The difference is that 30 is used for health preservation and 90 is used for cor pulmonale. Machines with 30% concentration are also called oxygen-enriched concentration oxygen generators, and those with 50% concentration are called oxygen-enriched. Oxygen enrichment is harmless to human body, does not produce oxygen poisoning and oxygen dependence, and is mainly used for health preservation.

90% oxygen generator is also called medical oxygen generator. 90% oxygen generator can't take oxygen for a long time, and it will be aerobic dependence. Only when doctors suggest that long-term oxygen inhalation is needed, or when you have severe emphysema, asthma, pulmonary heart disease, etc., can you use it. , but pay attention to control the oxygen inhalation time.

Conventional oxygen concentration refers to the oxygen concentration inhaled into alveoli, that is, the concentration inhaled into lungs, not the concentration of oxygen sources.

Medical definition: oxygen concentration (especially oxygen concentration in alveoli) is below 30%, which is low concentration; The oxygen concentration is between 30% and 50%, which is a medium concentration; Oxygen concentration higher than 50% is a high concentration. Inhalation of high-concentration oxygen with concentration greater than 50% may cause oxygen poisoning for 2 consecutive days; When the inhaled oxygen concentration is higher than 80%, oxygen poisoning may occur within 12 hours.

The reasonable oxygen concentration is 24%-33%, which is also the most suitable concentration for oxygen exchange in alveoli. Therefore, it is suggested that the flow rate of treatment and health care should not exceed 5L/ min. The purpose of finding a reasonable oxygen concentration (flow rate) is to consider factors such as economic cost. If the flow rate is 1.5L/ min, the therapeutic purpose can be completely achieved.

When the oxygen concentration is adjusted to 2.5L/ min, the effect is the same, but 1L oxygen is wasted every minute. On the other hand, if the oxygen concentration is not enough, it will have no effect. Therefore, in the early stage of oxygen inhalation, it is necessary to find the oxygen concentration suitable for users under the guidance of doctors.

In order to make oxygen concentration effective, we need to know the relationship between typical oxygen output flow and oxygen concentration. In medicine, when the output gas flow concentration is about 100%, the oxygen absorption concentration when using nasal oxygen tube is -2 1+4× output gas oxygen flow (L/min).

However, the content of oxygen for medical use in the oxygen generator generally stipulates that the oxygen concentration is ≥90%(v/v), which means that when using the oxygen generator, the oxygen concentration will be lower than the corresponding value in the table. But if the oxygen concentration is lower than 25%, oxygen therapy has no therapeutic value; If the oxygen concentration is higher than 60% for more than 24 hours, poisoning will occur. Therefore, it is suggested to buy 2L-5L oxygen generator for home oxygen therapy, which can achieve the effect of adjuvant therapy.