It’s Spring! The grass is green, the trees are leafy, and the flowers are quite pretty. This however, brings with it an air quality problem: pollen. The HVAC solution to pollen is to maintain positive pressure in the building, good filtration, and implement some good cleaning practices. That however, is not what we’re talking about today. We’re talking about the science of pollen and why we have pollen allergies, because few HVAC Blogs look at this type of science, but we do.
Most complex life on Earth needs two organisms to reproduce. You have two parents, your dog had two parents, and the tree in your front yard, probably had two parents. The thing is though, trees and flowers can’t walk up to each other to reproduce, they’re just static-things that shift in the breeze. Something has to move genetic material from one plant to the other.
Pollen is how plants reproduce. They’re hardy cells that get carried off into the wind in such vast quantities that they’re all but guaranteed to swarm a compatible plant. These cells contain that tree’s genetic material and they’re designed to mix with another plant to produce seeds that will eventually grow into another plant.
This is an ongoing process, but it’s worse in the Spring when plants are bursting back to life after a long, dormant winter. Varying weather conditions will cause days with more or less pollen. After a period of prolonged rain, pollen counts tend to be lower as the pollen is literally hammered out of the sky by an onslaught of rain. During the Fall and Winter the process reduces or stops entirely. Plants really can’t reproduce when it’s freezing out. Winter is a break for those with allergies.
The Human Immune Response
Unfortunately, pollen goes everywhere and there’s a lot of it. You can’t avoid it. Those fine particles will wedge in your shirt, on your skin, and in your nose. Shy of wearing a hazmat suit outdoors, exposure is near guaranteed. That’s where things get interesting.
Our immune system reacts to foreign invaders. An immune cell like a B-Cell will encounter something in your body. It’ll decide if that thing is a threat or some inert piece of matter. If your body decides it’s a threat, it produces antibodies which bind against the threat. Antibodies are essentially microscopic tags, they chemically adhere to the surface of different cells and viruses. These identify the intruder to other cells in the body and can disrupt the action of viruses, toxins, and bacteria.
The problems start when the antibodies find something to attack. They trigger the other immune cells in your body to also attack. This is microscopic, chemical warfare. The immune cells release histamines and cytokines, chemicals which will destroy the pollen, but they’re also going to disrupt some of your own cells, leading to swelling, nasal discharge, watery eyes, pain, and all the rest of those lovely struggles..
These problems don’t occur for everyone, and science has only a few guesses about why that is. The first major part is exposure. Your immune system ‘learns’ from being exposed to things. If your country commonly has a specific family of the cold virus, you build up resistance to it. When someone from outside the region shows up, their immune system has never encountered that particular cold variant, and it has no defenses. It hits them harder. This is in part why you may get sick after traveling abroad: exposure to new diseases. If you’re exposed to pollen while you’re young, your body will likely learn it’s harmless and not produce antibodies. If you grew up in a house more like a clean room and rarely went outside, yoru body probably things pollen is the plague. Secondarily, there are genetic factors that control your immune system and make it more or less susceptible to these types of problems.
What To Do About This
Pollen allergies only effect about 1/10th of the population, so there’s a good chance if you’re reading this, you don’t have first-hand experience with how awful allergies are. In simplest terms, it’s like having a cold that comes and goes nearly at random. You walk outside and get hammered by the pollen, within minutes your head is pounding with a sinus headache. Your eyes water and the only thing you want to do is go inside and try to rest. Anything triggering the immune system is going to be incredibly tiring.
The medications for allergies are arguably worse than the disease themselves. You’re modifying how the immune system reacts, so they can cause drowsiness, fatigue, and pains all their own. It’s not always viable to load up on antihistamines for the season.
As a business owner at any scale, you should take precautions to ensure your guests and employees have a comfortable working environment. Ensure your facility has dust mats at all entrances to catch pollen on people’s shoes. Ensure every liter of air inside is filtered. Change your filters regularly. Clean your floors and vertical surfaces as you would to handle any other air-quality issue. And try to keep positive pressure inside the facility so no outside particles are sucked in.