The question usually arrives in good faith and with a reasonable premise: reception is a short stop, the lounge is a four-hour wait, the private room is smaller, so surely each should sit at its own level. The premise is right. The obstacle is physical. You cannot hold two different levels inside one connected body of air. If your entrance, reception counter and attendant lounge form one open-plan space with no doors between them, that is one room as far as air is concerned, whatever the furniture layout implies, and it will settle at one level no matter how many machines you put in it. A 1,500 sq ft open front of house at a 12 ft ceiling is 18,000 cubic feet, about 510 cubic metres, and every part of it shares the same air.
So the first half of this page is a correction: count your volumes before you count your rooms, and where there is one volume there is one level - set by the longest dwell in it, which is the lounge, not the counter.
The second half is the design that applies where there genuinely are doors. One register throughout, because a change of character at a doorway is far more noticeable than either register on its own. Different levels per volume, chosen by dwell, enclosure and who is in the room. And some volumes at zero - the private lounge off the clinical corridor, the patient holding area, and the whole clinical half, which gets nothing at all.
And then the part nobody plans for and everybody experiences: drift. Several separately adjustable units in one building end up at several different settings within a year unless one named person owns them. A level plan that lives in somebody's head is not a plan. It is a starting condition.
How do I set the level in an open-plan hospital front of house? By the longest dwell, not the average. If entrance, reception and lounge share one volume - a 1,500 sq ft public area at 12 ft is 18,000 cubic feet, about 510 cubic metres - the person who sets the level is the attendant sitting there for four hours, not the visitor passing the counter for four minutes. That produces a level that feels faint at the doorway, and it should. The doorway person was never going to be the one who minds.
Why do our units end up at different settings? Because every adjustable dial in a building gets adjusted. A well-meaning supervisor turns one up on a quiet afternoon when their nose has adapted, somebody else turns another down after a comment, a unit is refilled and comes back on a different setting, and nobody records any of it. Three units nudged twice a year by two different people is six undocumented changes. The fix is a card on each machine, a written plan, and one named person who owns the settings.
So begin with a count that takes five minutes and settles the argument. Walk the public half and mark not rooms but volumes. A volume ends where a door ends it, and only where that door is shut as a normal state. An archway is not a boundary. A glazed screen with a permanent opening in it is not a boundary. A low partition, a planter run, a change in floor finish and a different ceiling treatment are not boundaries - they are furniture. A pair of doors that are propped open every morning for trolleys and pushchairs is not a boundary either, whatever it is on the drawing.
When you have done that, most facilities find they have two volumes in the public half and not five. Typically: one large connected front of house containing the entrance, the counter and the open lounge, and one or two enclosed rooms off it. That changes the question entirely. Inside the big volume, you do not get to choose different intensities. You will get one level, because air moves, and the only thing several machines in one volume achieve is a stronger version of the same single level with hot spots near each unit.
Do the arithmetic on that volume so the scale is real. A 1,500 sq ft open public area at a 12 ft ceiling is 1,500 x 12 = 18,000 cubic feet, and 18,000 / 35.3 is about 510 cubic metres. Break it down the way the furniture does and the parts add up to the same thing: a 500 sq ft entrance zone at 12 ft is 6,000 cubic feet or about 170 cubic metres, a 400 sq ft reception and billing area at 12 ft is 4,800 cubic feet or about 136 cubic metres, and a 600 sq ft lounge at 12 ft is 7,200 cubic feet or about 204 cubic metres. 6,000 plus 4,800 plus 7,200 is 18,000 cubic feet, and 170 plus 136 plus 204 is 510 cubic metres. Three zones on the plan, one body of air.
Now the rule that follows, and it is the most useful sentence on this page: in one volume, the longest dwell sets the level. Not the average, not the entrance, not the point of sale. If the lounge inside that volume holds a family for four hours, then the whole volume runs at the level that is still unobtrusive at hour four - which means the entrance will feel faint to somebody walking in, and that is correct. The person at the doorway was never going to be the one who minds. The person at hour four was.
Where there genuinely are doors, you have a real choice and the design is straightforward: one register, different levels, some rooms at zero. One register because a family crosses between these spaces several times in a morning and a change of character at a doorway is conspicuous in a way neither register is on its own. Different levels because a small enclosed room with a long wait needs less than an open area with high air exchange. And zero for the rooms where the honest answer is nothing - the private lounge that opens onto the clinical corridor, the patient holding area next to the procedure doors, and the whole clinical half, which gets nothing at any level.
Then write it down, because this is the part that fails. A portion of every SOSA order supports girl-child education through Nanhi Kali.
The commonest mistake this question leads to is buying more machines than the building needs. A facility decides it wants three intensities, buys three units, puts them in one open front of house, and discovers within a month that the lobby is now noticeably stronger everywhere and that the three dials do not produce three zones. They produce one zone with three sources in it. If you have one volume, you need one machine sized for that volume - and a SOSA Vaayu at ₹11,999, rated for approximately 1000 cubic metres of connected air, is generously sized for the 510 cubic metre example above.
The second mistake is mistaking a visual boundary for an air boundary. Interior design is very good at making one room feel like three: a change of ceiling, a planter run, a rug, a step, a screen. All of that is real to a person and invisible to air. If you can walk from the counter to the lounge without opening anything, they are one volume.
The third is setting for the wrong person. Every instinct pushes you to set the level for the entrance, because that is where you stand when you judge it and because arrival feels like the important moment. In a building where the same volume also contains a four-hour wait, setting for the entrance means the lounge runs at whatever the entrance needed, and the entrance needs more because it has an automatic door exchanging air with the street all morning. That is the mechanism by which lounges end up too strong: nobody dosed the lounge, they dosed the door.
And the fourth is treating the plan as a conversation rather than a document. Levels that are agreed verbally last about a quarter. Write the register and the number for every unit on a card taped to the machine, keep one sheet with every unit listed and its setting, and name one person - a facility manager, a front-office head, whoever actually walks the building - who owns changes. Without an owner, three adjustable units become three unrelated decisions within a year, and the building stops having a character at all.
Two constants regardless of how many volumes you have. Never reduce ventilation, close vents or slow air handling so a zone holds its fragrance longer - a well-ventilated public area is genuinely harder to scent and that is a fact this page accepts. And the clinical half runs nothing at any level, with your clinical, infection-control and engineering leadership owning that list and able to extend it.
One volume or several - and why the answer is usually fewer than you think
There are three things to work out, in order, and the first one usually shortens the other two considerably.
The first is how many volumes you actually have, which is a physical question with a physical answer and has nothing to do with how many waiting areas your signage names. The second is what sets the level inside each volume, which is dwell first, enclosure second and air exchange third. The third is who owns the settings, which sounds like an administrative footnote and is in fact the reason most multi-zone scenting plans fail within a year.
Before any of it, the mechanism, because everything here rests on it. A coverage rating assumes one connected body of air. A machine cannot push scent through a closed door, and it cannot maintain a gradient inside an open space either - air mixes, and a room settles. Those two facts together are the whole physics of this page. The first is what makes a fragrance-free clinical half deliverable. The second is what makes "different intensities in an open-plan lobby" undeliverable. They are the same fact seen from two sides, and it is worth holding both at once, because a supplier who tells you they can give you three intensities in one open room is contradicting the same physics they will later rely on to promise you a neutral clinical zone.
It is also worth naming what a genuine boundary looks like in a day-care hospital, since the answer is specific. A solid door that is shut as a normal working state is a boundary. A door with a closer on it that people actually let close is a boundary. A lobby separated from a lift core by a second set of doors is two volumes. What is not a boundary: an archway, a glazed screen with an opening, a change of floor or ceiling, a planter run, a reception desk however large, a staircase, a corridor that stands open at both ends, and any door that is propped for trolleys, deliveries or pushchairs during working hours. And a door that is shut but whose room shares a return path with the next room through the ceiling void is a partial boundary at best - that is an engineering question for your own facilities team, not one a page can settle.
Finally, a word about the honest commercial consequence, because it points the same way as the rest of this bank. Counting volumes properly usually reduces the purchase. A facility that expected four machines finds it needs one for the connected front of house and possibly one small unit for an enclosed room, with a couple of rooms at zero. That is the correct answer arriving early rather than a smaller sale being talked into you.
Take a typical open front of house in a private day-care hospital: an entrance zone, a reception and billing counter, and an open attendant lounge, all in one space with no doors between them. Say 1,500 sq ft in total at a 12 ft ceiling. That is 1,500 x 12 = 18,000 cubic feet, and 18,000 / 35.3 is about 510 cubic metres. Break it the way the furniture breaks it: entrance 500 sq ft at 12 ft is 6,000 cubic feet, about 170 cubic metres; reception and billing 400 sq ft at 12 ft is 4,800 cubic feet, about 136 cubic metres; lounge 600 sq ft at 12 ft is 7,200 cubic feet, about 204 cubic metres. The parts sum exactly to the whole - 6,000 plus 4,800 plus 7,200 is 18,000 cubic feet, and 170 plus 136 plus 204 is 510 cubic metres - which is a useful reminder that the division exists on the drawing and not in the air.
Now imagine trying to run three intensities in it. Put a unit in each zone at three different settings. What happens is not three zones; it is one volume receiving the combined output of three machines, with a local concentration around each one. The overall level goes up, the lounge - which needed the least - now receives the sum, and the only differentiation you have achieved is that standing next to a machine smells stronger than standing away from it, which is true of one machine as well. Meanwhile you have bought three machines and three sets of refills to achieve a worse version of what one correctly sized machine would have done.
So in one volume, one level. Which raises the only real question: whose level? The longest dwell in the volume sets it. If that 510 cubic metre space contains a lounge where families sit for four hours, the level for the entire space is the level that is still unobtrusive at hour four. The four-minute visitor at the counter and the ten-second walk-through at the door are both comfortably served by a level set for hour four; the reverse is not true, and a level set for the entrance is roughly double what the lounge can carry.
There is a second reason the entrance must not set the level, and it is mechanical. An entrance has automatic doors that open for every arrival, every discharge, every attendant stepping out and every delivery, which is a continuous partial exchange of that air with the street. That means the entrance always reads weaker than the rest of the volume, and the instinct is to compensate. Compensating for a genuine air change by raising the output of the whole volume is how lounges become too strong, and it is the single commonest failure in a large open front of house. The correct response is to accept that the threshold will read faint during the morning rush, because during the morning rush the threshold mostly smells of the morning rush, and it is going to do that regardless.
What you can legitimately do inside one volume is placement, which is not the same as intensity but is the nearest thing available. Put the unit in the part of the volume that is furthest from the doors, aimed into the body of the space, away from any supply throw and away from any return grille - and never in a corridor, and never near a door that leads to the clinical side. That gives the space a source rather than a plume, and it lets the level be lower overall.
And the honest limit: if you genuinely need two different intensities in what is currently one open space, the answer is not a second machine. It is a door, which is an architectural decision, or it is accepting one level. There is no third option, and any supplier offering one is selling you something the air will not deliver.
One register throughout. This is not negotiable if you want the building to read as one place. A family moves between the entrance, the counter, the lounge, the corridor and sometimes a private room several times in a morning, and a change of character at a doorway is conspicuous in a way that neither register would be on its own. Two registers in one building reads as two suppliers, or as a room that was decorated separately - exactly the impression a premium facility is trying not to give. Consistency is the free part of commercial scenting: one register held across every scented volume is what turns a purchase into a house character, and it costs nothing.
Different levels per volume, chosen in this order: dwell, enclosure, air exchange. Dwell first, because a longer wait means continuous exposure rather than sampled exposure. Enclosure second, because a shut door means less dilution and because smaller rooms are a smaller number of cubic metres than people assume - a 180 sq ft private lounge at 10 ft is 1,800 cubic feet, about 51 cubic metres, which is a quarter of a 600 sq ft lounge at 12 ft. Air exchange third, because an entrance with automatic doors loses fragrance faster than anywhere else in the building and yet must not be allowed to set the level for rooms that do not.
In practice that produces a pattern that looks upside down and is correct: the big open front of house at a low level, the enclosed lounge lower, the small private room lower still or off. The smaller, quieter, more expensive room gets less, not more. Its occupant is also, frequently, the person least able to tell you it is too much, which is a separate argument pointing the same way.
Some volumes at zero, named explicitly. This is the part that must be written as a list of rooms rather than as a principle, because a principle gets reinterpreted and a list does not. The whole clinical half sits at zero: pre-operative areas, procedure and operating rooms, post-procedure and post-anaesthesia recovery, sterile and decontamination areas, clinical and drug storage and clinical waste. Nothing at all, not a lower setting, not a subtler register. Nausea after anaesthesia is ordinary and widely known and is a plain reason those areas stay neutral; this page makes no claim in either direction about what a fragrance does about it. Alongside them, several public rooms often belong at zero too: a patient holding area beside the procedure doors, where somebody waiting to be called is not in a state to be marketed at; a private lounge that opens onto the clinical corridor; and any room where your engineers have found a shared return or a corridor carrying transfer air.
Then the document itself, which should be short enough that anybody can read it. One sheet, one line per volume: the room name, the register, the level, and whether it is on a timer. A second short list headed "fragrance-free zones" naming every room at zero. A note that says the fragrance-free list is owned by the clinical and infection-control leads and can only be extended, never reduced, by them. That single page does more for consistency than any machine you buy, it survives staff turnover, and it is the thing you hand to a new facility manager on their first day.
And the governance sentence that belongs on the sheet itself: what may be introduced into the air of a building with a surgical zone is decided by the facility's own clinical leadership, infection-control policy and facilities engineering, and their decision overrides the plan - including when the answer is that a room comes off the scented list entirely.
Every adjustable dial in a building gets adjusted. Not maliciously and usually not even noticeably. A supervisor walks through the lounge on a slow Thursday afternoon, has been in the building since eight, cannot smell anything - because their nose adapted hours ago, which is ordinary and universal - and nudges it up. A family mentions it at the desk on a Monday and somebody turns that unit down two notches to be helpful. A machine is taken away to be cleaned and comes back on whatever setting it was last on rather than the one it should be. Somebody new starts, finds an unfamiliar device, and sets it to the middle because the middle seems sensible.
Count the arithmetic of that. Three separately adjustable units, each touched twice a year by two different people acting reasonably, is six undocumented changes in a year, none of them recorded and none of them wrong from the point of view of the person making it. After twelve months you have three units at three settings nobody chose, and the building no longer has a level - it has a history. After twenty-four months, nobody in the facility can tell you what any of them is supposed to be.
The symptoms are recognisable. The lounge is stronger than the entrance despite the plan saying the opposite. One area has been "too much" for months and somebody has been meaning to look at it. A new manager asks what the settings should be and gets three different answers. Or the classic: a director says the fragrance "does not work like it used to" and wants to change register, when what has actually happened is that three machines have drifted away from each other and the building no longer reads as one place.
The fix is administrative and it is cheap.
A card on every machine. Register and number, written on the housing where the person adjusting it will see it. That alone stops perhaps half of the drift, because most nudges are made by people who had no idea there was a correct value.
One sheet listing every unit. Room, register, level, timer hours. Kept where the facility manager keeps everything else, not in somebody's email.
One named owner. A person, not a role in the abstract - the facility manager, the front-office head, whoever actually walks the building daily. Changes go through them and get written on the sheet. Anybody may switch a unit off without asking - that is a standing arrangement and it stays unrestricted - but nobody changes a level without telling the owner.
A monthly walk. Ten minutes, first thing, before the building has been open long enough for anyone's nose to adapt. Walk from the street in, through each volume, and check each unit against the card. Ask the housekeeping team and the desk team what they have noticed; they are in that air eight to ten hours a day and are the most exposed people in the building, and a report from them carries more weight than your own impression, not less.
One final point that belongs here because it is the cheapest way to avoid drift altogether: fewer adjustable devices. A building with one correctly sized machine for the connected front of house and a reed diffuser from ₹749 in an enclosed room has one dial in it. A reed has no setting to change, no timer to reset and nothing for a well-meaning supervisor to nudge, and in a small room that constraint is worth more than flexibility. Where a machine is right, the Bluetooth app and timer on a SOSA Vaayu at ₹11,999 help for the same reason: the schedule is set once, it runs the OPD hours and stops, and the setting lives somewhere other than in the memory of whoever walked past last.
- Walk the public half and mark volumes, not rooms - a door that stays shut ends one.
- Inside each volume, set the level by the longest wait in it, never the entrance.
- One register everywhere, different levels per volume, some volumes at zero.
- Card on each machine, one sheet for the building, one named person who owns it.
One register, a written level plan, and the rooms that sit at zero
The register question on this page has a one-word answer - one - and the interesting part is why, because the reasoning is different from the usual argument about brand consistency.
Pick one of the seven water-based Hotel Collection registers and run it in every volume that is scented at all. Each is SOSA's own hotel-inspired interpretation, and SOSA is independent and not affiliated with, endorsed by or connected to any hotel brand. For a day-care hospital the field narrows to three, for the reasons this bank keeps arriving at: Quiet Luxury (white tea, bergamot, cedar) is hushed and polished and the safest single decision for a very mixed public; White Tea Serenity (white tea, aloe, cedar) is clean and weightless and reads as clean rather than as scented; Forest Suite (cedarwood, vetiver, green leaves) is grounding and green and reads as structural rather than decorative. Tea Garden and Warm Welcome want more care and a lower level again, and Old-World Glamour and Lobby Bar are the wrong shape for this building at any setting - plush reads as covering in a clinical space, and pepper announces itself in a room where somebody is waiting for news.
The reason one register matters more in a multi-level plan than in a single-room installation is the doorway. When two volumes run different levels of the same register, crossing between them reads as a change of quietness, which is what a building naturally does and which nobody notices. When two volumes run different registers, crossing between them reads as a change of place - and because the family in a day-care hospital crosses these thresholds repeatedly during one morning, the change is sampled over and over. A difference that would be invisible to a hotel guest passing once becomes the most noticeable thing in your building to somebody who has walked from the lounge to the counter five times since eight o'clock.
There is a second, more practical reason. A level plan with one register has one variable per room and is legible on a single sheet. A level plan with two or three registers has two variables per room, twice as many things to get wrong at a refill, and a real chance that somebody tops up the lounge unit with the reception bottle. If you are running an ultrasonic in one room and planning a Vaayu in the connected front of house, say so on WhatsApp before you buy, because those are two different fragrance systems - the Vaayu and the ducted machines run four hotel-inspired waterless blends supplied with the machine as one of three bundle choices, and the ₹299 water-based bottle never goes into them.
And what I will not do is rank the seven on measured throw or longevity in order to suggest one of them suits a low-level zone better than another. SOSA does not publish that comparison and it would be dishonest to imply it. Your levels are decided by cubic metres, enclosure, dwell and air exchange, and those swamp any difference between blends.
| Scent | Why it suits the mood |
|---|---|
| Connected front of house · one volume, one level | Entrance, counter and open lounge with no doors between them: 1,500 sq ft at 12 ft is 18,000 cubic feet, about 510 cubic metres. One register, one level, set by the four-hour wait rather than the four-minute counter visit. It will read faint at the threshold during the morning rush, and that is correct - the doorway person was never the one who minds. |
| Enclosed lounge behind a door · lower | A 600 sq ft lounge at 12 ft is 7,200 cubic feet, about 204 cubic metres, and a shut door means far less dilution than an open front of house gets from its automatic doors. Same register, a visibly lower level, set seated after forty minutes rather than from the doorway. Judge it on a Friday of a busy week, because fabric seating accumulates. |
| Small private room · lower still, or off | 180 sq ft at 10 ft is 1,800 cubic feet, about 51 cubic metres - a quarter of the enclosed lounge. Start at the bottom of the machine's range; if the bottom is still too much, the machine is wrong for the room and a reed diffuser from ₹749 is the answer. Its occupant is also the person least likely to tell you it is too much. |
| The clinical half and the holding area · zero, written as rooms | Pre-operative areas, procedure and operating rooms, post-procedure and post-anaesthesia recovery, sterile and decontamination areas, clinical and drug storage, clinical waste - nothing at all, not a lower setting. Usually the patient holding area beside the procedure doors too. Write it as a named list owned by the clinical and infection-control leads, who may extend it but not have it reduced. |
So the buying answer, which is usually one machine rather than several. Count the volumes first, then size each one.
For a connected front of house of about 510 cubic metres - the 1,500 sq ft at 12 ft example - the waterless SOSA Vaayu at ₹11,999 is the commercial answer and is comfortably sized, being rated for approximately 1000 cubic metres of connected air with SOSA's own copy also stating 2,000 to 3,000 sq ft scented evenly. In a healthcare building its defining features are what it does not do and what it lets you control: cold-air nebulising of undiluted oil means no water, no humidity and no wet residue, which is why a facility with a surgical zone will consider it where it will not consider a tank; and the Bluetooth app and timer mean the schedule is set once and runs your OPD hours rather than living in somebody's memory. 400ml tank, freestanding or wall mount, DC 12V / 1A at 5W and mains powered so it needs a live socket, CE, RoHS and SGS. It is an ambient fragrance product for public areas - not a medical device, not an infection-control or air-treatment device, not validated for clinical use - and it cannot travel through a closed door, which is precisely why the level plan works.
For a smaller connected front of house, an ultrasonic is usually the whole purchase: a SOSA Sukoon at ₹1,899 for a reception and billing area, a SOSA Boond at ₹899 for a single small enclosed room, or a SOSA Megh at ₹3,499 with its 6 litre tank for a large lounge running from seven in the morning to eight at night. All three take the water-based Hotel Collection from ₹299, with 100ml refills at ₹999 and a pack of seven 15ml bottles at ₹1,799 for testing registers in your own air. The ducted machines - Aangan at ₹25,999 for approximately 8,000 to 10,000 sq ft and Meenar at ₹38,500 for approximately 12,000 to 18,000 sq ft - are engineering decisions taken with your own HVAC consultant, and a scenting unit is never ducted into air handling that serves a clinical zone.
And the anti-drift purchase worth considering seriously: in any enclosed room where the level should be very low, a SOSA reed diffuser from ₹749 removes the dial from the building altogether. No plug, no noise, no timer, nothing for a well-meaning supervisor to nudge, about 6 to 10 weeks from a bottle, 130ml from ₹1,249 and refills at ₹2,399 for 300ml and ₹3,499 for 500ml. Mountain Breeze at ₹849 and Morning Freshness at ₹749 sit closest to a healthcare register, with Garden Bloom at ₹799 and Evening Calm at ₹799 softer and more associative, and Fresh Brew at ₹849 the wrong shape for a hospital.
Three siblings worth reading next. The arithmetic behind "the private room gets less, not more" is worked through in should VIP patient lounges in private hospitals have ambient fragrance. If any of your volumes borders the recovery corridor, the six leak paths - and the honest answer when the layout will not hold a boundary - are in how to scent an attendant lounge without fragrance spreading toward recovery areas. And if the single register is still undecided, the dwell-and-mixed-occupancy case for a lounge is in what fragrance direction suits a premium hospital lounge.
What SOSA does not publish and this page will not invent: consumption rate, refill frequency, monthly running cost, machine lifespan, minimum order quantity or installation lead time. Send your floor plan with the doors marked - and an honest note about which of them actually stay shut - to WhatsApp at +91 96192 18531. Bulk orders are welcome, custom label or logo on product is available, and bespoke composition is a real SOSA service discussed there rather than priced on a page - though the cheaper honest answer comes first, which is that one of the seven registers held consistently already is a signature, because consistency makes a signature and uniqueness does not.
The SOSA scenting range
SOSA sells two different systems and one of the commonest mistakes is mixing them up. Size by the connected air volume of the room you are actually scenting - which in a day-care hospital is almost always the entrance, reception, billing and attendant lounge alone - floor area multiplied by ceiling height gives cubic feet, and cubic feet divided by 35.3 gives cubic metres. A door that stays shut ends one volume and begins another.
| Machine | System | What it is for | Price |
|---|---|---|---|
| SOSA Boond | Ultrasonic · water-based | A small desk or corner unit for one enclosed room - runs the water-based Hotel Collection | ₹899 |
| SOSA Sukoon | Ultrasonic · water-based | A larger ultrasonic for a reception or consultation room - Hotel Collection from ₹299 | ₹1,899 |
| SOSA Megh | Ultrasonic · 6L tank | A large-tank ultrasonic for a bigger lounge that runs all day | ₹3,499 |
| SOSA Vaayu | Waterless cold-air nebulising | The commercial machine - approx 1000 m3 of connected air, Bluetooth app and timer, no water and no humidity | ₹11,999 |
| SOSA Aangan | HVAC nebulising | Ducted scenting for approximately 8,000 to 10,000 sq ft | ₹25,999 |
| SOSA Meenar | HVAC nebulising | Ducted scenting for approximately 12,000 to 18,000 sq ft | ₹38,500 |
Two systems, and they are not interchangeable. The ultrasonics - Boond, Sukoon and Megh - run the water-based Hotel Collection from ₹299. Vaayu and the HVAC machines run waterless nebulising oil; the ₹299 water-based bottle never goes into a Vaayu. SOSA blends are SOSA's own hotel-inspired interpretations and SOSA is independent and not affiliated with any hotel brand. A portion of every order supports girl-child education through Nanhi Kali.
- Vaayu ₹11,999 - waterless cold-air nebulising, approx 1000 m3 connected air, Bluetooth app and timer, 400ml tank, freestanding or wall / HVAC mount, DC 12V / 1A, 5W, mains powered, CE / RoHS / SGS.
- Aangan ₹25,999 for approximately 8,000 to 10,000 sq ft and Meenar ₹38,500 for approximately 12,000 to 18,000 sq ft - both ducted into HVAC.
- The ultrasonics - Boond ₹899, Sukoon ₹1,899, Megh ₹3,499 - run the water-based Hotel Collection from ₹299, with 100ml refills at ₹999.
- Not published, and therefore never stated on this page: consumption rate, refill frequency, monthly running cost, machine lifespan, installation lead time or any minimum order. Those go to WhatsApp +91 96192 18531.
Versailles
A day-care hospital is the most careful room I write about, and I want to be plain about why. Somebody walks in at seven in the morning to have a procedure. Their mother or their husband sits in your lounge for four hours with nothing to do but look at the walls and worry. And a few metres away, behind doors that should stay shut, there is a zone where none of this belongs at all.
So the answer here is not a stronger machine or a cleverer scent. It is a boundary. Entrance, reception, billing and the attendant lounge are the public half of your building and they are allowed to feel like somewhere that was thought about. Pre-op, procedure, recovery and everything clinical are the other half, and the honest answer for all of it is nothing. Not less. Nothing.
Two things I say to every facility that asks. Fragrance adds scent - it never subtracts one, so it cannot cover disinfectant, and a scent laid over disinfectant makes a third smell that reads worse than either. And the decision is not mine or yours alone: what is introduced into the air of a building with a surgical zone belongs to your clinical leads, your infection-control team and your engineers. I would rather lose the sale than have a page of mine used to argue past them.
Frequently asked questions
Facts verified September 2026: SOSA Vaayu ₹11,999 is a waterless cold-air nebulising diffuser rated for approximately 1000 m3 of connected air, with Bluetooth app and timer, a 400ml tank, freestanding or wall / HVAC mounting and a DC 12V / 1A, 5W mains supply. SOSA Aangan ₹25,999 covers approximately 8,000 to 10,000 sq ft and SOSA Meenar ₹38,500 approximately 12,000 to 18,000 sq ft, both ducted into HVAC. The ultrasonic machines - Boond ₹899, Sukoon ₹1,899 and Megh ₹3,499 - run the water-based Hotel Collection fragrance from ₹299, with 100ml refills at ₹999; that water-based bottle is not used in a Vaayu or an HVAC machine. Reed diffusers start at ₹749 and last roughly 6-10 weeks. A coverage rating assumes one connected body of air; scent does not travel through a closed door. Ambient scent research supports improved evaluations of a space and its service, longer dwell and stronger recall at moderate effect sizes - it does not support claims about bookings, fees or retention. Fragrance adds scent and does not remove, neutralise or purify odour, and no SOSA product makes any health, antibacterial or air-purifying claim. No SOSA product is a medical device, a clinical product, an infection-control product or an air-treatment device, and none is validated for use in a clinical environment. Nothing in this guide is clinical, infection-control or engineering advice: in a facility with a surgical or procedural zone, what may be introduced into the air is governed by the operator's own clinical leadership, infection-control policy and facilities engineering, and their decision overrides every recommendation here. SOSA blends are SOSA's own hotel-inspired interpretations; SOSA is independent and not affiliated with any hotel brand. Prices and availability are subject to change - see the live product pages.