★ SOSA · clinics, polyclinics & medical centres
Count the volumes a door closes, not the square feet on the brochure. In most clinics that removes forty to sixty per cent of the plan area
★ ★ ★ ★ ★
★★★★★
"We were sizing for 6,000 sq ft. Once the clinical rooms came out of the calculation we were sizing for about half that, and bought one machine instead of two."
One instead of two
★★★★★
"The arithmetic was shown to us rather than done for us. Area divided by 10.76, times ceiling height. I have used it twice since."
Shown the sum
★★★★★
"Double-height atrium doubled the volume under the footprint, which is obvious once said and was not obvious before."
Atrium volume
★★★★★
"Three floors, three specialities, three machines, one scent. Consistency was the requirement and it was met simply."
Three units, one scent
★★★★★
"We went to the Aangan because we had an AHU to tie into. We were told the Vaayu would have been wrong for us and why."
Aangan · HVAC tie-in
★★★★★
"The noise question was real. A consultation cabin two metres away hears the air conditioning and not the diffuser."
Under 38 dB
★★★★★
"We were sizing for 6,000 sq ft. Once the clinical rooms came out of the calculation we were sizing for about half that, and bought one machine instead of two."
One instead of two
★★★★★
"The arithmetic was shown to us rather than done for us. Area divided by 10.76, times ceiling height. I have used it twice since."
Shown the sum
★★★★★
"Double-height atrium doubled the volume under the footprint, which is obvious once said and was not obvious before."
Atrium volume
★★★★★
"Three floors, three specialities, three machines, one scent. Consistency was the requirement and it was met simply."
Three units, one scent
★★★★★
"We went to the Aangan because we had an AHU to tie into. We were told the Vaayu would have been wrong for us and why."
Aangan · HVAC tie-in
★★★★★
"The noise question was real. A consultation cabin two metres away hears the air conditioning and not the diffuser."
Under 38 dB
★ ★ SOSA Vaayu — waterless, timed, key-locked ₹11,999 SOSA Aangan — up to 3,000 m³, HVAC-ready ₹25,999
✓ Aangan ₹25,999 · up to 3,000 m³ (≈8,000–10,000 sq ft) · HVAC or standalone ✓ Vaayu ₹11,999 · up to 1000 m³ · one machine per public volume, not per floor plan ✓ Count the volumes a door closes. Clinical rooms come out of the sum entirely
Founder Diaries · Clinics & Medical Centres · HVAC Tie-In or Standalone Units
The test that decides it: does the duct serving reception, the waiting hall and the corridors serve anything clinical? If yes, the HVAC scheme is over — not negotiable, not solvable with a damper somebody promises to shut. If no, and the volume is large enough to need it, the Aangan at ₹25,999 ties into the AHU.
The common outcome: splits throughout, so one or two Vaayu units at ₹11,999 each, freestanding or wall-mounted in the public zones, on a timer, on low, key-locked. Up to 1000 m³ each, 400ml lasting about seventy-five days, under 38 dB. Clinical rooms fragrance-free with their doors shut. Housekeeping and presentation, no clinical claim of any kind.
Vaayu · standalone or duct-mounted₹11,999Shop → Aangan · HVAC or standalone₹25,999Shop → 
Vaayu · wall mount₹11,999Shop →
This is not a preference question and it is not a budget question. It is a survey question, and most clinics can settle it in twenty minutes with a torch, a ladder and the air-conditioning drawings. An HVAC tie-in only makes sense where a ducted central system genuinely serves the public zones — and a great many Indian clinics do not have one at all. They run wall-mounted and cassette splits, one unit per room, with no common supply duct anywhere in the building, and for those facilities an HVAC scheme is not a thing you can buy at any price. Where a central duct does exist there is a second test, and it stops more schemes than the first: if that same supply also feeds a consultation room, a laboratory or a sample-collection room, you cannot use it. A door can be closed. A supply grille cannot. If the supply to your public zones cannot be separated from the supply to your clinical zones, standalone units are not the compromise — they are the correct answer, and the Vaayu at ₹11,999 is the machine that does it.
Quick answers — read this first
Free, and do it before you ask anyone for a quotation: establish what system you actually have. Stand under every grille in the public areas and look at it. A cassette with a return grille in the same square is a split serving that room only. A linear slot or a louvred grille with no return beside it is fed from a duct, and a duct comes from somewhere. Open the ceiling at the nearest access panel and follow it. Get the AC drawings from whoever did your fit-out. Then write down one sentence: our public zones are served by ______, which also serves ______.The test that decides it: does the duct serving reception, the waiting hall and the corridors serve anything clinical? If yes, the HVAC scheme is over — not negotiable, not solvable with a damper somebody promises to shut. If no, and the volume is large enough to need it, the Aangan at ₹25,999 ties into the AHU.
The common outcome: splits throughout, so one or two Vaayu units at ₹11,999 each, freestanding or wall-mounted in the public zones, on a timer, on low, key-locked. Up to 1000 m³ each, 400ml lasting about seventy-five days, under 38 dB. Clinical rooms fragrance-free with their doors shut. Housekeeping and presentation, no clinical claim of any kind.
The short answer
Short answer: connect to HVAC only where a ducted central system serves the public zones and nothing clinical. Most Indian clinics run split units room by room and therefore have no HVAC option at all, which makes standalone the correct answer rather than a compromise. Where a duct does exist, trace what else it serves before costing anything: if the same supply reaches a consultation room, a laboratory, a dispensing counter or a sample-collection room, the scheme is finished, because a supply grille cannot be shut like a door. Vaayu Rs 11,999 standalone or wall-mounted, Aangan Rs 25,999 where a genuine tie-in exists.
The survey, and why it is free: walk the public areas and identify every grille as either a split serving one room or a terminal on a duct. Get the fit-out drawings. Ask your AMC vendor which AHU serves which zone, because they already know. Then do the volume sum - square feet divided by 10.76, multiplied by ceiling height in metres, counting only the volumes a door closes - because a building under 1000 m3 of public volume does not need an AHU tie-in even when one is available.
The two machines, costed: Vaayu Rs 11,999 - waterless cold-air nebulisation, no standing water tank, up to 1000 m3 or roughly 2,000-3,000 sq ft, 400ml lasting about 75 days, app plus 1h/4h/8h/24h timers, under 38 dB, 0.9 kg at 165 x 80.5 x 215 mm, freestanding, wall-mounted or duct-mounted, auto-stop and key-lock. Aangan Rs 25,999 - HVAC-connected or standalone, up to 3,000 m3 or roughly 8,000-10,000 sq ft, 800ml reservoir, metal body, programmable, under 42 dB. Free shipping above Rs 499.
In this guide
No central duct, which is most clinics
Vaayu · ₹11,999 standalone
A ducted AHU serving public zones only
Aangan · ₹25,999
The survey, before either of them
Twenty minutes · ₹0
Straight answer
Should a medical centre connect scenting to its HVAC, or use standalone units?
1. First establish whether you have an HVAC system at all, because the word is used very loosely. A building with twelve cassette units and four hi-wall splits does not have HVAC in the sense this question means. It has sixteen independent room coolers, each recirculating the air of the room it sits in, with no common duct between them and nothing to tie into. A building with a ducted air-handling unit in a plant room, supply ducting in the ceiling void and return paths back to a filter box does. A building with ductable split units — an indoor unit above the false ceiling with a short duct run to two or three grilles — is a third case, and it is the one that causes the most confused conversations, because it looks ducted from below and behaves like a split.
2. If you have splits, the answer is standalone and there is nothing further to decide. This is the commonest situation in Indian clinics and polyclinics by a wide margin, and it is not a disadvantage. A standalone Vaayu at ₹11,999 sitting in the reception zone covers up to 1000 m³, which in practice is most of the public volume of a 2,000 to 3,000 sq ft facility. It needs a socket and a shelf. It does not need a contractor, a shutdown, a damper or a conversation with your AMC vendor.
3. If you do have a ducted AHU, trace what it serves before you cost anything. This is the test that matters and it is the one most suppliers skip. Get the drawings, and if there are no drawings, ask the AMC vendor, who will know which AHU feeds which zone because they change the filters. Then write down every room on that AHU. If the list includes a consultation room, an examination room, a treatment or procedure room, a dressing room, a sample-collection room, a laboratory, a dispensing counter, a sterile store, an imaging room, an oncology day-care bay or any paediatric clinical area, the HVAC scheme is over.
4. The reason is an engineering reason, not a policy one. Every page I write says clinical rooms stay fragrance-free, and in a standalone scheme that rule enforces itself: the door is shut, the machine is thirty metres away in the lobby, and nothing arrives. Dose a shared supply duct and the rule has no mechanism behind it. A supply grille is permanently open by design — it is the whole point of a supply grille — so there is no equivalent of closing the door. A damper that somebody undertakes to keep shut is a person, not a control, and the first time that damper is opened during a balancing exercise or a filter change, you are dosing a consultation room without knowing it. Fragrance-free is the default in clinical space, and on a duct it stops being a policy you can state and becomes a constraint you have to design around.
5. Where HVAC genuinely wins, it wins properly. A large integrated centre where one AHU serves the entrance, the atrium, the shared waiting hall and the inter-departmental corridors, and the clinical floor is on its own separate system, is the case the Aangan at ₹25,999 was built for: up to 3,000 m³, 800ml, metal body, programmable schedules, under 42 dB, dosed into the supply after the filter so the distribution is the building's own and the level is genuinely even across zones that a single standalone machine could never reach. That is a real and good answer for perhaps one clinic in six.
6. And the hybrid is usually the honest recommendation. Even in a ducted building, the cheapest correct scheme is often one or two standalone units in the public zones and nothing in the ducts at all — because it keeps the clinical separation physical, it does not touch a system your AMC contract covers, and it can be moved on a Tuesday afternoon when the reception desk is relocated. The Vaayu can also be duct-mounted if you want the distribution without the plant-room commitment. Work out the coverage first, because a building with 400 m³ of public volume does not need an AHU tie-in even when one is sitting there available.
A portion of every order supports girl-child education through Nanhi Kali.
2. If you have splits, the answer is standalone and there is nothing further to decide. This is the commonest situation in Indian clinics and polyclinics by a wide margin, and it is not a disadvantage. A standalone Vaayu at ₹11,999 sitting in the reception zone covers up to 1000 m³, which in practice is most of the public volume of a 2,000 to 3,000 sq ft facility. It needs a socket and a shelf. It does not need a contractor, a shutdown, a damper or a conversation with your AMC vendor.
3. If you do have a ducted AHU, trace what it serves before you cost anything. This is the test that matters and it is the one most suppliers skip. Get the drawings, and if there are no drawings, ask the AMC vendor, who will know which AHU feeds which zone because they change the filters. Then write down every room on that AHU. If the list includes a consultation room, an examination room, a treatment or procedure room, a dressing room, a sample-collection room, a laboratory, a dispensing counter, a sterile store, an imaging room, an oncology day-care bay or any paediatric clinical area, the HVAC scheme is over.
4. The reason is an engineering reason, not a policy one. Every page I write says clinical rooms stay fragrance-free, and in a standalone scheme that rule enforces itself: the door is shut, the machine is thirty metres away in the lobby, and nothing arrives. Dose a shared supply duct and the rule has no mechanism behind it. A supply grille is permanently open by design — it is the whole point of a supply grille — so there is no equivalent of closing the door. A damper that somebody undertakes to keep shut is a person, not a control, and the first time that damper is opened during a balancing exercise or a filter change, you are dosing a consultation room without knowing it. Fragrance-free is the default in clinical space, and on a duct it stops being a policy you can state and becomes a constraint you have to design around.
5. Where HVAC genuinely wins, it wins properly. A large integrated centre where one AHU serves the entrance, the atrium, the shared waiting hall and the inter-departmental corridors, and the clinical floor is on its own separate system, is the case the Aangan at ₹25,999 was built for: up to 3,000 m³, 800ml, metal body, programmable schedules, under 42 dB, dosed into the supply after the filter so the distribution is the building's own and the level is genuinely even across zones that a single standalone machine could never reach. That is a real and good answer for perhaps one clinic in six.
6. And the hybrid is usually the honest recommendation. Even in a ducted building, the cheapest correct scheme is often one or two standalone units in the public zones and nothing in the ducts at all — because it keeps the clinical separation physical, it does not touch a system your AMC contract covers, and it can be moved on a Tuesday afternoon when the reception desk is relocated. The Vaayu can also be duct-mounted if you want the distribution without the plant-room commitment. Work out the coverage first, because a building with 400 m³ of public volume does not need an AHU tie-in even when one is sitting there available.
A portion of every order supports girl-child education through Nanhi Kali.
TL;DR: HVAC only where a duct serves the public zones and nothing clinical. Most Indian clinics run splits, have no duct to tie into, and are correctly served by one or two standalone Vaayu units at ₹11,999. Where a duct exists, trace it: a supply serving any clinical room kills the scheme, because a grille cannot be shut like a door. The Aangan at ₹25,999 is for the genuine AHU case — large, integrated, public zones on their own system.
When a tie-in is the right answer, and when it is not
SOSA Aangan ₹25,999
The Aangan connects to an air-handling unit or runs standalone, covers up to 3,000 m³ — roughly 8,000 to 10,000 sq ft — on an 800ml reservoir, in a metal body, programmable, under 42 dB. It is the right machine for a large integrated centre whose public zones sit on their own AHU, and it is the wrong machine for a 2,500 sq ft polyclinic with cassette splits, where recommending it is overselling and I will say so on the phone. Most clinics that ask me this question end up with one Vaayu at ₹11,999 instead, and spend the difference on an extract fan.
The twenty-minute survey, which costs nothing and decides everything
Before anybody quotes you for anything, go and look at your own ceiling. Stand under every grille in the entrance, reception, waiting hall and inter-departmental corridors in turn and classify it as one of three things: a cassette unit, which has its supply louvres and its return grille in the same square panel and serves only the room it is in; a terminal on a duct, which is a slot or a louvred grille with no return beside it and air arriving from somewhere else; or a hi-wall split, which is obvious. Then find the nearest ceiling access panel and look in. A 150mm flexible duct running two metres to the next grille is a ductable split. A 400mm insulated rigid duct heading for a riser is a central system. That distinction is the whole of this article, it takes twenty minutes, and it is free. Ask your fit-out contractor for the air-conditioning layout drawing; ask your AMC vendor which unit serves which zone, because the person who changes the filters knows the system better than the drawings do. And while you are up there, look at the drain pan and the condensate line, because the free list starts there and a musty supply will defeat any scheme you build on top of it.
1
CASE ONE
Splits throughout, no common duct, and therefore no HVAC option
This is where most Indian clinics and polyclinics actually are, and I want to be clear that it is not a deficiency. Sixteen cassette and hi-wall units recirculating room air are a perfectly ordinary way to cool a 3,000 sq ft clinic, and the absence of ducting removes an entire category of problem: there is no shared path for anything to travel along, which means your clinical rooms are separated from your public areas by walls and closed doors rather than by a promise about a damper. What you buy is standalone, and the specification that matters is not coverage but operating burden. The Vaayu at ₹11,999 is waterless cold-air nebulisation with no standing water reservoir, which in a building running twelve hours a day is the difference between a machine somebody owns and a machine nobody empties. It is 0.9 kg and 165 × 80.5 × 215 mm, so it sits on a shelf behind the reception desk or wall-mounts at about two metres; it holds 400ml for roughly seventy-five days, so four refill visits a year by one named person; it takes an app and 1h/4h/8h/24h timers, so the facility team sets the opening hours from the office and the centre head never touches it; it runs under 38 dB; and it key-locks, which is the only reason a machine can stand in a public waiting hall at all. One unit covers up to 1000 m³. Do the sum before you buy a second one, because one machine is usually the answer once the clinical rooms come out of it. What you do not buy is a water tank: the ultrasonic Sukoon at ₹1,899, Boond at ₹899 and Megh at ₹3,499 hold standing water and add 30 to 50 ml of water an hour to the air, which is honest for a single administrative cabin with a named person emptying and drying it daily and wrong for public clinical property.
2
CASE TWO
A ducted AHU — and the one question that ends most of these schemes
If you have a genuine central system, the attraction is real: the building's own distribution gives you an even level across zones that no single standalone unit could reach, and the machine lives in a plant room where nobody can see it or adjust it. The question that has to be answered first is not whether the AHU has capacity. It is which rooms are on it. Write the list out. In a surprising number of fit-outs, one AHU was specified for a whole floor because it was cheaper than two, and the consultation cabins hang off the same trunk as the waiting hall. If any clinical room shares that supply, the scheme stops there, and it stops for a reason you cannot engineer your way around with goodwill: a supply grille has no shut position. In a standalone scheme, “clinical rooms stay fragrance-free” is enforced by a door that a nurse closes. On a shared duct it is enforced by nothing. A balancing damper is a metal flap somebody set once; the next time a technician opens it to chase an airflow complaint, a consultation room is being dosed and nobody is told. I have talked clinics out of HVAC schemes on exactly this point, and keeping fragrance out of clinical zones while scenting the public areas goes through the whole separation question properly. Where the answer comes back clean — public zones on their own AHU, clinical floor on its own system or on splits — then the Aangan at ₹25,999 is the right machine: HVAC-connected or standalone, up to 3,000 m³, 800ml, metal body, programmable schedules, under 42 dB. Dose downstream of the filter, on the supply side, with the AMC vendor present, and get the zone list written into the handover sheet rather than agreed verbally.
3
CASE THREE
The ductable split, which looks central from below and is not
The third case is the one that produces the most wasted quotations. A ductable or slim-duct split has its indoor unit sitting above the false ceiling with a short run of duct to two or three grilles in the room or the corridor below it. From underneath it looks like a central system. It is not one: it recirculates the air of the zone it serves, it has no outside-air connection, its filter is a plastic mesh in the unit rather than a filter bank, and its total airflow is sized for one zone. Dosing into that duct is not an HVAC scheme — it is a standalone machine in an awkward location, with the cost of an access hatch and the inconvenience of a machine you cannot reach to refill without a ladder and a ceiling panel. If the zone it serves is entirely public, you may as well put the Vaayu on a shelf in that zone and keep the refill at waist height. If the zone it serves includes anything clinical, the same rule as case two applies and the answer is no. The honest summary of all three cases is that an HVAC tie-in is right for perhaps one clinic in six, it is right for reasons of building shape rather than quality, and the other five are properly and completely served by standalone units costing less than half as much. The Vaayu-versus-Aangan comparison sets the same question as a buying decision across five facility shapes.
The instruction I would give a facility manager: do the survey before you take a single call from a supplier. If a vendor offers an HVAC scheme without having asked which rooms are on the AHU, they have not surveyed your building, and you are being sold a product rather than advised on one.
Every system shape, and what is actually available to it
Find your building in the left-hand column. The recommendation in the right-hand column assumes the public volume sum has already been done and the clinical rooms have already come out of it, because that changes the machine more often than the ducting does.
Print this
What your air-conditioning system allows, and what it rules out
| The system you have | How to recognise it | Is a tie-in available? | What to buy |
|---|---|---|---|
| Cassette and hi-wall splits ★ | Supply louvres and return grille in the same ceiling panel, or a wall unit. One unit per room, no common duct anywhere | No. There is nothing to tie into, and that is not a problem | Vaayu ₹11,999, freestanding or wall-mounted in the public zones |
| Ductable or slim-duct splits | Indoor unit above the ceiling, 150mm flexible duct, two or three grilles, no return bank, no outside-air connection | Technically yes, practically pointless — it is one zone, recirculating | Vaayu ₹11,999 standing in that zone, at refill height |
| A ducted AHU serving public zones only | Plant room, filter bank, rigid insulated supply ducting to a riser, return path back to the AHU, zone list confirmed by the AMC vendor | Yes, and this is the case the Aangan exists for | Aangan ₹25,999, dosed downstream of the filter |
| A ducted AHU shared with any clinical room | The zone list includes a consultation cabin, a laboratory, a collection room, dispensing, imaging or a day-care bay | No. A supply grille cannot be shut like a door | Standalone only. Separate the zones physically |
| Public zones ducted, clinical floor on splits | Two systems with two different vintages, which is common where a clinic has expanded into an adjoining unit | Yes for the public AHU, and the separation is already physical | Aangan ₹25,999 if public volume exceeds 1000 m³, otherwise Vaayu |
| A double-height atrium on a central system | One tall volume, galleries looking into it, supply high on the walls or in the soffit | Yes, and here it is genuinely better than a floor-standing unit | Size the atrium by volume, then Aangan |
| No air conditioning in the public areas | Ceiling fans, open frontage, a lobby that is ventilated rather than cooled | No, and air change is doing work a machine cannot | Vaayu ₹11,999 on low, or reed diffuser from ₹749 in a small lobby |
| Never | A tie-in agreed on the basis that a damper will be kept closed, or a scheme quoted by a supplier who never asked which rooms are on the AHU | Never. A person is not a control | — |
Shop this guide
The standalone answer, the tie-in answer, and the refill
Vaayu · standalone or duct-mounted₹11,999Shop → Aangan · HVAC or standalone₹25,999Shop → Vaayu · wall mount₹11,999Shop →
The SOSA principle
An HVAC tie-in is a building answer, not a quality answer. It is right where a duct serves the public zones and nothing clinical. In every other building, standalone is not the compromise — it is the correct answer, and it costs less than half as much.
A door can be closed. A supply grille cannot. That single sentence decides more of these schemes than coverage, capacity or price.
The duct that serves a clinical room, and what to do instead
I want to spend a paragraph on the failure mode, because it is the only part of this subject that can actually do harm. A clinic ties scenting into a single AHU that serves a whole floor. The intention is the lobby and the corridor. The reality is that the same trunk feeds four consultation cabins, a dressing room and the sample-collection room, because that is how the fit-out was cheapest in 2019. For six months nobody notices, because the level is low and the cabins have their own cassette units running most of the time. Then the season changes, the cassettes run less, the AHU runs more, and a physician tells you that she can smell your lobby in her consulting room. At that point you have a clinical conversation you cannot win, because a doctor is trained to notice what a room and a patient smell of, and you have put something in her air that she did not agree to and cannot remove by closing her door. The fix is not a lower setting. The fix is removing the machine from the duct, which means the money and the access work were wasted. This is why the zone list has to be written down before anything is ordered, and why I would rather lose an Aangan sale than make it on an untraced duct. The areas that always stay fragrance-free is the list to hold the drawings against, and which departments get it and which do not is the version to take into a meeting with your medical director.
What to do instead is undramatic and it works. Put a standalone machine in each public volume and let walls and closed doors do the separation, which is the only separation mechanism in a clinic that does not depend on anybody remembering anything. A 3,000 sq ft polyclinic with 3m ceilings has a plan volume of about 836 m³, and once the consultation cabins, the procedure room, the laboratory and the collection room come out, the public volume is commonly 350 to 450 m³ — comfortably inside one Vaayu, with the machine standing in the reception zone where the refill is at waist height and the key-lock is doing its job in full view. A 6,000 sq ft centre over two floors is usually two units, one per floor lobby, running the same scent on the same timer, which is the two-floor case in detail. Where the public volume genuinely exceeds 1000 m³ — an atrium, a large integrated centre, a mall-format polyclinic with a long concourse — the Aangan earns its ₹25,999 whether it is ducted or standing in the corner, because it is the only machine in the range that covers up to 3,000 m³. And if you want duct distribution without a plant-room commitment, the Vaayu itself is rated for freestanding, wall or HVAC mounting, so a single public-only ductable zone can be dosed with the ₹11,999 machine rather than the ₹25,999 one.
The costs, plainly, because this is the paragraph a purchase order gets written from. The Vaayu is ₹11,999 and needs a socket and a shelf: no contractor, no shutdown, no access hatch, no AMC vendor, and it can be relocated by one person in five minutes when the reception desk moves. A 400ml fill lasts about seventy-five days on clinic opening hours, so four refills a year per machine, which procurement can model in ten minutes; it ships with four hotel-inspired scents, so the first month of trialling costs nothing; and the bottle I would hold a medical facility to is the lightest available — a white-tea character in the lobby, or a clean green one where a café corner reaches the seating — with the test being that a patient should not be able to tell you what the fragrance is, only that the place did not smell of anything unpleasant. The Aangan is ₹25,999 for the machine, and a tie-in adds installation: an access position on the supply duct, the AMC vendor present for an hour, a schedule programmed to the opening hours, and the zone list signed off. Budget that as a small facilities job rather than a product purchase, put it in the facilities line and not in marketing, and name the person who refills the 800ml reservoir before you raise the order — the procurement checklist has the questions in the order a purchase committee asks them. Candles are not appropriate in a healthcare building at any price, because an open flame is a fire-safety and insurance matter, and SOSA does not make a room spray.
A tie-in is the right answer for about one clinic in six, and the deciding factor is the duct, not the budget. If the supply to your public areas cannot be separated from the supply to your consulting rooms, buy the standalone machine and sleep properly.
— Sonal Sahani, SOSA
The SOSA edit
The same decision as five tiers, in the order a facilities meeting works through them, with the one thing nobody should agree to at the bottom.
The SOSA edit
Survey, trace, size, then choose the machine
| Tier | What is in it | When it earns its place | Cost |
|---|---|---|---|
| 1. The survey ★ | Classify every public-area grille. Get the AC layout drawing. Ask the AMC vendor which unit serves which zone, and write one sentence down | Before any supplier is called. Twenty minutes, and it decides the whole scheme | ₹0 |
| 2. The zone list | Every room on the AHU that serves your public areas, written out and checked against the fragrance-free list | Immediately after the survey. One clinical room on the list ends the HVAC option | ₹0 |
| 3. The volume sum | Area in sq ft divided by 10.76, times ceiling height in metres, counting only the volumes a door closes | Before choosing between the machines. The arithmetic, taught in full | ₹0 |
| 4. Vaayu — standalone | Waterless, no standing water tank, up to 1000 m³, 400ml ≈ 75 days, app and 1h/4h/8h/24h timers, under 38 dB, 0.9 kg, freestanding, wall or duct mount, auto-stop, key-lock | Splits throughout, or a ducted building where separation must stay physical. Most clinics | ₹11,999 |
| 5. Aangan — the tie-in | HVAC-connected or standalone, up to 3,000 m³, 800ml, metal body, programmable, under 42 dB | A public-only AHU and more than 1000 m³ of public volume. Roughly one clinic in six | ₹25,999 |
| Not on the list at any price | A tie-in to a duct that also serves a clinical room, a scheme held together by a damper somebody promises to keep shut, or an Aangan sold into a 2,500 sq ft polyclinic | Never. A supply grille has no shut position, and one machine per floor is usually wrong too | — |
Honest notes for buyers: on this page specifically, an HVAC tie-in is an engineering decision about which rooms share a supply duct, and where a clinical room is on that duct the answer is standalone units, because a supply grille cannot be closed the way a consulting-room door can. In general, fragrance in a medical facility is housekeeping and presentation, never treatment. Nothing here claims that a fragrance reduces anxiety, aids recovery, improves sleep, cleans or disinfects air, or has any clinical effect whatsoever, because it does not and a diffuser is not an air purifier. Scenting belongs to the entrance, reception, shared waiting areas, inter-departmental corridors and administrative rooms. Consultation and examination rooms, treatment and procedure rooms, day-care surgery, dressing rooms, blood- and sample-collection rooms, laboratories, pharmacy dispensing, sterile stores, imaging rooms, oncology day-care and paediatric clinical areas should be left fragrance-free. A persistent smell is information about a dry drain trap, a bin, a soiled-linen route or an air-conditioning drain pan: find it and fix it rather than covering it. On the machines: the Vaayu at ₹11,999 is waterless cold-air nebulisation with no standing water tank, covering up to 1000m³ or roughly 2,000–3,000 sq ft, with a 400ml tank lasting about 75 days, app control, 1h/4h/8h/24h timers, under-38dB running, auto-stop and a key-lock for public areas. The Aangan at ₹25,999 covers up to 3,000m³ and connects to HVAC for a whole floor or an atrium. The ultrasonic Sukoon, Boond and Megh are water-based, hold standing water and add 30–50 ml of water an hour to the air, which suits a single administrative cabin with a named person emptying and drying the tank daily and is unsuitable for public clinical property. An alcohol-free reed diffuser needs 24–72 hours to establish and suits a small lobby rather than a large waiting hall. Candles are not appropriate in a healthcare facility because an open flame is a fire-safety matter. SOSA does not make a room spray. The Hotel Collection scents are SOSA's own interpretations inspired by the world's finest hotels; SOSA is an independent Indian fragrance house, not affiliated with or endorsed by any hotel brand. A portion of every order supports girl-child education through Nanhi Kali.
The answer for five clinics out of six
SOSA Vaayu ₹11,999
Waterless cold-air nebulisation with no standing water tank, up to 1000 m³ or roughly 2,000 to 3,000 sq ft, a 400ml fill lasting about seventy-five days, Bluetooth app plus 1h/4h/8h/24h timers, under 38 dB, auto-stop and a key-lock, 0.9 kg at 165 × 80.5 × 215 mm, freestanding or wall-mounted or duct-mounted. It needs a socket and a shelf. No contractor, no shutdown, no access hatch, and no dependence on a damper staying shut — which is why it is the right machine in a building where the clinical rooms and the public areas share any part of their air. Public areas only, on low, for the opening hours.
SS
ISIPCA
Versailles
Versailles
A note from Sonal
The first HVAC tie-in I was ever asked to quote was for an integrated centre in Pune, and I nearly sold it. The centre head had an AHU, a plant room, a maintenance vendor on contract and a budget line already approved, and he wanted the whole public floor dosed from the supply. What stopped it was a question I asked almost as filler while we were waiting for the drawings — which rooms are on this unit — and the answer, forty minutes later, was the lobby, the corridor, the registration desk, two consultation cabins and the sample-collection room. He had not known. The vendor who maintained the system had not been asked. Nobody had done anything wrong; the fit-out had simply put one AHU where two would have been better, six years earlier, for perfectly ordinary reasons of cost.
We put two standalone machines in the public zones instead, at less than half the price, and I have asked that question first in every conversation since. What I have learned from asking it is that the split-unit clinic, which I used to think of as the constrained case, is actually the easy one: there is no shared path, so the rule that clinical rooms stay fragrance-free is enforced by a door rather than by somebody's memory of an agreement about a damper. The ducted building is the one that needs care, and the care is all in the hour before the order, not in the machine. I would rather spend that hour and sell the ₹11,999 unit than skip it and sell the ₹25,999 one, because the second kind of sale comes back, and when it comes back it comes back as a physician in a doorway telling me she can smell my lobby in her consulting room.
Everything is made and supported from Pune, and a part of every order funds girl-child education through Nanhi Kali. You get a space that smells like somewhere looked after; a girl gets a classroom. That equation has always felt right to me.
Frequently asked questions
Should a medical centre connect scenting to its HVAC or use standalone units?
Connect to HVAC only where a ducted central system serves the public zones and nothing clinical. Most Indian clinics run cassette and hi-wall splits with no common duct, so there is nothing to tie into and standalone is the correct answer rather than a compromise. Where a duct does exist, list every room on it first: if any consultation room, laboratory, dispensing counter, collection room, imaging room or day-care bay shares that supply, use standalone units instead.
Why does a duct that also serves a consultation room rule out an HVAC scheme?
Because a supply grille has no shut position. In a standalone scheme the rule that clinical rooms stay fragrance-free is enforced physically, by a closed door and thirty metres of corridor. On a shared supply duct it is enforced by a balancing damper that somebody has undertaken to keep closed, and the first time a technician opens it during a filter change or an airflow complaint, a clinical room is being dosed and nobody is informed. A person is not a control.
How do I tell whether I actually have a ducted system?
Stand under each public-area grille. A cassette has its supply louvres and its return grille in the same ceiling panel and serves only that room. A slot or louvred grille with no return beside it is fed from a duct. Then open the nearest ceiling access panel: a 150mm flexible duct running two metres to the next grille is a ductable split serving one zone, while a 400mm insulated rigid duct heading for a riser is a central system. The air-conditioning layout drawing and your AMC vendor will confirm it in ten minutes.
Can the Vaayu be mounted in a duct, or is it only freestanding?
It is rated for freestanding, wall-mounted and HVAC-mounted use, so a single public-only ductable zone can be dosed with the ₹11,999 machine instead of the ₹25,999 one. In practice I usually recommend standing it in the zone rather than putting it above a ceiling, because the 400ml refill every seventy-five days is then at waist height rather than up a ladder behind an access panel, and the key-lock is doing its job where you can see it.
When is the Aangan genuinely the right machine?
When the public volume exceeds 1000 m³ and the public zones have their own air-handling unit — a large integrated centre, a double-height atrium with galleries, a long mall-format concourse. It covers up to 3,000 m³ on an 800ml reservoir, in a metal body, programmable, under 42 dB, HVAC-connected or standalone, at ₹25,999. In a 2,500 sq ft polyclinic it is overselling, and a single Vaayu at ₹11,999 is the honest recommendation.
Survey first, then choose
Trace the duct before you cost the machine — and five clinics in six will end up standalone
The Vaayu is ₹11,999: waterless cold-air nebulisation with no standing water tank, up to 1000 m³ or roughly 2,000–3,000 sq ft, a 400ml tank lasting about seventy-five days for four refills a year, Bluetooth app control with 1h/4h/8h/24h timers, under 38 dB, auto-stop and a key-lock, 0.9 kg at 165 × 80.5 × 215 mm, freestanding or wall or HVAC mounted, supplied with four hotel-inspired fragrances. The Aangan is ₹25,999 for up to 3,000 m³, HVAC-connected or standalone, 800ml, metal body, programmable, under 42 dB. Free shipping above ₹499, and a portion of every order supports girl-child education through Nanhi Kali.
See the Vaayu · ₹11,999 See the Aangan · ₹25,999
Continue the read
More from SOSA
- Vaayu or Aangan: Which Diffuser Suits a Multi-Speciality Clinic? — the same decision as a buying guide, across five facility shapes.
- How Do I Scent a Multi-Floor Medical Centre Where Each Floor Is a Different Speciality? — what a tie-in does and does not solve when the specialities are stacked.
- How Do I Work Out the Coverage a Clinic Needs Before Buying a Diffuser? — the volume sum, which changes the machine more often than the ducting does.
- How Do I Keep Fragrance Out of Clinical Zones While Scenting the Public Areas? — the separation question, in the detail a medical director will ask for.
- Brand: the SOSA founder story.
Editorial standards & sources
Product facts used in this guide. SOSA Vaayu Rs 11,999: waterless cold-air nebulising diffuser, no water reservoir, coverage up to 1000m3 (approximately 2,000-3,000 sq ft), 400ml refillable tank lasting up to about 75 days per fill, Bluetooth app plus onboard control, 1h/4h/8h/24h timer scheduling, adjustable intensity, under 38 dB, DC 12V/1A at 5W, 165 x 80.5 x 215 mm and 0.9 kg, freestanding or wall or HVAC mounted, auto-stop and key-lock, CE, RoHS and SGS certified, supplied with four hotel-inspired fragrances. SOSA Aangan Rs 25,999: HVAC-connected or standalone commercial nebulising diffuser, coverage up to 3,000m3 (roughly 8,000-10,000 sq ft), 800ml reservoir, metal body, programmable schedules, under 42 dB. Ultrasonic machines are water-based, hold standing water and consume 30-50 ml of water an hour: Sukoon Rs 1,899 (500ml, 270-320 sq ft, 16-18 hours on low, three 15ml Hotel Collection scents included), Boond Rs 899 (300ml), Megh Rs 3,499 (6 litres). Hotel Collection water-based fragrance 15ml Rs 299, 100ml Rs 999, 300ml Rs 1,799. Alcohol-free reed diffusers from Rs 749, requiring 24-72 hours to reach their working level. Free shipping above Rs 499. Coverage arithmetic: cubic metres equal floor area in square feet divided by 10.76 and multiplied by ceiling height in metres, counting only the volumes that are actually scented. This guide makes no medical, therapeutic or clinical claim of any kind for fragrance: a diffuser does not purify, disinfect or clean air, and does not treat, calm or affect any patient or condition. Fragrance is housekeeping and presentation. Clinical areas should be left fragrance-free, and a persistent odour should be traced to its source and corrected rather than covered. SOSA is not affiliated with or endorsed by any hotel brand. Prices subject to change - see the live product pages.