Last Updated on November 13, 2020 by Susheel Chandradhas
Silica Gel absorbs moisture in the air around your camera equipment (such a material is called an adsorbent). This ensures that the area is not friendly for fungus to grow inside your camera lenses. But did you know that if you leave silica gel inside your camera bag for too long it can get saturated with moisture and actually start to give off some of that moisture later on? This could really mess up your equipment. I didn’t know this myself, until a few years ago.
Here’s how you can avoid this potentially huge problem, and recharge / reuse Silica Gel sachets or crystals that you use to keep your camera equipment safe from moisture.
How Do I know When Silica Gel is Saturated with Moisture?
Indicating Silica Gel changes colour when it is saturated with moisture.
Normal Silica Gel is white, so it’s difficult to know when it is saturated with moisture. This is why I prefer to use Indicative Silica Gel. These Silica Gel crystals are blue when fully active, and become pink when they are saturated with moisture. There is also a variety that is orange when fully active, and that turn green when saturated. The orange type is preferred, as the chemical used to show moisture content may be less toxic.
Quick TIP: You can keep track of how humid any space is, by using a Digital Hygrometer. I highly recommend using one.
How Can I Restore or Recharge Silica Gel that is Saturated?
Silica Gel can be restored to its original state by heating it in an oven to 120 °C (248 °F) for 1–2 hours.
Silica Gel gets saturated with moisture rather quickly when there is a high level of humidity in the air. So, it’s important to check on the crystals / sachets often. Fully Saturated Silica Gel crystals can begin to give off humidity to the surrounding air when the humidity falls. This means that you need to refresh / recharge the crystals before they get saturated, so that they continue to absorb water from the air.
The good news is that you can reuse these Silica Gel Crystals many times, and the procedure is quite simple. All you need is an oven, an oven-safe dish, maybe some aluminium foil to hold the crystals, and you’re ready to recharge Silica Gel.
8 Steps to Reuse Silica Gel:
- Spread the crystals across the bottom of a bake-safe oven dish (you can use aluminium foil if you prefer to keep it off the dish itself). Spread them evenly and less than an inch deep in the dish.
- Place the dish in an oven and heat it to 120° C (248° F) for 1–2 hours until they start changing colour. If you want to avoid the risk of making your Silica Gel inactive, you could use a lower temperature and leave the Silica Gel in for a longer period of time.
- CAUTION: Do not heat Silica Gel to more than 180° C because it will lose its ability to absorb moisture, and destroy the indicating chemicals.
- The Silica Gel crystals will release the trapped water from within them, and will revert to their original blue or orange colour. Once the colour changes fully, the Silica Gel is recharged and restored to its original capacity.
- Note that the chemical that actually indicates the there is water in the silica gel crystals is a little more sensitive, and will most likely turn blue before the Silica Gel is fully refreshed. This is why we suggest leaving the crystals in the oven for a while longer, after the crystals turn blue / orange.
- Allow the crystals to cool down before you touch them, and then restore them to their perforated containers in your camera bag or cabinet.
- Store them in an airtight container so that they don’t absorb moisture from the atmosphere when they are not in use. Also, use an airtight storage container for your camera equipment so that humidity doesn’t come in from outside and saturate the Silica Gel crystals.
- Remember to recharge your Silica Gel crystals often enough, and your camera equipment should last a very long time.
Some people say that you can use a microwave oven to recharge Silica Gel, however we recommend against it because there is no way to control the temperature of the crystals, and you risk making them inactive.
How Many Times Can Silica Gel be Reused?
Silica Gel has been shown to be effective even after recharging it up to 500 times (PDF). Although, its efficiency decreases after about 100 uses, it is still quite efficient. Just remember not to heat it above 150°C or you may damage the indicating element.
Now That I’ve Recharged my Silica Gel Sachets, How Can I Reuse them?
Glad you asked! Silica Gel is useful around the house and office in more ways than to just keep your Camera Equipment safe. Here’s a short list.
- Keep some in your camera storage area, as well as your travel camera bags. They’re essential.
- Keep your paperwork or clothes free of mold in humid regions by putting sachets of Silica Gel in your folders.
- Quickly dry out electronic equipment if they get splashed. Of course, remember to it off before doing anything else. You can put your phone, or other device into an airtight container full of indicative Silica Gel crystals, or Sachets to get it dry super fast.
- Put some Silica Gel in with photo albums, when storing them, to prevent photos sticking to the cellophane pouches.
- Put Silica Gel sachets in your luggage, and especially in your Travel Pouch to keep the insides dry, and prevent your razors from rusting while you travel. This is especially useful when travelling to beaches and tropical climates.
- Keep some Silica Gel in your toolkit. This will keep the air dry and prevent rust.
- Every storage container needs a little Silica Gel.
- You can create art quicker by storing flowers and leaves with Silica Gel. This will dehydrate the flowers quickly, making for artistic subjects for your photography or art projects.
Frequently Aske Questions about Silica Gel for Photographers
What Type of Silica Gel Should I Buy?
You should buy indicative or reactive Silica Gel. Silica Gel comes in a few different forms. Typically they’re sold loose, as crystals, tiny spheres, or in porous plastic sachets that allow air through. I prefer to get the loose spheres or crystals because it’s not easy to see when the crystals are saturated when in sachets. More specifically, I prefer to buy indicative Silica Gel. This is also called reactive Silica Gel.
The sachets are very convenient for some non-photographic uses.
Is Silica Gel Toxic?
No, Silica Gel is not toxic. However, you should not try to ingest it, or mix it with edible items. Also keep it away from children, eyes, etc.
Here is some additional information though: The Cobalt Chloride used in blue>pink indicative Silica Gel has been classified as hazardous if inhaled or ingested, so if you’re using indicative Silica Gel, don’t inhale the dust from the crystals. The Orange > Green Silica Gel is considered safe for use.
Where Can I get Indicating Silica Gel?
- Here’s an Amazon.com page with various options.
- Dry-Packs 45gm Indicating Silica Gel Hard Plastic Canister (Orange > Green).
- 1 Gallon Blue Replacement Desiccant Indicating Silica Gel Beads.
Personally, I use orange beads of Silica Gel.
Thanks for reading right through to the end. Follow this link if you want more information about how to take care of your cameras when it’s raining, or if you live in a humid area.