潔淨空氣量 (Clean Air Delivery Rate, CADR) 是衡量空氣清新機淨化能力的重要指標。CADR 值表示在固定時間內空氣清新機能夠去除的特定類型污染物的數量。選購時，我們應該確保比較不同型號的CADR值時，所測量的污染物類型是相同的。 此外，不同類型的污染物具有不同的淨化速度。一些空氣清新機在去除花粉和灰塵方面效果出色，而對於煙霧和異味的去除可能效果較差。因此，了解不同污染物的淨化速度與CADR值的關係是選購空氣清新機時的重要參考因素。  

空氣清新機的適用房間面積是另一個重要考慮因素。廠商通常會提供適用面積的計算方法，但不同廠商的計算方法可能有所不同。在比較不同型號時，我們應該注意廠商提供的計算方法是否一致，以避免產生誤導。 此外，污染程度也會影響空氣清新機的實際使用效果。如果房間的污染程度較高，則適用面積可能會有所減少。因此，在選購時，我們應該根據實際情況選擇適合的適用面積範圍。

空氣清新機的清淨方法也是重要的考慮因素之一。常見的清淨方法包括HEPA濾網、活性碳濾網、負離子和光觸媒等。 HEPA濾網是一種高效的過濾技術，能夠有效去除空氣中的微小顆粒，例如花粉、塵蟎和細菌等。活性碳濾網則主要用於去除異味和吸附有害氣體。負離子和光觸媒則通過產生負離子和利用光觸媒反應去除空氣中的污染物。 選購時，我們可以考慮空氣清新機是否搭配多種清淨方法，以提供更全面的淨化效果。  

噪音也是選購空氣清新機時需要考慮的因素之一。我們可以通過查看產品規格或詢問銷售人員來評估空氣清新機的噪音水平。同時，我們也應該注意選購時的一些細節，例如是否具有靜音模式或調節噪音水平的功能，以便在需要安靜環境時使用。

在選購空氣清新機時，我們應該比較不同型號的能源功率及其使用成本。不同型號的空氣清新機可能具有不同的能源效率，因此使用時的能源消耗也會有所不同。我們可以參考能源功率比較來選擇節能型的產品，同時根據自己的使用習慣估算每日的能源消耗。

空氣清新機通常具有各種功能，例如睡眠模式、Wi-Fi功能和自動感測空氣品質等。我們應該了解這些功能的實際應用場景以及它們是否符合我們的需求。例如，睡眠模式可以降低噪音並調節風速，適合在夜間使用，而Wi-Fi功能可以通過手機應用程式控制，提供更便利的操作方式。

在選購空氣清新機時，我們應該考慮配件的價格和壽命。不同型號的空氣清新機可能具有不同類型的過濾器，而過濾器的更換周期也會有所不同。我們應該查看廠商提供的建議更換建議，以了解更換過濾器的頻率和相應的成本。 同時，我們也應該了解如何正確清潔和保養空氣清新機，以確保其長期有效運作。廠商通常會提供清潔保養建議，我們應該按照指示進行清潔和保養，以延長產品的使用壽命。  

It is an important indicator for measuring the purification capability of an air purifier. CADR value represents the amount of specific types of pollutants that an air purifier can remove within a fixed time. When purchasing, we should ensure that the measured pollutants are the same when comparing CADR values of different models. In addition, different types of pollutants have different purification speeds. Some air purifiers excel in removing pollen and dust, while their effectiveness in removing smoke and odors may be lower. Therefore, understanding the relationship between the purification speed of different pollutants and CADR values is an important factor to consider when buying an air purifier. 

The suitable room size for an air purifier is another important consideration. Manufacturers usually provide calculation methods for the applicable area, but the calculation methods may vary among different manufacturers. When comparing different models, we should pay attention to whether the provided calculation methods are consistent to avoid misleading information. Additionally, the level of pollution will also affect the actual effectiveness of the air purifier. If the room has a higher level of pollution, the applicable area may be reduced. Therefore, when purchasing, we should choose the appropriate applicable area range based on the actual situation.

The purification methods of an air purifier are also important factors to consider. Common purification methods include HEPA filters, activated carbon filters, negative ions, and photocatalysts. HEPA filters are efficient filtration technology that can effectively remove fine particles in the air, such as pollen, dust mites, and bacteria. Activated carbon filters are primarily used to remove odors and adsorb harmful gases. Negative ions and photocatalysts remove pollutants from the air by generating negative ions and utilizing photocatalytic reactions. When purchasing, we can consider whether the air purifier is equipped with multiple purification methods to provide a more comprehensive purification effect.

Noise is also a factor to consider when purchasing an air purifier. We can evaluate the noise level of the air purifier by checking the product specifications or asking the salesperson. At the same time, we should also pay attention to some details during the purchase, such as whether it has a silent mode or the ability to adjust the noise level, for use in quiet environments when needed.

When purchasing an air purifier, we should compare the energy power of different models and their associated operating costs. Different models of air purifiers may have different energy efficiencies, resulting in varying energy consumption during use. We can refer to the energy power comparison to choose energy-saving products and estimate daily energy consumption based on our usage habits.

Air purifiers usually come with various features such as sleep mode, Wi-Fi capability, and automatic air quality sensing. We should understand the practical application scenarios of these features and assess whether they meet our needs. For example, sleep mode can reduce noise and adjust fan speed, making it suitable for nighttime use, while Wi-Fi capability allows control through a smartphone app, providing a more convenient operation method.

When purchasing an air purifier, we should consider the price and lifespan of accessories. Different models of air purifiers may have different types of filters, and the replacement cycles for filters may also vary. We should check the manufacturer's recommended replacement intervals and associated costs to understand the frequency of filter replacement and the corresponding expenses. Additionally, we should also learn how to properly clean and maintain the air purifier to ensure its long-term effective operation. Manufacturers usually provide cleaning and maintenance recommendations, and we should follow the instructions for cleaning and maintenance to extend the product's lifespan.