Our industry require several basic knowledge, which is summarize to this list of question.
Gas is a phase or the simplest condition of an object. It consists of particles that are able to flow and change its form. Commonly, a substance called gas when it boils in atmosphere pressure and in the 273.15oC temperature until 26.7oC temperature.
Some gasses has flammable characteristic, such as Acetylene and Hydrogen. But there must be oxidation factor (oxygen), fuel and fire source for a burning. The burning should not be happened if one of them is absence.
The air surround us contains of 78% Nitrogen, 21% Oxygen and 1% other gasses. The source producing Nitrogen is the air that is separated through the process distillation (based on the difference in boiling point) and adsorption. This air separating process produces Nitrogen, Oxygen and Argon.
Nitrogen is an inert and dry gas. Dry Nitrogen will prevent burnings, corrosion in rim of wheel, and help tires work with cooler temperature than air.
Averagely, Nitrogen-pumped-tires are 26% stronger than air-pumped-tires. Tire damage is caused by Oxygen in the air. Oxygen reacts with rubber chemically, makes rubber loses its power and elasticity. Air diffusion through tires is 30-40% faster than Nitrogen and it results in flat tires. Although light car tire (SUV) will lose 0.5 pressures to 1 kgf per month in optimal condition. It is predicted that 30-50% of cars in street are operated in lack of air pressure condition that cause the increase in fuel consumption.
Dry Ice is the solid form of Carbon Dioxide. Its maximum temperature is -78,64oC. Dry Ice is made by compressing Carbon Dioxide to rise its pressure and condensed it into liquid phase. This liquid is expanded into grains like snow. The snow is compressed into beam called Dry Ice.
In several cases, Hydrogen is safer than Hydrocarbon liquid. Because of its light characteristic, Hydrogen tends to rise up to the air when there is leak. It will not soak the clothes like oil fuel which is burnt directly when there is fire sprinkling. When a car with Hydrogen gets burnt, the temperature inside the car will only rise 1-2oC. Hydrogen with no carbon will be burnt and do not produce residue in the form of particles. But when Hydrocarbon gets burnt, it will produce particles that will transfer the heat to environment, including you.
Cryogenic liquid is a gas liquefied in atmosphere pressure and an extremely low temperature, under -101 oC. Examples of Cryogenic liquid are liquid Nitrogen, liquid Oxygen and liquid Helium.
Small capacity (150-250 liters of Cryogenic liquid) may use Portable Liquid Container (PGS), while the large capacity uses Lorry Tank. There is vacuum room in the middle of both distribution facilities which intends to prevent heat movement from environment to cylinder.