Hermetic bags and other types of waterproof packaging are used to protect things, clothing and equipment from moisture. They fit valuable items: money, documents, mobile devices (tablet, phone), food, first aid kit, sleeping bag. They are used by hunters, fishermen, water tourists, ordinary tourists when hiking in rainy, snowy and wet weather.
According to the design features, two types of waterproof packaging are distinguished:
- with vertical loading — dry bag, dry bag;
- with horizontal loading — hermetic bag, hermetic bag.
There are also conical hermetic bags that are placed in the stern or bow compartment of the kayak.
- To ensure the tightness of the bag, it must be properly closed. After packing the items, let the air out of the bag and twist the neck (number of turns — at least 3).
- It is not recommended to wear a waterproof case with a mobile device or a card around your neck — this way you can easily lose valuables. It is better to wear a cover under a wetsuit or clothing. Herm with a walkie-talkie or telephone is fixed on the shoulder seam of the life jacket.
- Use the hermetic bag taking into account its weak points — folds, corners, kinks, seams. Choose models with multi-stitched and taped seams. Pay attention to the presence of a sealing tape covering the seam.
- It is better to stay on a hermetic bag with metal fittings, as the plastic one quickly fails.
- Hermetic bag
- Germ bag
Hermetic bag — completely protects the contents from water, has characteristic seals on the neck and fastex buckles. Occurs most often. Can be used as an insert in a bag or backpack.
Germ bag — differs from the hermetic bag by the presence of handles. This allows you to carry the bag on your shoulder and in your hand.
Germobaul — does not provide 100% protection of the cargo from water, but protects from splashes, dirt, rain. A popular solution among tourists and travelers.
Germoruzak — unlike a hermetic bag, it completely protects the contents from water and has straps that make it easier to carry (often removable). The hermetic backpack is characterized by large volumes.
Hermetic case – protects mobile devices and cards from water. Thanks to its transparency, this case makes it possible to work with the device in water.
Hermetic box / hermetic case — designed to store mobile devices and other equipment. Protects gadgets from water and mechanical damage, provides quick access to content, which is important when taking pictures. Medicines can also be placed in the hermetic box.
Compression bag — reduces the volume of contents by compressing them with special belts. It is often used to transport a sleeping bag and warm clothes — as a result, the volume of such products is significantly reduced. The compression bag frees up space in your backpack or car trunk.
- Waterproof compression bag — does not get wet, unlike the previous version. Minus — more weight than the compression model.
Important: experienced tourists and athletes often choose a dry bag for equipment and 2–3 dry bags equipped with compression bags, where shoes, thermal underwear, change of clothes are placed.
Many models of hermetic bags and hermetic cases are made of polyvinyl chloride (PVC) — durable and maintainable, but heavy and non-environmental material. There are products made of polyester — a less reliable, but lighter material.
Common hermetic bags polyurethane — durable, light, transparent, elastic material. Such models are resistant to temperature extremes. Marking — TPU (high temperature polyurethane, thermopolyurethane).
The materials of hermetic bags include nylon, which favorably differs from PVC in its low weight, compactness and increased thermal stability. The downside of nylon is the relatively lower strength.
Increasingly, there are models from carrington and “lamkotheka” – nylon coated with polyurethane (TPU nylon). These hermetic bags are resistant to UV rays and low temperatures, have all the advantages of conventional nylon. Products from “offender” — another variety of nylon — they are distinguished by increased strength and abrasion resistance, but they are quite heavy and expensive.
Material density — allows you to evaluate the strength and reliability of the hermetic bag. Measured in grams per square meter (g/m2). The denser the fabric, the stronger it is, but at the same time, its weight increases. Some PVC models have a density of 1000–1200 g/m2. But for most situations, a density of 450–600 g/m is sufficient.2. For nylon models, this parameter is lower — 150–300 g / m2.
Important: for a trip on a catamaran or raft, choose PVC or dense nylon dry bags, otherwise the lines and cords can damage the thin material.
Degree of tightness
Complete - the dry bag keeps the contents dry even afloat.
incomplete – the airtight bag provides protection only from dirt and splashes. Such bags are not suitable for kayaking or passing near waterfalls.
External dry pack – used as a stand-alone waterproof packaging.
Inner dry pack (liner) – fits into a backpack for maximum protection of the contents from getting wet. This option is useful during water travel or hiking in conditions of high humidity.
plastic clip — a plate with a locking mechanism. Used in packages for small items (documents, mobile devices).
Zip lock – is locked by twisting the upper edge of the hermetic bag and fixing the corners with a metal or plastic carabiner. It is found in volumetric hermetic bags. The lock exists in two versions — single and double (twisted 2–3 times, equipped with Velcro).
Depending on the model, the volume of waterproof packaging varies from 5 to 100 liters or more.
To choose the right dry bag in terms of volume, proceed from the number of things needed on the trip, the duration of the trip and the number of participants:
- 5 l — for dry clothes, a small sleeping bag, gadgets (for 1 person);
- 10 l — for the contents of a 5‑liter bag and a sleeping bag with synthetic insulation;
- 20 l — for clothes for a long hike and a thick winter sleeping bag;
- 30–40 l — for clothes for 2 people or for winter clothes for 1 person;
- 50–100 l and more — for the field kitchen, bivouac equipment.
When hiking, it is recommended to use several bags of a relatively small volume instead of one massive one. This will make it possible to sort items by purpose and type (food, clothing, equipment). This solution will prevent most things from getting wet if one of the hermetic bags is damaged.
Rings - made in the form of the letter “D”. They allow you to fix the dry bag on a kayak or boat, as well as connect it to other “herms”.
Important: do not thread a sling or cord under the neck fastener (“fastex”) to secure the bag on the vessel — this may break the buckle, and the contents of the “herm” will be in the water.
Valve - makes it possible to easily release air from the hermetic bag and thereby compress it to a minimum size. If there is no such valve, then “deflation” of the bag will require additional effort and skill.
transparent window — allows you to see the contents of the hermetic bag without opening it. Through such a window, you can use mobile devices — a phone, a navigator or a tablet.
loops - serve to fix the airtight bag to a kayak or catamaran. They are found in PVC products, often equipped with plastic fittings.