaine County, Kevin has been working at Sentinel full time since 1997, and before that, helped out during summer vacations from school. He lives with his wife Melissa and has two kids.                      







Casey Kelly, Installation and Service  with Sentinel since 2001

Casey is our “go-to” guy for difficult wiring problems and always enjoys a challenge.  Casey started with Sentinel soon after high school and has been a high performer ever since.  He lives with his wife Morgan and their young kids.





Jeannice Shiver, Service Technician with Sentinel since 1999   

Jeannice transitioned to part time after her kids came along and shares service call responsibilities with Bert on weekends and holidays.  She’s active in her church and lives with her husband Jeff and kids in Hailey and remains a loyal Aggie.