Philips HEARTSTART XLT M3500B - Manual (Page 117)

Operational Checks
M3500B HeartStart XLT Defibrillator/Monitor 11-3
11
Every Shift
Perform a “Shift/System Check” every shift (see “Shift/System Check” on
page 11-4) to verify that the HeartStart XLT is functioning properly and to
ensure that necessary supplies and accessories are present and ready for use.
Every Month
Check expiration dates on multifunction defib electrode pads and monitoring
electrodes every month. Replace them if the expiration date has passed.
Every Three Months
Perform a "Battery Capacity Test" on each battery, every three months, to
ensure that your batteries meet the specifications for safe and effective use.