Page 68 - CNG/ LNG ESP Participant Guide 2024

Module 8: LNG Vehicle Systems and Safety Practices

Methane Gas While optional for CNG maintenance facilities,
Detection Systems methane gas detection systems are REQUIRED
by code for all LNG maintenance facilities

When present, the methane gas detection
system detects methane at potentially unsafe
levels inside a maintenance facility. The
methane gas detection system:

▪ Activates at 25% LFL and may perform some
or all the following:
o Activates an exterior red light
o Activates internal audible/visual alarms
o Activates emergency exhaust fans
o Activates and opens make-up air (roll-up doors, etc.)
o Deactivates heating system
o Deactivates welding receptacles
o Notifies your organization’s security department
o Notifies fire department, if required

Module 8: Knowledge Check

Saturated LNG systems are those that use LNG that has been:
□ Vented
□ Frozen
□ Stored
□ Warmed

LNG fuel systems operate at relatively low pressures.
□ True
□ False

One of the main differences between CNG and LNG vehicles is:
□ LNG vehicles cost more
□ LNG vehicles vent regularly as a normal part of their operating process and CNG vehicles do not
□ CNG vehicles vent regularly, and LNG vehicles do not
□ CNG is unodorized and LNG is odorized

NGV Essentials and Safety Practices (CNG & LNG) © 2024 AFVi All Rights Reserved Page 8-10