From Sequoia and Kings Canyon National Parks:  ( Link is here )

Quote:
ADVISORY: EMERGENCY SATELLITE LOCATOR DEVICES

Using the SOS or 911 button on a satellite-locator device carries the same responsibility as dialing 911 from a telephone. Use these devices only to request help in a true emergency. Ask yourself, Are you willing to put other people at risk to solve your problem?

Please read this entire advisory before your trip in order to understand your responsibilities and the consequences of your actions. Know that rescues are risky to personnel and expensive to agencies.

Take note: Even if you activate the emergency beacon on a SPOT, PLB, or similar device, response may take longer than 24 hours depending on weather, time of day, your location, and other factors.

Responsibilities before leaving home:
  • Know and consider your personal skills and limitations in regards to your planned wilderness travel. Wilderness is a place for personal challenge, responsibility, and self-reliance.
  • Read the instructions for your device; keep them with you. Understand how it works and what services provided by the manufacturer must be activated and purchased. If required, register your device and provide all the information requested.
  • Some devices (e.g. SPOT) ask for a primary contact in the case of an emergency activation. Do not start your trip until that person has complete details, including:
    1. Your intended route; alternate routes you might take; when and where you plan to start and end; knowledge about your experience level; and gear you are taking.
    2. Full names of all members of your party and their emergency contacts.
    3. The difference between HELP and SOS/911 on a SPOT-type device: HELP does not indicate an emergency; it signals only your chosen contacts. They should know what to do if they receive a HELP signal (e.g., hike or drive to your location). The NPS will not respond to HELP as an emergency unless they have additional information. If you have a true emergency, activate SOS/911.
    4. How to access your tracking webpage, including login and password. Knowing your prior waypoints or tracking information may help NPS to respond.


Responsibilities during your trip:
  • Your knowledge, experience, and equipment will contribute most to your survival. Can you self-rescue or get help from other hikers? Do not signal SOS/911 unless it is a true emergency, but do not be afraid to signal if you know it is justified.
  • If you activate SOS/911 and it is safe to stay where you are, don't leave. It may be harder for rescuers to find you. Stopping the SOS/911 signal or activating the OK signal may not cancel a response, so stay in the areas where you activated the SOS/911 even if the emergency has passed.


Responsibilities after your trip or emergency
  • If you activated the SOS/911 but have not been contacted by NPS or other agency personnel, call the agency immediately once you are out of the wilderness; we may be looking for you. Sequoia and Kings Canyon National Parks' 24-hour dispatch phone number is 559-565-3195.
  • Let your contact(s) know as soon as you are out and not in need of help.

Remember: Your locator device is only a tool. Activate SOS/911 only in a true emergency. In that event, the NPS will do everything possible to help you.