Pharmacies
Pharmacy: duct humidity and medicine storage
The pharmacist watches expiry dates and the cold chain. The humidity of the shop counts too, and the air conditioning governs it.
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A duct or pan in poor condition can leave the humidity of the sales area and storeroom higher and more variable than the unit indicates. For a pharmacy in Panama what is useful is to measure humidity, check the pan, coil and first section with a camera, and record the results. Cleaning is proposed only if the camera shows a condition that justifies it.
The pharmacy opens at seven and by mid-morning the pharmacist has noticed that the cardboard boxes in the storeroom are softer than usual. The blister packs, well sealed, do not seem affected, but a supplier receipt got damp on the counter. Someone says it is the rain. Another says it is the air conditioning.
The doubt is valid and has a less dramatic answer than it seems. The condition of the ducts and the condensate pan influences the humidity of the shop, and humidity is one of the factors that medicine labels ask to control. What follows is how things connect and what can be done.
What do labels and standards ask about humidity?
Executive Decree 197 of 2009 of MINSA classifies Panama as a very humid tropical country and places it in climatic zone IVb, with stability study conditions of 30 °C and 75% relative humidity. Those are the conditions under which medicines are tested, not a storage limit for pharmacies. It means manufacturers design the product to withstand Panama’s climate, but not that humidity stops mattering.
To coordinate a visit related to pharmacies, Climatiza answers inquiries and confirms availability according to the schedule of the place.
The WHO guide on storage and transport of pharmaceutical products, in annex 9 of technical report 961, asks for humidity control for products labeled “store in a dry place” and air handlers with continuous power where possible. It also describes sensors with half-degree accuracy, at least six readings per hour and a manual check twice a day. That structure of measuring, recording and reviewing is what carries the topic over to a specific pharmacy.
How does a dirty duct alter the humidity of the shop?
In three ways. A condensate pan with residue or a partly blocked drain evaporates some of the water back into the airstream. A coil covered in dust cools worse and dehumidifies less. And a porous lining that holds water returns humidity to the air when the unit switches off and the duct warms. The result is a pharmacy at 22 degrees with humidity rising, even though the thermostat reads right.
Solid medicines are sensitive to swings more than to a fixed value. A study of tablets with acetylsalicylic acid exposed to humidity cycles between 53% and 75% found that the effect depended on excipients and on the product’s humidity history (Natali and colleagues, 2022, Molecular Pharmaceutics). It does not say that a pharmacy should worry about every oscillation, but it does say that variability matters on top of the average, and a system with humidity going up and down contributes to that variability.
What happens in the medicine storeroom?
The storeroom is the point to watch because it has less air movement, more cardboard boxes and less daily attention than the sales area. If it shares a system with the shop, it receives the same humidity but without the ventilation of the door and the customers. If it has its own unit, it is usually smaller and less checked. In both cases a recording thermo-hygrometer and a more frequent check of the grille and filter are advisable.
When the humidity of the storeroom rises, the first symptom is soft cardboard and smell. Before blaming the climate, the unit is looked at: filter, pan, drain and the first section of the supply. The EPA guidance on mold in commercial buildings recommends keeping humidity below 60% and checking that drip pans are clean and drain freely. That reference is a starting point for the shop, and the specific limit of a product is set by its label.
Why does it matter and what evidence is there about the duct?
It matters for the product, for order and for inspection. A shop that can show a humidity record and system upkeep responds better to a control visit and to a question from a supplier or a customer. It also matters for comfort, because a humid shop feels worse and smells worse.
It is worth being clear about what cleaning does not do. The EPA and the CDC state that duct cleaning has not been shown to prevent health problems, and it is not framed here as protection for medicines either. It is upkeep of the system that regulates humidity, and it is decided with what the camera shows.
What is the visit like and what is recorded?
The visit begins with a humidity reading in the sales area and the storeroom, at the same hour on two different days if possible. Then the air handler is opened to see the pan and the coil, and the camera runs through the first section of the supply and the return. Photos are taken and the state of the drain is noted. The approach to work in a shop of this kind is explained in how the work is organized in a pharmacy, and the camera method in the camera inspection.
An illustrative case, not a real client: a pharmacy with a central unit and a storeroom at the back. The humidity of the sales area stays stable, but in the storeroom it rises in the afternoons. The camera shows the pan with residue and the drain half blocked, and the first supply section with damp dust. The sensible decision is to clean the pan, free the drain, treat that section and measure humidity again. If it drops and stabilizes, nothing more is needed.
- Humidity readings of the sales area and the storeroom, with date and time.
- Photos of the pan, the coil and the first section of the supply.
- Condition of the drain and the duct lining.
- One recommendation per run: clean, monitor or no action.
- A note for the shop's record that can be shown on a control visit.
With that record the shop decides on evidence and orders its calendar with the criteria for when to clean. When the business shares a building with a clinic, the logic of a health center with its own protocols applies only to what belongs to the shop.
For a first conversation about the system, the contact details are on the Climatiza site and the method is described on its duct cleaning service page.
Sources
On this site
- Pharmacies and laboratoriesHow the work is organized in this sector
- Hospitals and clinicsA neighboring sector
- Camera inspectionThe real condition before deciding
Climatiza and Radar Panamá
Why does inspecting and cleaning ducts matter?
These are the technical reasons, with their source, why the condition of the ducts is checked before deciding. Duct cleaning has not been shown to prevent health problems according to the EPA and the CDC, and it is proposed only when the observed condition justifies it.
| Advantage | Data with source | What it means in practice |
|---|---|---|
| Require method and a report from the provider | NADCA published in 2025 the current edition of its ACR standard on assessment, cleaning and restoration of air systems. | It is an industry reference and not a seal: it helps ask for method, photographs and scope in writing. |
| Know whether cleaning is needed before deciding | The EPA states in its duct cleaning guide that cleaning is justified for visible mold, pests or a notable buildup of dust and debris. | A camera inspection documents the condition and allows a decision based on evidence, without unnecessary work. |
| Protect equipment performance | In a laboratory test with dust equivalent to one year of use, coil pressure drop rose between 6 and 30 % and efficiency (EER) fell between 1 and 9 % (Yang, Braun and Groll, ARTI, 2004). | It is a laboratory result and not a promise of savings: it points to the components worth checking. |
| A local figure that changes the decision | Executive Decree 197 of 2009 from the Ministry of Health recognizes Panama as a very humid tropical country and adopts climate zone IVb for medicine stability studies, which uses 30 °C with a 2 °C tolerance and 75% relative humidity with a 5% tolerance. These are the conditions of those studies and not a storage limit for pharmacies. (MINSA, Executive Decree 197 of 2009). | It is the sector context taken into account when planning the visit. |
Frequently asked questions
Are shelf medicines damaged by the humidity of the shop?
Manufacturers test them in tropical conditions, but the label sets the limits and humidity swings matter. That is why humidity is measured, the system is checked and a record is kept, without assuming every product reacts the same.
Can a dirty duct raise the humidity of the shop?
Yes, indirectly. A pan with residue, a partly blocked drain or a damp porous lining return water to the air. The camera confirms whether those points are affected and helps decide what to clean or correct.
What record is worth keeping in a pharmacy?
Humidity readings with date and time, photos of the system condition and a note of what was done and what remains under watch. What is required is defined by each authority and each supplier, and the record organizes the reply.
How should temperature and humidity be measured on a pharmacy shelf?
With calibrated sensors placed at product height and frequent logging. The WHO (2011), in its annex on storage, recommends sensors accurate to ±0.5 °C and a manual review of the records twice a day. A single wall thermometer does not represent what happens on the shelf itself.
What happens to medicines if the pharmacy air conditioning stops?
Room temperature and humidity climb quickly, and products are exposed to conditions different from those on their label. The WHO (2011) recommends uninterrupted power for air conditioning where possible. The deviation is recorded and the manufacturer is consulted about what to do with the stock.
Keep reading the guide
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Do you want to know the condition of your system?
A camera inspection lets you see the inside of the ducts before deciding what to do. Message us and we will confirm availability.
- +507 6388-2083
- info@climatizapanama.com
- Calle Gervasio García, 8, Panama City