Can down sleeping bags be washed in a washing machine? No. When a down sleeping bag is spun-dried, it traps a large amount of gas that cannot escape. When the pressure exceeds the limit, a phenomenon similar to an "explosion" may occur, which is highly dangerous. For this reason, some washing machine instruction manuals clearly state that down sleeping bags should not be washed in them.

In addition, a wet down sleeping bag holds a significant amount of water. Moreover, the outer layer of some down sleeping bags is coated with a waterproof material. This makes it difficult for water to be spun out, causing the down sleeping bag to become even heavier and bulkier. If the sleeping bag is placed unevenly in the spin drum, it is very likely to cause the drum to spin crookedly, which may further crack the washing machine’s outer casing.

How to Clean Oil Stains on a Down Sleeping Bag?

Dip a towel in gasoline and gently wipe oil-stained areas such as the neckline, cuffs, and front placket. After the oil stain is removed, use a dry towel to wipe the areas that came into contact with gasoline. Once the gasoline has completely evaporated, the sleeping bag can be used again.

Analysis of Down Sleeping Bag Knowledge

The most common fillings in down sleeping bags are goose down and duck down. Both types can be further categorized by color into white down and grey down. Based on market prices, the order from highest to lowest is: white goose down > grey goose down > white duck down > grey duck down. Influenced by this price ranking, many people mistakenly assume the quality follows the same order—but this is not the case. Through theoretical research and practical experience with down, color has little to do with the quality of a down sleeping bag.

As for why white down is more expensive, there are two main reasons. First, white down looks better than grey down: it does not show through the fabric, whether the fabric is light-colored or dark-colored. In contrast, grey down is more restrictive—it can only be used in dark-colored fabrics. White down’s light color makes it suitable for a wider range of fabric colors. Second, the fiber structure of white down plays a role: its fibers are relatively thinner, softer, and longer. Longer fibers result in better loft, making the sleeping bag easier to retain heat. Generally, larger and more mature birds produce higher-quality down, which suggests goose down may be superior. While the production processes for goose down and duck down are the same, goose down outperforms duck down in terms of quality, loft, and warmth retention. The most important reason goose down is more expensive than duck down, however, is its much lower yield: goose down can only be harvested once a year, whereas duck down can be harvested up to three times a year.

2. Down Content

Down content refers to the percentage of fine down clusters in the total filling of the sleeping bag. For example, if a down sleeping bag’s filling consists of 90% white duck down and 10% white feathers, its down content is 90%—making it a high-specification down sleeping bag. When you decide to buy a down sleeping bag, be sure to check the product label attached to the collar first. If the down content is less than 50%, you should be cautious: it no longer meets the minimum standard set by the state. A down sleeping bag with high down content feels soft to the touch; more feather shafts indicate lower quality.

3. Fill Weight

It is important to note that fill weight is different from down content. Down content is expressed as a percentage, while fill weight refers to the actual weight (in grams) of the total filling (feathers + down) in the sleeping bag. It is related to factors such as the sleeping bag’s size, length, and style. Some people prefer to buy down sleeping bags with a higher fill weight when shopping, thinking that a thicker filling means better warmth. However, you should never underestimate down content—because the fine down clusters themselves play a crucial role in retaining heat.

4. Loft

Loft is an important international indicator for measuring the warmth retention of down. It refers to the volume (in cubic inches) occupied by one ounce (30 grams) of down under specific conditions. For example, if one ounce of down takes up 600 cubic inches of space, the loft of that down is 600. There is a common saying: fill weight and down content represent the "quantity" of the down, while loft determines the "quality" of the down. When fill weights are similar, higher loft means better warmth retention.