Surgical Masks....which side out? N95 or 3 Ply?

  • Which side of the mask should face outside?
    • The coloured side.
  • What if the mask is white on both sides?
    • Look for markings like brand names etc written, usually on the side facing out.
  • What if there are no markings, and I put it on with the WRONG side facing outward?
    • Keep calm and breathe easy. It'll still work (as far as surgical masks do) :) Surprised?

I have had a lot of people giving weird opinions on face masks recently. Some say that during haze, you need to wear the mask with the coloured side inside, whereas there are others saying that the coloured side should always face outwards.

This article aims to clear the haziness of the situation once and for all.

To understand how surgical masks work, you need to first know how they are made. And this is the trickiest part. After searching the web for various manufacturers and surgical mask designs, I noticed they are not universal in design. A lot of companies follow their own patented designs. Fortunately, the basic build up of the mask is still the same:


Non-Woven, Liquid-Resistant, Thermobond (varies), Poly propylene material



Non-Woven, Liquid-Resistant, Meltblown (varies), Poly propylene material DESIGNED AS FILTER MEDIA BARRIER


Non-Woven, Liquid-Resistant, Thermobond (varies), Poly propylene material. Some brands use AIR-LAID paper.

Even if you didn't understand a thing about the diagram up there, you'll at least notice the main points:

1. The outer and innermost layers are WATER RESISTANT (NOT FILTERING!), meaning to prevent saliva and mucous going OUT, and blood or other bodily fluids getting IN. If you're buying cheap 3 ply surgical masks, chances are these two layers are IDENTICAL. The "premium" masks with "Air-laid" paper some brands offer is just to make it feel softer to your skin, and possibly absorb more moisture than the rest. This is good when you are trying to prevent droplets from going out of the mask.

2. The MIDDLE layer, is the real filter layer. It filters particles and droplets BOTH ways, to prevent germs from the wearer from going OUT, and to prevent germs and droplets from outside to come IN contact with the wearer.

3. Of course if you can identify the proper side to be out or in, that will be best. Just don't fret too much if you don't ;)

 So the argument that during haze season, the white (or inner side of the mask should be outside) is TOTALLY invalid!

But wait, there is another popular belief going on.

The Singaporeans are saying that surgical masks are USELESS against the haze, as the particles can be as small as 100nm, and only the N95 masks can be of any use.

This statement, is half true. While nobody doubts that the N95 particulate filter is MUCH more efficient in filtering particles, there ARE a lot of points supporting the use of a surgical mask as well.

1. Surgical masks are not USELESS. They're just not as good as the N95s. Below is an Excerpt of the comparison done by 3M company between an N95 mask and a regular 3 ply surgical mask.

It basically means that if the surgical mask is of good quality, it may still be less than 70% effective when compared to the gold standard of N95 masks.

While we're not jumping for joy, 70% is not too bad when compared to zero percent protection from the haze! SOME protection is better than NO protection right? The FULL 3M comparison can be viewed at the end of this article.

2. N95 masks are only useful when FITTED RIGHT. And we mean 100% right. Below are some examples of the way MOST people wear their N95 masks.

This happened in our Sungai Ara Branch. A wealthy lady about the age of 60 walked in and wanted to buy MORE N95 masks. The picture above was how she was wearing the mask, with the entire nose above the mask. Needless to say, she was merely wasting good masks, and of course, wasting her money.

But even the "Professionals" get it wrong. Below are a few photos I grabbed from sites selling N95 respirators.



That "GAP", will have made this mask totally useless against the haze, or any other mater.  An N95 mask needs to be "test fitted" after being worn, and I can assure you 90% of our public won't practise this, or simply don't know this. The following pic is a simplified sample of how you should put your N95 mask on.

3. N95 masks make it HARD TO BREATHE (or at least harder to breathe). I have customers who take their masks on and off throughout the day just because they feel "Pening" or dizzy if they wear it for long periods of time. It takes some getting use to for people to really be able to endure N95 masks for the whole day. Trust me, it's not fun.

4. N95 masks are not cheap. Because they cost more, a lot of my customers tend to REUSE them. They just can't accept the fact that a mask that costs around RM6 can only be worn once, and chucked just like that. It's not going to be very affordable to a big portion of our population too. 

So in conclusion, N95 Masks are NOT BAD. They are in fact the best particulate mask that you can buy in a local Pharmacy. But if you're going to use it, make sure it Fits well, make sure you are able to Breathe well, and make sure you don't reuse it. If not, you'll still be better off with the 70% protection you get from a regular surgical mask.

by Lim Kelvin