How Do You Get Rid of Germs in Oxygen Not Included? A Comprehensive Guide

I remember my first colony in Oxygen Not Included, way back when I was just getting my feet wet with the game’s brutal, yet brilliant, complexities. Everything was going smoothly – or so I thought – until the dreaded “Food Poisoning” notification started popping up like dandelions in spring. My dupes were constantly running to the outhouses, productivity plummeted, and the air itself seemed to shimmer with a sickly green hue of contagion. It was a germ-infested nightmare, and I, like many new players, had absolutely no clue how to get rid of germs in Oxygen Not Included effectively. That early experience taught me a vital lesson: germ management isn’t just an afterthought; it’s a foundational pillar of sustainable colony design. Ignoring it is a sure path to an unhappy, unproductive, and eventually, a failed colony.

So, how do you tackle this pervasive threat? In Oxygen Not Included, getting rid of germs involves a meticulous, multi-faceted strategy that blends environmental control, material sterilization, smart infrastructure design, and careful duplicant management. You’ll employ everything from simple hand washing stations to complex chlorine gas chambers, temperature regulation, and clever gas flow dynamics to keep your colony pristine and your duplicants healthy. It’s about proactive prevention as much as reactive eradication, creating an environment where germs simply can’t thrive or spread.

Let’s dive deep into the fascinating, albeit sometimes disgusting, world of germ combat in ONI.

Understanding Germs: The Invisible Enemy

Before we can conquer germs, we need to understand them. In Oxygen Not Included, germs are microscopic nuisances that can severely impact your colony’s well-being. They’re not just a cosmetic effect; they have tangible, negative consequences for your duplicants and resources. The most common types you’ll encounter are:

• Food Poisoning: These nasty little guys cause Duplicants to frequently relieve themselves, leading to a vicious cycle of more contaminated water and more germs. They thrive in unhygienic environments, polluted water, and improperly stored food.
• Slime Lung: Predominantly found in the Slime biome, these germs cause Duplicants to cough, reducing their breath capacity and making them less efficient. They spread through polluted oxygen and often adhere to Slime and Polluted Dirt.
• Zombie Spores: The rarest and most dangerous, these can turn Duplicants into “Zombified” versions of themselves, which are uncontrollable and destructive. They’re typically found in specific, late-game biomes and require extreme caution.

Germs spread through almost every medium imaginable: air, water, food, surfaces, and directly from Duplicant to Duplicant. Their survival and multiplication are heavily influenced by environmental factors like temperature and the type of gas or liquid they reside in. For instance, most germs multiply rapidly at comfortable room temperatures (around 20-30°C / 68-86°F) and in polluted water or oxygen. Conversely, extreme heat, extreme cold, or exposure to certain gases like Chlorine can significantly slow their growth or outright kill them.

Prevention is Key: Stopping Germs Before They Start

The first and most crucial step in germ management is prevention. A well-designed colony minimizes germ exposure from the get-go, saving you a whole lot of headaches down the line.

Hygiene Stations: The First Line of Defense

Establishing proper hygiene routines for your duplicants is non-negotiable. These simple structures are your initial bulwark against germ proliferation.

• Hand Sanitizers: Place these strategically at the exits of all latrines, outhouses, and especially kitchens. Duplicants will automatically use them after interacting with unsanitary objects. Early-game sanitizers use Algae, so keep that in mind.
• Sinks: Once you’ve researched plumbing, sinks become your go-to. Hooked up to a fresh water supply and a drain, they are more efficient than sanitizers. Always ensure the water flows from the “clean” side to the “dirty” side of the room (e.g., washroom exit). This is called a “water lock” or “sink line” and forces dupes to wash up after using the facilities.
• Showers: While not directly for germ killing on hands, showers improve Duplicant morale and general cleanliness, contributing to overall well-being and potentially reducing the frequency of general germ pickup. They’re more of a comfort item, but a happy dupe is a healthy dupe.

Water Management: The Purity of Lifeblood

Contaminated water is a prime breeding ground for Food Poisoning germs. Managing your water cycles effectively is paramount.

• Closed-Loop Restroom Systems: Design your latrines and sinks to feed their “Polluted Water” output into a Water Sieve. The Sieve purifies the water, removing germs and converting it back into “Clean Water,” which can then be recirculated back into the hygiene stations. This creates a sustainable, germ-free water loop for your lavatories.
• Chlorine Gas Chambers for Water: For larger volumes of contaminated water (e.g., from polluted water vents or Slimelung-infected areas), a dedicated chlorine chamber is incredibly effective. Pump polluted water into a sealed room filled with chlorine gas. Chlorine slowly but surely kills all germs in the water. Once sterile, you can pump it out for use or further purification (e.g., desalinator if it’s salty).
• Liquid Shutoffs and Filters: Use these to prevent contaminated water from mixing with your clean supply. Building segregated plumbing networks for clean, polluted, and germy water is a best practice.

Food Safety: A Stomach’s Best Friend

Food Poisoning germs are, as the name suggests, often food-related. Protecting your food supply is critical.

• Sanitized Kitchens: Designate a clean area for food preparation. Ensure your cooking duplicants wash their hands before entering the kitchen. Keep the kitchen atmosphere free of polluted oxygen. Consider making it an airflow-controlled room, perhaps even with a small chlorine pocket near the food storage if you’re really worried.
• Refrigeration: Food spoils and attracts germs faster at higher temperatures. Use refrigerators to store all food. Refrigerator temperatures (typically below 4°C / 39°F) drastically slow down germ multiplication on food, and in a vacuum or chlorine environment, germs die off even quicker.
• Airtight Food Storage: While not directly killing germs, storing food in vacuum-sealed rooms (achievable by pumping out all gas) or rooms filled with sterile gas like Chlorine or Carbon Dioxide (which is denser than oxygen and sinks to the bottom, useful for floor storage) prevents airborne germs from contaminating it. Vacuum is the ultimate preservative for food and also instantly kills most germs on exposed surfaces.

Airflow and Gas Management: Breathing Easy

Airborne germs, especially Slime Lung, can be a major problem. Controlling your colony’s atmosphere is crucial.

• Air Filtration: Deodorizers convert Polluted Oxygen into clean Oxygen, simultaneously removing Slime Lung germs. Carbon Scrubbers remove Carbon Dioxide, which can indirectly help prevent germ buildup by maintaining a healthier atmosphere.
• Chlorine Gas Pockets: Chlorine gas is a potent germicide. Create small, sealed rooms or even strategically placed pockets of chlorine gas in areas where germs might accumulate or where items need sterilization. Due to its density, chlorine tends to sink, so it’s excellent for sterilizing items on the floor.
• Pressure Management: Use airlocks and gas pumps to control the flow of gases. Higher pressure in your clean zones can help prevent contaminated air from seeping in. Conversely, maintaining lower pressure in a dedicated germ-killing room can help pull in contaminated air for sterilization.

Active Eradication: Wiping Out Existing Germs

Despite your best preventative efforts, germs will inevitably appear. That’s when you need to deploy active eradication strategies.

Chlorine Gas: The Ultimate Germicide

If there’s one superstar in the fight against germs in Oxygen Not Included, it’s Chlorine gas. This element is lethal to almost all types of germs, making it an invaluable tool for sterilization.

Creating Chlorine Rooms and Locks

Dedicated chlorine chambers are your best friends. These are typically small, sealed rooms filled with chlorine gas. You can acquire chlorine from specific vents, geysers, or by distilling Brine. Once you have a source:

1. Build a Sealed Room: Construct a small, airtight room using insulated tiles if necessary to prevent temperature fluctuations.
2. Pump in Chlorine: Use gas pumps to fill the room with Chlorine gas. Aim for a pressure of 1800-2000g per tile for optimal effect.
3. Airlocks: Use two liquid locks or a series of regular airlocks to prevent the chlorine from escaping when Duplicants enter or exit. A common and effective setup is a “water lock” – a small depression in the floor filled with liquid (water or even crude oil) that blocks gas flow.

Decontaminating Materials with Chlorine

Chlorine rooms are fantastic for sterilizing various germ-ridden materials:

• Polluted Dirt and Slime: Store these materials in a chlorine room. The germs will slowly die off, making them safe to handle later. This is particularly useful for Slime, which off-gasses Polluted Oxygen that often carries Slime Lung germs. Off-gassing Slime in a chlorine atmosphere means any Polluted Oxygen created will immediately be sterilized.
• Contaminated Food: If you accidentally expose food to germs, placing it in a chlorine-filled refrigerator or vacuum-sealed chlorine room will sterilize it.
• Water/Liquids: As mentioned, a sealed tank or room filled with chlorine can sterilize large quantities of germy water.

Temperature Extremes: Freeze ’em or Fry ’em

While chlorine is a direct killer, extreme temperatures can also be highly effective at managing germ populations.

• Extreme Heat (Boiling): Raising the temperature of germ-laden liquids to boiling (over 100°C / 212°F) will rapidly kill most germs. This is particularly useful for contaminated water, where you can convert it to steam and then condense it back into clean, sterile water. Volcanic biomes or industrial heat sources can provide the necessary warmth.
• Extreme Cold (Freezing): Very low temperatures (below -18°C / 0°F for water, or even colder for other materials) can halt germ multiplication and eventually kill them, though the process is much slower than with heat or chlorine. Freezing food in an active cooling chamber is a good way to prevent germ growth and spoilage, even if it doesn’t instantly sterilize.

Water Sieve and Desalinator: Plumbing Purity

These two vital machines are workhorses for water purification, and a happy side effect is their germ-killing prowess.

• Water Sieve: This machine takes Polluted Water and converts it into Clean Water, simultaneously removing 100% of any germs present. It requires Sand or Regolith as a filter medium, so ensure a steady supply. This is the cornerstone of a germ-free bathroom loop.
• Desalinator: Similar to the Water Sieve, the Desalinator turns Brine or Salt Water into Clean Water, also removing all germs in the process. Essential for colonies near saltwater biomes or for processing saltwater geysers.

Duplicant Management and Health: Keeping Your Crew Healthy

Your duplicants are both the carriers and the victims of germs. Managing their exposure and health is a continuous task.

Monitoring Germ Exposure

Keep a close eye on the “germs” overlay (F4) to see where germs are accumulating and on your duplicants’ health panels to see their current germ count and immunity. Duplicants have an immunity stat; the higher it is, the longer they can resist falling ill, even when exposed to germs. Morale boosts and certain traits can affect immunity.

Med Bays: When Prevention Fails

Despite your best efforts, duplicants will occasionally get sick. That’s when the Med Bay comes into play. Build a Sick Bay with a Medical Cot and, if you have the resources, a Disease Clinic. Duplicants who are ill will rest here and receive treatment from other duplicants, speeding up their recovery. Ensure you have the necessary medical supplies, like Basic Medicine (from Wild Berries) or Advanced Medicine (from Pincha Peppernuts).

Atmo Suits: Personal Protection Equipment

For expeditions into germ-infested biomes like the Slime biome or areas with Zombie Spores, Atmo Suits are non-negotiable. These suits provide a sealed environment, preventing duplicants from inhaling contaminated air or picking up germs directly onto their bodies. A well-designed Atmo Suit dock with a decontamination airlock (often a chlorine room) will ensure duplicants are clean before re-entering the main base.

Scheduling: Hygiene Time

Make sure your duplicant schedule includes enough “Downtime” or “Sleep” blocks so they have ample opportunity to use hygiene facilities. A rushed schedule might mean they skip a hand wash, leading to germ spread.

Advanced Techniques and Considerations

For the seasoned colonist, there are always more sophisticated ways to optimize germ control.

Automated Decontamination: Smart and Efficient

Leverage automation to make your germ-fighting infrastructure even more effective:

• Smart Sensors: Connect germ sensors to gas pumps or liquid pumps. For instance, a germ sensor in a water tank can activate a pump to send germy water to a chlorine sterilization room when germ levels exceed a certain threshold.
• Automated Chlorine Loops: Design a system where chlorine gas is periodically pumped into a specific area (like an airlock or storage room) and then pumped out, creating an automated germ-killing cycle. This requires careful vent and pump placement along with automation wire logic.

Slime Biome Strategies: Taming the Goo

The Slime biome is a germ hotbed. Dealing with it requires specific tactics:

• Controlled Mining: Dig out Slime in small, manageable sections. Immediately store any extracted Slime or Polluted Dirt in a chlorine room or vacuum to prevent off-gassing Slime Lung germs.
• Chlorine Locks for Slime Biomes: Before entering a Slime biome, build a full-fledged Atmo Suit dock with a chlorine gas room. Duplicants enter the chlorine room, then the Atmo Suit, then the biome. Upon exit, they drop the suit, go through another chlorine shower, and then re-enter the base. This ensures no Slime Lung germs are carried in or out.
• Off-Gassing in Chlorine: Build a dedicated, isolated room filled with chlorine where you can dump large quantities of Slime. Any Polluted Oxygen off-gassed will be sterilized by the chlorine, and the Slime itself will slowly lose its germs.

Volcano/Geyser Germs: Heat Can Be a Problem

Sometimes, even high-temperature vents, like some Water Geysers, can output water with germs. In these cases, you might need to combine temperature-based sterilization with chlorine. For example, piping superheated, germy water into a radiator pipe system within a chlorine room can sterilize it as it cools.

Psychological Impact: Cleanliness for Morale

Don’t forget that a clean, germ-free base directly contributes to Duplicant morale. Nobody likes living in a petri dish! Good hygiene and a healthy environment mean fewer sick days, happier dupes, and ultimately, a more productive colony.

Common Pitfalls and How to Avoid Them

Even experienced players can make mistakes when it comes to germ control. Here are some common traps and how to steer clear of them:

• Neglecting Hygiene Early On: It’s tempting to focus on food and oxygen in the early game, but ignoring hygiene facilities will quickly lead to a spiraling germ problem. Build outhouses and hand sanitizers on day one!
• Cross-Contamination: Mixing plumbing lines, storing germy and clean items together, or allowing dupes to track germs from a polluted area directly into the kitchen are all recipes for disaster. Segregate your systems and pathways.
• Improperly Sized Chlorine Rooms: A chlorine room needs enough chlorine at sufficient pressure to be effective. Too small, or too little gas, and it won’t kill germs efficiently. Ensure your gas pumps are delivering enough.
• Ignoring Symptoms: Don’t wait until your entire colony is sick to address a germ problem. Keep an eye on the germ overlay and duplicant health notifications. Early intervention is key.
• Forgetting About Slime Lung in Polluted Oxygen: Polluted Oxygen off-gasses from many sources (polluted water, contaminated dirt). If it’s germy, those germs become airborne. Always filter Polluted Oxygen with Deodorizers, especially if it’s in your base.

Checklist for a Germ-Free Colony

To summarize, here’s a quick checklist to help you maintain a pristine and healthy base:

1. Early Game Hygiene: Build outhouses and hand sanitizers (or sinks) at the entrance/exit of your bathroom block immediately.
2. Closed-Loop Toilets: Implement a Water Sieve-based closed-loop system for your lavatories to sterilize polluted water.
3. Dedicated Kitchen: Create a clean, separate kitchen area with refrigerators, ideally with a hand washing station at the entrance.
4. Food Refrigeration: Store all food in refrigerators to slow germ growth and spoilage.
5. Chlorine Room for Materials: Construct at least one sealed chlorine room for sterilizing polluted dirt, slime, and any other germy materials.
6. Atmo Suit Docks: For ventures into hazardous biomes, equip your duplicants with Atmo Suits and design docks that include a chlorine decontamination step.
7. Water Sterilization: Have a plan for germy water sources, whether it’s a chlorine chamber, boiling, or simply routing it through a Water Sieve or Desalinator.
8. Air Quality Control: Use Deodorizers to clean up Polluted Oxygen, especially if it’s in your main base.
9. Germ Overlay Monitoring: Regularly check the F4 germ overlay and Duplicant health panels to catch germ issues early.
10. Med Bay Ready: Have a fully stocked Med Bay for when illnesses inevitably occur.

Frequently Asked Questions About Germs in Oxygen Not Included

Does boiling water kill germs in ONI?

Yes, absolutely. Boiling water is an incredibly effective method for killing germs in Oxygen Not Included. When water reaches its boiling point, typically above 100°C (212°F), almost all types of germs present in the water will be rapidly eradicated. This process often involves converting the germy water into steam, which is inherently sterile, and then condensing it back into clean liquid water.

This technique is particularly useful for large volumes of contaminated water, perhaps from a polluted water vent or a geyser that outputs germ-infested liquid. You can pipe the water into a chamber, heat it up using either direct heating elements or by running it through a heat exchange system with a volcanic biome, and then cool the resulting steam back into purified water. It’s a powerful late-game solution for ensuring a perfectly sterile water supply for your colony.

How do I deal with Slime Lung germs?

Dealing with Slime Lung germs requires a multi-pronged approach focused primarily on air quality and material handling. First and foremost, when mining in Slime biomes, ensure your Duplicants are wearing Atmo Suits to prevent them from inhaling Polluted Oxygen containing Slime Lung germs. Design your Atmo Suit docks with an airlock that ideally includes a pocket of chlorine gas to strip germs from the suit surface before entry into the main base.

Any Slime or Polluted Dirt collected from these biomes should be immediately placed into a dedicated, sealed room filled with chlorine gas. Chlorine gas will kill the Slime Lung germs on the material and any Polluted Oxygen off-gassed from the Slime. Within your base, Deodorizers are essential for converting any accidental Polluted Oxygen into clean Oxygen, simultaneously removing Slime Lung germs. Finally, proper base pressurization and segregated airflows can prevent germy air from spreading throughout your colony.

Can germs spread through pipes?

Yes, germs can absolutely spread through pipes in Oxygen Not Included, but only if the liquid or gas within the pipes is carrying those germs. The pipes themselves don’t generate or multiply germs, but they act as a conduit for germ-laden fluids. If you pump germy Polluted Water, for example, through a pipe, that water will remain germy until it passes through a purification step like a Water Sieve or Desalinator, or is exposed to germ-killing conditions like a chlorine chamber or extreme heat.

This is why it’s crucial to design segregated plumbing systems. Never directly connect a pipe carrying germy water to a clean water line without an intervening purification step. Always assume that whatever goes into a pipe will come out with the same germ status, unless a specific germ-killing process happens along the way.

Is freezing food enough to kill germs?

Freezing food is highly effective at *preventing* germs from multiplying and slowing down spoilage, but it’s generally not enough to *kill* all germs instantly or even rapidly. At freezing temperatures (typically below -18°C / 0°F), most germs enter a dormant state, and their growth stops. Over a very long period, some germs might die off due to the inhospitable conditions, but it’s not a quick sterilization method like exposure to chlorine or boiling temperatures.

For immediate and reliable sterilization, you’ll need to combine freezing with other methods, such as storing food in a vacuum-sealed room (which kills germs over time) or a chlorine-filled refrigerator. Freezing food is best thought of as a fantastic preservation technique that halts germ activity, rather than an active germ eradication strategy.

What’s the best way to clean up polluted dirt?

The most effective way to clean up polluted dirt and remove its associated germs (often Food Poisoning or Slime Lung if it off-gasses Polluted Oxygen) is to store it in a sealed room filled with chlorine gas. When polluted dirt is placed in a chlorine atmosphere, the chlorine will slowly but surely kill the germs on the dirt itself. If the polluted dirt is off-gassing Polluted Oxygen, any germs within that off-gassed oxygen will also be neutralized by the surrounding chlorine.

Alternatively, you can convert polluted dirt into clean dirt using a Compost, but this process itself can be a source of germy Polluted Oxygen if not managed in an isolated or deodorized environment. For immediate and complete sterilization of the material itself, the chlorine room method is generally preferred for its efficiency and thoroughness.

Mastering germ control in Oxygen Not Included isn’t just about constructing a few buildings; it’s about integrating these strategies into every aspect of your colony’s design. From the humble hand sanitizer to elaborate automated chlorine traps, a proactive and holistic approach will ensure your duplicants remain healthy, happy, and productive, allowing you to focus on the myriad other challenges this incredible game throws your way.