CSA HGV 4.1-2020 pdf free download

CSA HGV 4.1-2020 pdf free download.Standard for hydrogen-dispensing systems.
5.12.2 Risk assessment
The manufacturer of the HFS shall conduct a safety review that shall include the review of the safety analyses of supplied systems and equipment.
The safety analyses may include a Hazardous Operations Review (HAZOP), or an FMEA, or equivalent risk assessment intended to identify failures that have significant consequences affecting the fuelling station operation.
5.12.3 Stop commands
The ESS shall issue an appropriate stop command in response to activation of a manual or control (e.g., sensor) device, based on the hazard assessment in Clause 5.12.2. Stop commands shall follow the requirements in
a) NFPA 79; or
b) CSA C22.2 No. 301.
5.12.4 Devices that activate the ESS
The ESS system should include multiple devices which can activate the ESS in response to a hazard and
may include
a) emergency stop buttons at the dispenser, compressor and/or HFS Module;
b) fire detection equipment (e.g., flame detectors or heat detectors);
c) combustible gas detection equipment within the compressor, HFS module and/or dispenser;
d) proximity switches for enclosures;
e) speed detection or motor overload detection;
f) positional limits for valves or actuators; or
g) controller watch-dog timer (WDT),
Response to activation of the device shall issue an appropriate emergency shut down command as determined by the hazard assessment in Clause 5.12.2.
5.12.5 Valve actuators
Activation of the ESS shall automatically place actuated valves within the HFS into a safe state based on a given stop command. This includes, but not limited to
a) isolation of bulk hydrogen system(s);
b) isolation of compressor inlet hydrogen supply;
c) isolation of supply from bulk hydrogen system(s) to dispenser(s); and
d) isolation of supply from dispenser to vehicle. CSA HGV 4.1-2020 pdf free download.