Protecting Yourself: Masks For Delhi's Air Pollution

As air pollution in Delhi continues to worsen, the importance of wearing the right mask to protect yourself from harmful pollutants cannot be overstated. While cloth and surgical masks were widely used during the COVID-19 pandemic, they are ineffective against small pollution particles that can enter the lungs and bloodstream. To safeguard your health, it is crucial to select a mask that fits well, has high filtration efficiency, and is certified by relevant authorities. So, which mask is good for air pollution in Delhi? Let's explore the options.

Masks to Combat Air Pollution in Delhi

N95 masks offer protection from small particulate matter

The N95 mask is a specialised type of protective mask designed to filter out at least 95% of airborne particles. Its designation means it has been certified to block a minimum of 95% of tiny (0.3-micron) test particles. N95 masks are constructed from multiple layers of synthetic material, typically polypropylene, which achieve a very close facial fit and efficient filtration of airborne particles.

While N95 masks offer protection from small particulate matter, they have some limitations. Firstly, they are designed for single-use or limited reuse. Extended use or improper handling can compromise their filtration efficiency. Secondly, N95 masks may not offer sufficient protection against certain gases and chemicals found in some pollutants. For example, gases such as sulphur dioxide, nitrogen dioxide, and ozone will pass through an N95 mask.

N95 masks are essential for frontline workers and those in environments with high particulate matter exposure, like construction sites. They are also crucial for vulnerable individuals during periods of hazardous air quality. For example, wearing an N95 mask can provide critical protection for individuals with pre-existing health conditions like asthma, chronic obstructive pulmonary disease (COPD), or heart disease during wildfire events.

To ensure the proper functioning of N95 masks, it is important to achieve a good seal with fit testing. The mask should have a clip over the nose to offer a proper seal, and adjustable straps, with one that goes over the head providing the best seal. It is also important to ensure the mask covers both the nose and mouth and fits snugly against the sides of the face without gaps.

Cloth masks are ineffective against small PM particles

Cloth masks are not effective against small PM particles. They are ineffective against pollutants like PM 2.5. The majority of cloth masks have a filtering efficiency of 3%, and they are ineffective in blocking small droplets and particles. Cloth masks with a filtering efficiency of 3% have a high infection rate, and healthcare workers wearing such masks were infected more often than those with masks with a higher filtering efficiency.

A study from Europe compared homemade cloth masks and surgical masks with N95 respirators. The results confirmed the superior efficacy of N95 respirators, but what was striking was the efficacy of surgical masks and homemade masks in reducing particle concentrations by 4-fold and 3-fold, respectively (compared with 100-fold by the N95 mask).

N95 masks can protect against particulate matter, but they cannot prevent exposure to gaseous pollutants such as sulphur dioxide, nitrogen dioxide, and ozone. N95 masks are the most widely used air pollution masks, removing up to 95% of non-oily allergens as small as 0.3 microns. N95 masks are washable and reusable.

N99 masks are considered more beneficial in fending off pollutants. They can remove up to 99% of particles as small as 0.3 microns. The N100 mask eliminates up to 99.97% of pollutants as small as 0.3 microns. It is a High-Efficiency Particulate Air (HEPA) mask with superior particulate filtration.

Therefore, cloth masks are ineffective against small PM particles, and N95 or N99 masks are recommended for protection against air pollution.

Respirators with activated carbon are efficient in filtering gases

The air quality in Delhi has been steadily worsening since 2021, with around 1.67 million deaths in India in 2019 attributed to air pollution. While the use of masks has increased due to the pandemic, cloth and surgical masks are ineffective against small pollution particles that can enter the lungs and bloodstream. Doctors recommend N-95 masks as they offer a good fit and protection against particulate matter when worn properly with no leaks. However, N-95 masks cannot prevent exposure to gaseous pollutants.

Respirators with activated carbon filters are designed to address this issue by removing harmful gases and vapours from the air through physical and chemical adsorption processes. Activated carbon, also known as activated charcoal, has a large surface area and pore structure that attracts and traps airborne contaminants, purifying the air and making it safe to breathe. This is particularly effective for toxic gases like COx, NOx, and SOx, which cannot be filtered by ordinary masks.

The effectiveness of respirators with activated carbon filters has been demonstrated in a study in West Kalimantan, Indonesia, where the community used respiratory protection with activated carbon to reduce exposure to toxic gases in the ambient air. The results showed that activated carbon, in combination with other materials like spunbond and meltblown, was more effective in absorbing toxic gases compared to surgical masks.

Activated carbon filters are also used in vehicles to protect passengers and drivers from harmful chemicals and unpleasant odours. These filters can remove various contaminants, including VOCs, SO2, formaldehyde, H2S, and ammonia.

When selecting a respirator with activated carbon filters, it is important to consider the specific contaminants and standards applicable to your situation. Different filters are designed for specific gases and vapours, and there are country-specific and military standards, such as MIL-SPEC or NIOSH CBRN, that dictate the performance criteria for respirator filters.

Surgical masks are not suitable for air pollution

Delhi's air pollution has been steadily worsening since 2021, and masks have become a winter staple in the city. However, not all masks are created equal when it comes to protecting against air pollution. While surgical masks may be effective in preventing the spread of germs or viruses, they are not suitable for protecting against air pollution. Here's why:

The primary reason surgical masks fall short against air pollution is their inability to filter out tiny pollution particles. Air pollution in Delhi, and many other cities, is largely composed of PM2.5, fine particulate matter that is about 1/30 the width of a human hair. These minuscule particles can easily pass through the loose-fitting surgical mask, infiltrating your lungs and even entering your bloodstream. As Intermountain Healthcare spokesman Jess Gomez explains, "a regular surgical mask won't do any good at filtering out particles because the PM 2.5 [...] is much too small."

Surgical masks are typically designed for use in sterile environments, such as operating rooms, to prevent the spread of bacteria and germs. They are not intended for use as respiratory protection against pollutants and lack the necessary filtration capabilities. The lightweight, porous material of surgical masks is simply not designed to capture the tiny particles present in air pollution.

Additionally, surgical masks often lack a proper seal around the face, allowing for inward leakage of air and particles. A study from China revealed that commercially available masks, including surgical masks, allowed for 3% to 68% inward leakage during sedentary tests. This leakage defeats the purpose of wearing a mask for protection against air pollution.

While N-95 masks are a more effective alternative, offering protection against particulate matter when properly worn, even they have limitations. N-95 masks cannot prevent exposure to gaseous pollutants like sulphur dioxide, nitrogen dioxide, and ozone. These gases can pass through the mask, and while activated carbon filters have been developed to address this issue, they are challenging to use consistently.

In conclusion, while surgical masks have their place in healthcare settings, they are not suitable for protecting against air pollution. The inability to filter out tiny pollution particles, the lack of a proper seal, and the absence of specialized filtration all contribute to their ineffectiveness. For individuals facing air pollution, investing in masks designed for particulate filtration, such as N-95 masks or certified microfibre masks, is a more prudent choice.

P95/P99/P100 masks are high-grade masks for strong protection

When it comes to tackling the hazardous levels of air pollution in Delhi, P95, P99, and P100 masks offer superior protection. These masks are designed to filter out a wide range of pollutants and provide a strong defence against airborne particles and gases.

The 'P' rating on these masks indicates their ability to filter out oil-based pollutants in addition to other particulate matter. The numbers 95, 99, and 100 signify the percentage of particles these masks can filter out, offering protection against 95% to 99.7% of harmful substances in the air. This makes them a reliable choice for individuals seeking maximum protection from the toxic air quality in Delhi.

P95, P99, and P100 masks are commonly used in industries such as petrochemicals and pharmaceuticals, where exposure to high levels of pollutants is common. While these masks offer excellent protection, they may not be suitable for daily wear due to their specialised nature and higher price point. However, for those seeking the highest level of protection, these masks are a worthwhile investment.

It is important to note that while these masks provide superior filtration, ensuring a proper fit is crucial for maximising their effectiveness. A good fit ensures minimum leakage of air from the sides, which can defeat the purpose of wearing a high-grade mask. A proper seal can be achieved by looking for masks with adjustable straps, including one that goes over your head, and a clip over the nose.

In conclusion, P95, P99, and P100 masks offer Delhi residents a robust defence mechanism against the city's severe air pollution. While they may be more expensive and less reusable than other options, their superior filtration capabilities make them a top choice for those seeking the highest level of protection from the hazardous air quality in Delhi.

Frequently asked questions