Final answer:
The maximum allowable psi of fueling nozzle pressure for the Beta-Freightliner R-12 Hydrant-Servicing Unit can vary based on the model and manufacturer specifications. Consult the user manual or contact the manufacturer for the specific psi rating.
Step-by-step explanation:
The maximum allowable pounds per square inch (psi) of fueling nozzle pressure used with the Beta-Freightliner R-12 Hydrant-Servicing Unit depends on the specific model and manufacturer specifications. To find this information, you should refer to the user manual or contact the manufacturer directly. They will be able to provide the accurate psi rating for the fueling nozzle.