Generating evidence during a crisis: Setting standard for re-usable cloth masks in Zambia

June 15, 2020

Community woman wearing a mask

Written by Nampaka Nkumbula, Head of Experimentation; Roselyne Mwila, Head of Exploration and Salome Nakazwe, Head of Solutions Mapping

Like most Accelerator Labs across the globe, we were working on one of our four key services to debunk the waste management challenge in Lusaka. The long-awaited experimentation was becoming a reality with the team busy exploring different ideas on how the final stage of the learning cycle would play out. Suddenly, the world was at a standstill with the eruption of the novel Corona virus (COVID-19), which was declared a global pandemic by the World Health Organization (WHO) on 11 March 2020. This major public health emergency across the world results in a shift in priorities in all sectors of the economy, development activities that could not be implemented remotely were indefinitely postponed, uncertainty is becoming the new norm, everyone and everything has paused.

As governments across the globe explored any means to fight the COVID-19, a consensus on the positive impact of wearing masks has started building up resulting in the promotion of the use of masks by the population in many countries. With the potential of causing shortages of medical masks for frontline health workers, alternative ways of producing non-medical masks were sought to supply the general public and help reduce the exposure to the virus.

In Zambia, the Government announced the mandatory wearing of face masks in public as an effort to slow down the spread of the virus particularly in instances that do not permit social distancing or staying at home in parts of the city that cannot afford to shut down( News Diggers, 2020).

About 54.4% of Zambians live below the poverty line of USD 1.90/ day (LCMS, CSO 2015) and the average cost of surgical masks increased during the pandemic range from ZMW2.00 to the range of ZMW20.00-25.00, slightly below the 1.90 USD mark. This implied that most Zambians would not afford to buy medical masks. As in other countries, the use of non-medical re-usable cloth masks could be used as an alternative solution. However, a thorough literature review revealed that there was little evidence to justify the use of cloth masks from locally available materials on the Zambian market.

Despite this lack of evidence, “COVID-preneurs” ( entrepreneurs that fight COVID-19) were already taking advantage of the lack of clear guidelines by making trendy homemade masks from locally available materials. With no readily available standards or approved guidelines, this posed a potential risk as some materials and designs used to make the masks would create a false sense of protection. For example, some designs offered little coverage and some masks varied in terms of how many layers of cloth were used.

As we struggled to assess and fit our workplans to be virtually compliant, we had a light bulb moment. We discovered a missing link- a gap in information that could be used to provide guidelines on the use of local materials as reusable masks for community use.

The experiment: Two ingredients for a healthy experiment

(i)Strong rationale

To be effective, most masks need to adhere to three properties. These properties include filtration efficiency, breathability and fabric integrity. Although there is a standard testing procedure, there is no laboratory in-country carrying out such tests. The prescribed standard testing protocols also require prescribed apparatus/equipment to use. However, in the absence of the standard testing protocol, the Department of Chemistry of the University of Zambia (UNZA) designed a non-standard protocol that can provide an indication of the efficacy of the fabric.

The aim of our experiment was to assess the suitability of seven  different local fabrics; 100% cotton 200 thread count; 100% Cotton 180 thread count; Egyptian cotton; 100% cotton chitenge; Poly cotton chitenge blend, java wax chitenge and telela chitenge; for making facemasks by testing  the extent to which the selected clothing materials are able to prevent particles of a specified size passing through the fabric; to determine the ease with which air is able to pass through the fabric materials and finally to assess the effect of washing and heat treatment (ironing) on  the first two parameters.

(ii) Diverse Partnerships that offer multiple perspectives

We partnered with the University of Zambia Chemistry department and the Ministry of Health (MoH) to test the materials along 3 parameters, filtration efficiency, breathability and fabric Integrity.  Both partners presented a balance of finding that optimal point between speed of delivering the required evidence and need and use  for evidence that would be generated- a scaling partner.

The next step was to conduct solution safaris  and talked to some tailors who had already started producing cloth masks to find out what was happening in the communities.  The safari was set out to understand the types of materials they were using and their capability of large scale production. We found that most tailors could produce at least 50 masks per day. For masks sold at a retail cost of ZWM 25  and if it can be used over a period of 1 month, this would imply a saving of almost ZMW 575/ month.

So, what did we learn?

The following key learnings were made in line with the results obtained from the study:

(1)    Facemasks need to be made of 100% cotton materials that are more than 180 thread count.

(2)    The facemask needs to be made using at least two layers of cloth to increase their efficacy.

(3)    A combination of different types of cloth material may be used to achieve both high levels of efficacy as well as comfort in breathing. Fabrics with large pressure drops (ability to resist air passing through) will generally need the wearer to put in more effort in breathing, especially for a tight-fitting mask. For example, using a surgical mask as reference material that experienced a pressure drop of 0.002, the recommended fabrics had a pressure drop of in the range of + 0.02 bars which was close to the surgical mask’s reading and were considered easier to breathe in.

(4)    It should, however, be noted that pre-conditioning and post-treatment such as washing may affect the characteristics of the fabrics. Due care must be taken in choosing the cloth material avoiding materials that may change characteristics after washing such as those containing wax.

It is important to take into consideration the availability of cotton fabrics with higher thread counts as these tend to be more expensive and can have an impact on the pricing of masks. Notwithstanding these investigations, it is advisable that the intended use of fabric not originally meant for breathing system filters as stipulated under ISO 23328-1:2003 (en) conditions to qualify filters must be used with other guidelines. This will ensure increased safety and reduced risk of exposure to the virus particles in any of the droplet sizes.

It is important to underscore the fact demonstrated by research that cloth masks do reduce the risk of exposure, particularly by reducing the risk of transmission from an infected individual wearing a mask. That being said, the use of masks are not a standalone intervention and should be implemented with other preventive measures such as practicing social distancing by staying at least 6 feet away from other people when in public, staying home as much as possible, and thoroughly washing hands for more than 20 seconds or hand sanitizing with an alcohol based hand sanitizer(CDC, 2020; WHO, 2020).

Going full cycle

The results of the study were disseminated to the Ministry of Health, WHO and other partners that are supporting government’s response to COVID-19. The Accelerator Lab learning cycle is still ongoing and is branching out into different streams; on one end further tests are ongoing to evaluate the life span of cloth masks as they are subjected to successive washing, assessing the filtration efficiency using smaller particles and the efficacy of a combination of fabrics. Furthermore, the AccLab team is simultaneously supporting the country office to design guidelines for wearing, handling and care of the cloth masks by the general public, with additions being made as more evidence is generated.