What to Store in Mylar Bags Besides Food (Emergency Uses)

Most people buy Mylar bags for rice and beans, then leave the rest of the pack sitting in a drawer.

That's a waste, because the same three properties that keep food fresh, a barrier against moisture, light, and air, protect a lot of other things you'd want intact after a flood, a storm, or a long power outage.

Here's what actually belongs in a Mylar bag besides food, what doesn't, and how to build an emergency kit around them.

Why Mylar Works for Non-Food Items

A Mylar bag is three bonded layers with aluminium foil in the middle. That foil blocks moisture, light, and oxygen almost completely, which is why food lasts decades inside one.

Those same properties matter for emergency gear. Moisture is what ruins most supplies in a disaster, water damage to documents, corrosion on electronics and batteries, degraded medications.

A sealed Mylar bag is one of the cheapest, lightest barriers you can put between your supplies and that damage. Our guide on what Mylar bags are made of covers the material in detail.

One important distinction before we go further: for non-food items, use silica gel desiccant, not oxygen absorbers. Oxygen absorbers remove oxygen, which matters for food spoilage. For documents, electronics, and tools, moisture is the enemy, and silica gel is what handles it.

What To Store in Mylar Bags (Other Than Food)

Here’s a complete list of items you can store in emergency cases:

1.     Documents, ID, and Cash

The most valuable thing you can seal in a Mylar bag has nothing to do with food.

Passports, birth certificates, insurance policies, property deeds, medical records, and emergency cash all become useless when they're soaked. In a flood or a burst pipe, paper is the first casualty and the hardest thing to replace.

Seal them flat in a quart bag with a silica gel packet, heat-seal the top, and store the bag somewhere you can grab it quickly. Photograph or scan everything first and keep a digital copy separately, the sealed bag is your physical backup, not your only copy.

2.     First Aid and Medical Supplies

Bandages, gauze, antiseptic wipes, and medications all degrade faster in humid conditions, and a first aid kit that's been sitting in a damp garage for three years may not be sterile when you need it.

Sealing medical supplies in Mylar keeps them dry, clean, and organised. Group them by function, wound care in one bag, medications in another, so you're not tearing open every bag looking for one item.

Check expiry dates on anything sealed. The bag protects against moisture, not time. Medications still expire on schedule, so rotate them the same way you would on a shelf.

3.     Electronics, Batteries, and Communication Gear

Radios, chargers, power banks, spare batteries, and backup phones are exactly the gear you need in an outage and exactly what corrosion destroys. Battery terminals oxidise, connectors corrode, and moisture creeps into anything with a port.

Seal them with a silica gel packet, never an oxygen absorber. The desiccant pulls residual humidity out of the bag and keeps the contents dry through seasons of temperature swings.

Batteries especially. A sealed bag of spare AAs stored in a dry state will still hold charge years later, where the same batteries loose in a drawer corrode at the terminals.

4.     Hygiene and Sanitation Supplies

Soap, wipes, toothpaste, toilet paper, and feminine hygiene products are easy to overlook and miserable to go without. They're also bulky and vulnerable to damp.

Compressed into sealed Mylar bags, they stay clean, dry, and compact, which matters if the kit is going in a car trunk or a bug-out bag rather than a closet.

5.     Seeds for Planting

This is the long-term play most people miss. Properly dried seeds sealed in Mylar stay viable for years, far longer than in a paper packet in a shed.

The requirements are specific: seeds must be completely dry before sealing, and you use a silica gel packet rather than an oxygen absorber, since seeds are living tissue and need to stay dry rather than oxygen-free. Store them cool and dark.

A quart or half-pint bag holds a season's worth of most varieties. For a longer-term seed bank, portion by variety and label clearly.

6.     Pet Supplies

Easy to forget when building a kit. Pet food, medications, and a spare collar or leash all seal well and take up little space.

Dry pet food follows the same rules as human food, it's a dry good with some fat content, so expect shorter shelf life than rice but far longer than the original bag.

Our list of foods that store well in Mylar covers the fat-content principle that applies here too.

7.     Tools and Metal Gear

Anything that rusts benefits from a sealed dry environment. Multi-tools, knives, fishing gear, spare parts, ammunition, and hand tools all store well in Mylar with a desiccant packet.

Wipe metal items with a light oil before sealing for extra corrosion protection, then seal with silica gel. The combination keeps tools functional through years of storage in a shed or garage where humidity swings constantly.

What Not to Store in Mylar Bags

Honest limitations, because the wrong use is worse than no use:

• Water. Mylar bags aren't built to hold liquid weight, and a failed seam means a wet kit and no water. Use proper water containers.
• Anything you need to see quickly. Mylar is opaque by design. Label every bag clearly or you'll be cutting open three to find one thing.
• Items that need airflow. Anything damp or organic that isn't fully dry will grow mould in a sealed bag.
• As a substitute for an emergency blanket. Mylar blankets are a different product built for heat reflection. A food storage bag isn't one.

Building a Modular Emergency Kit

The advantage of Mylar over one big sealed container is that you can open one category without exposing everything else.

Group by function:

• Documents and cash
• First aid and medications
• Electronics, batteries, and cables
• Hygiene and sanitation
• Pet supplies
• Tools and repair items

Label every bag with contents and a review date. Colour-coded labels or tags make grabbing the right one fast under pressure.

Store copies in multiple locations. A kit at home, a smaller one in the car, and a minimal one at work covers you regardless of where you are when something happens.

Review twice a year. Check expiry dates on medications and food, confirm batteries hold charge, and reseal anything you've opened.

Our sealing guide covers resealing a bag you've cut open, seal high the first time and you can reseal several times.

Final Verdict

Mylar bags earn their place in an emergency kit for the same reason they work for food: they keep moisture, light, and air away from things that degrade. Documents, medications, electronics, seeds, and tools all last longer sealed than loose.

Use silica gel rather than oxygen absorbers for non-food items, seal everything fully dry, label clearly, and review the kit twice a year.

Roylo Globe's mylar storage bags work equally well for emergency supplies, with sizes from quart pouches for documents and seeds up to 5-gallon bags for bulk gear.

Frequently Asked Questions

What can you store in Mylar bags besides food?

Documents, cash, first aid supplies, medications, electronics, batteries, hygiene items, garden seeds, pet supplies, and metal tools. Anything that degrades from moisture, light, or air exposure benefits from a sealed Mylar bag.

Do you use oxygen absorbers for non-food items in Mylar bags?

No. Use silica gel desiccant instead. Oxygen absorbers target food spoilage, while moisture is the main threat to documents, electronics, and tools. Desiccant is the right tool for those.

Can you store electronics in Mylar bags?

Yes, with a silica gel packet. Mylar blocks moisture that corrodes battery terminals and connectors, making it useful for radios, chargers, power banks, and spare batteries in an emergency kit.

Can Mylar bags hold water?

No. They're not designed for liquid weight and the seams can fail. Use purpose-built water containers for emergency water storage.

How long do seeds last in Mylar bags?

Properly dried seeds sealed with a silica gel packet and stored cool and dark stay viable for several years, far longer than in paper packets. Seeds must be completely dry before sealing.