HEPA filters for Dental clinics

HEPA filters and their types:

 

It is the time that we need to upgrade our dental clinics with the most sophisticated and most needed instruments that our patients can feel safer than anywhere else.  The overwhelming reports are suggesting that dentists are more prone to catch a COVID-19 infection from their day to day practice. It is possible to maintain your hand hygiene properly. It is probable to guide your patients accordingly that you can reduce the chances of getting contaminated from an asymptomatic carrier. But it is always a doubt to breathe free within your chamber once you are done with your work. 

Potential risk of SARS-CoV2:

As the researchers are publishing their articles regarding the spread of Corona virus, it suggests that mostly these viruses are capable of infecting other hosts as an airborne droplet or aerosol. Recent studies show that the stability of this virus is variable depending upon different materials and conditions. To judge the stability of SARS-CoV2 on different areas there is a study published in The New England Journal of Medicine. In that study they have compared SARS-CoV2 with SARS-CoV1 by evaluating their stability in air and four different surfaces. This study also shows the estimated decay time for these 2 different viruses.

According to this study the data shows the estimated half-life of the virus SARS-CoV2 (in TCID₅₀)

Material/Half-life (Hrs)	Median	2.5%	97.5%
Air	1.09hrs	0.64hrs	2.64hrs
Plastic	6.81hrs	5.62hrs	8.17hrs
Steel	5.63hrs	4.59hrs	6.86hrs
Cardboard	3.46hrs	2.34hrs	5hrs
Copper	0.774hrs	0.427hrs	1.19hrs

 

This data profile (described partly) clearly shows the airborne nature of this virus and the contamination procedure similar to that of SARS-CoV1. This indicated that the cross contamination may occur from other factors and also from the viral loads in the Upper Respiratory Tract of a potential COVID-19 infected person while being asymptomatic.

 Our ventures are always confined within the bilateral buccal walls. The patient will be without masks for a longer period in the clinic for their treatments. This potential time frame will cost a lot of aerosol inside the clinic. Additionally if we perform any AGP then the virus will be abandoned in the air and other surfaces. Using different surface cleaning agents, and maintaining a good hand hygiene can reduce the risk of getting infected. But the air is the reason to cause the damage if not cleaned.

Windows and doors with a good cross-ventilation are good for keeping pollutants away from the room. But inside a clinical setup the air can confine a lot of bad stuff that may damage your health. According to Environment Protection Agency, a study suggests that some pollutants are often 2-5 times higher indoors than outdoors.

Air filters are an essential equipment now?

Completely depends upon your need and resources. The best way to improve indoor air is to remove the pollutant source and to ventilate with clean outdoor air. Air-purifiers can help when these methods are insufficient or not possible.

Types of Air purifiers??

There are many technologies incorporated in an Air purifier to clean indoor air. Some of them are pretty handy and good to use and some of them are little complicated with a higher price range but not somewhat effective as it claims.

Mechanical Filters: here comes the HEPA filter. It uses a fan to push the air through a dense mesh of fibers which can trap the particles. Filters with the finest mesh are HEPA filters, provided it must collect 99.97% of pollutants up to 0.3microns.  

Activated Carbon Filters: While processing the air rather than catching the particles from the air, some air purifiers’ offer sorbent filters. Activated carbon filters can absorb some gases and make the air odor free.

Ozone generators: This purifiers or air sanitizers can produce ozone which will react with certain pollutants and change their molecular structure to make them inactive. Ozone purifiers are not recommended inside the clinic for some adverse effects of it.

Electronic Air purifiers: Electrostatic precipitators and ionizers charge particles in the air and thus the pollutants or harmful substances get stuck on the plates of the machine by magnetic attraction. This is also under consideration for recommendation as these machines often produce Ozone as a byproduct.

Ultra-Violet Germicidal Irradiation (UVGI): Some production houses claim that their air purifiers can kill virus, bacteria or fungus with the help of UV lamps. But it is not always as effective as it claims. Some of the bacteria and viruses are resistant to UV radiation

Photocatalytic oxidation: PCO or PECO filters use UV radiation along with a photocatalyst that can produce hydroxyl radicles to clean the air. Free hydroxyl radicals are harmful for the pollutants but also become harmful for us as they produce a good number of harmful by products.

Now comes the safest and the cheapest way to purify your indoor air is by HEPA filters.

 What is a HEPA Filter?

HEPA stands for High Efficiency Particulate Air filters.

During 1940’s US Department of Energy developed a defined standard for the HEPA filters to contain the spread of particles generated by the nuclear testing.

The HEPA standard as defined is the filter must remove 99.97% or more particles in the air which are 0.3microns in diameter. 

As it defines if 10,000 molecules of 0.3micron diameters pass through the HEPA filters only three of them must pass through.

 

Check for this, HEPA type or HEPA like filters.

Many of the manufacturers produce air purifiers that do not follow the standard of HEPA filters. To be in the competition they just print on the labels “HEPA-like” or “HEPA-type” air purifiers. This is nothing but just to confuse the consumers and provoke them to purchase low graded cheaper air purifiers.

Be safe from these labels and manufacturers. There are no other types of HEPA. Either it is HEPA or NotHEPA.

Medical Grade HEPA:

There are no different types of HEPA filters. But HEPA filters are categorized on the basis of their efficiency. A standard better quality True HEPA filter ranges from H10-H12.

HEPA H13-H14 are considered as the highest tier of HEPA filters and thus categorized as MEDICALGRADE HEPA FILTERS.

H10-H12 HEPA filters can trap 85% of particles ranging in 0.1microns. But, H13-H14 filters trap 99.995% of 0.1micron particles.

While purchasing your air purifiers do consider these facts before ordering. A H10-H12 HEPA filter purifiers is efficient for home but not at your dental office.

 

Other considerations while purchasing an air purifier for your Dental office…

 

The primary point to be considered is the cost of replacement filters. It’s a general rule to change the filters after every 6-8months. In case of Activated Carbon filters you need to change the filters every 3-4months. Some of the air-purifiers are incorporated with an indicator that will let you know the efficiency of the core filter.

You must look at the certifications of the product. You must check the Energy Star logo of the product as it must run around the clock to give you better results. Also look for the official certification for consumer electronics.

CADR: CADR or Clean Air Delivery Rates is the volume of air that a purifier produces on its highest speed settings. Any purifier with a CADR of less than 250 is not at all worthy enough for a dental office.

Check for the suggested room size listed on the label. Some of the Air purifiers don’t show such efficiency as they mention in their labels. But always consider the purifiers that are suitable for larger rooms (>350sq ft)

Check for the noise decibel of the air purifier. Some of the purifiers are too noisy at their highest performance which can be a bit annoying inside the clinic. Check for the noise produced mentioned on the labels

Features you must look for

1)       Washable pre-filters. It’s the reusable filter that contains larger particles before the main filter. This potentially increases the life of the main filter and saves a lot of money.

2)       Filter service indicator. This indicated the life efficiency of the main filter.

3)       There must be an air quality sensor which can evaluate the pollutants in the present air and can automatically adjust its cleaning speed accordingly.

4)       Remote control features. Recent models are also coming with smart app controls that you can adjust the purifier using your mobiles. Few of them have the feature of voice control via Google assistant or Alexa. This is a very useful feature for us to adjust the purifier settings on voice command while working on a patient.

Some of the Air-Purifiers meet the standards as it mentions in their description are as follows.

 

According recent reviews with the most advanced features one of the most popular air purifiers available in India are  

1)       Sharp Air-purifiers: Model No. FP-F40E-W.
>It claims to clean the indoor air up to 99.97%.

        >It is manufactured by a Japanese company. The servicing availability is yet not judged but the company has confirmed the supply of spare parts and consumables till the product is discontinued in India.

        >It gives a Dual Protection filter system to clean the air at its best. The air goes through a pre filter and then crosses the granular active carbon filters to the main HEPA filter. This model uses the highest available HEPA filter H14.

         >The exhaust is unique in design and covers the room with a 20 degree air flow.

         >MRP of the product is 15,900/- but in amazon you can get better deals.

         >The inefficiency of this product is in CADR. The value of CADR ranges from 200-250 CMH. This is pretty low for a larger dental office >200 sq ft. The company though claims that due to the high efficiency of this product it can serve up to 320 sq feet area.

> It also uses a plasmacluster ion generator as an additional feature to clean the air. They have certification from different labs that mention free from any byproducts due to the ion generators.
>There is no remote facility.
>The fan speed can be adjusted up to 5 levels.
>It has a special feature called Haze mode for better performance in Indian Climate. 
>It also has a sensor for dust particles.
>It produces 49 decibel of noise at its highest speed.
>Company provides 1 year warranty including spare parts and labor. 

 

3)       Mi Air Purifier 3: AC-M6-SC
MRP is 12,999/- varies on amazon and flipkart.
>It is a 3^rd Generation air purifier with smart app features.
>It uses true HEPA filters for cleaning the air up to 99.7%. It uses 380 degree air intake and 3 layers filtration.
>It has OLED touch display which shows real time air quality, Humidity and temperature.
>The coverage area is 484sq ft.
>CADR of this machine is 380CMH
>Controls are by touch screen or mobile app.
>It can be controlled by Google assistant and Amazon Alexa.
>Noise level is pretty high for this machine and may range up to 64 decibel which is quite annoying in a dental office.
>Company provides 1 year warranty excluding filters.
>Servicing from Mi Company is not such efficient as it should be.

 

4)      Phillips AC2887/20
>MRP is 22,995/-. Discount depends upon amazon and flipkart.
>It uses HEPA-type filters, with activated carbons.
>CADR value ranges from 200-333 cmh.
>Noise produced is around 51decibel.
>It uses AreSense Technology with real time display.
>Buying an additional FY2420 Nano Protect Activated carbon filter will cost 1550/- extra.
>Reviews are good but not recommended for dental offices.

 

5)      Phillips AC3256/20
>MRP is 32,995/-. Discounts available on amazon and flipkart.
>It uses 3 layers air filtration system with H13 HEPA filter and Activated carbon filter.
>It incorporates VitaShield IPS with aerodynamics design that uses an extra thick nanoprotect HEPA filter to clean the air up to 0.02micron particles.
>It has proven its efficiency in eliminating H1N1 virus.
>AreSense Technology indicator monitor.
>5 levels of fan speed adjustment.
>Controls are touch sensors.
>CADR value is 367cmh
>It can clean the air of 1024sq ft area.
>Noise produced is 63 decibel.

Sharp FP-J60

>MRP- 39,999. Check for discounts in amazon
>Dual action filter system. It uses H14 HEPA filter with Plasmacluster technology.

Sharp FP-J80

The Best Choice for a Dental clinic among the others economically and functionally.

>MRP 35,000/-, check for discount price in amazon.
>CADR is 480cmh
>Area coverage 650 sq ft
>Highly effective plasmacluster ion generator filters with H14 True HEPA filters and activated carbon filters.

Samsung AX7000
>MRP- 59,990/- check discount price at flipkart
>It uses 4 layers of filtration as pre-filter, deodorization filter, activated carbon, ionizer and HEPA filter./

>Coverage area is 1000 sq ft
>CADR: 773cmh
>Noise 54 decibel
>Sleek and professional design touch screen.

Benefits of Medical Grade Air purifiers

1) Eliminates the smallest airborne particles to give a safe and fresh air inside the clinic
2) Helps people with weak respiratory systems
3) They are mandatory now in the isolation rooms.
4) Helps in surgery rooms.

To get the best effects of an air purifier

1) Choose it wisely to get the best results.
2) Clean the filters accordingly as the company guidance mentions. 
3) Select a place to keep it wisely.
4) Keep the air purifier running the whole working time inside the clinic.

Few other options as an Air purifier in the dental office

Blueair 280i Digital HEPA-silent Air Purifier 
Samsung AX3000
TruSens Z2000
EurekaForbes Dr. Aeroguard 

Eureka Forbes Dr. Aeroguard SPR300

Posted by Dr. Arka Bhattacharya

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