Reusable DIY Cloth Mask with Disposable Middle Layer Filter
Kitchen Towel Paper
This website, diymask.site, aims at unofficial manual of HK Mask. This website does NOT endorse / parter any mask manufacturer/ reseller/ distributor to sell any masks.
此網站設立目的為HK Mask非官方說明書。 此網站並沒有與任何口罩廠合作/作出認可，從而銷售任何口罩。
HK Mask is a reusable cloth mask with a disposable middle layer filter. It was invented by Dr. K. Kwong during the outbreak of COVID-19 in early 2020.
The design of HK Mask is referred by that of 3-layer surgical mask in the market. The HK Mask is composited with a disposable middle layer filter which is sandwiched by a cloth mask as the outer and inner layers. There are a number of material chosen for the middle layer filter ranging from Kitchen Towel Paper to Nanofilter.
The filtration efficiency of a piece of kitchen towel paper is close to that of N70. The mask can be safely used after replacing a new middle layer filter to a cleaning and sterilizing the inner and outer layer cloth
HK Mask 為可更換中層濾芯及可重複使用的自製口罩，於2020年初新型冠狀病毒肆虐香港期間，由鄺士山博士（Dr. K. Kwong）主導研發。
I am Dr. K. Kwong, a scientist, an inventor and a KOL in HK, the creator of HK MASK, the Do It Yourself solution to save you!!!
Since the infection explosion of COVID-19 in China, we Hong Kong people, did the best to slow down the spreading of COVID-19 in Hong Kong. These actions are promoted by experts in medical fields and many many others (except Government officials). I am one of the KOL participated in the movement.
I hope the following measures (which are using in Hong Kong now) can help your motherland:
STOP social activities
that involve close contacts. At least 1.5 meter away from each other. Which means stop school activities, religious gathering etc. Home office is preferred.
with SOAP AND WATER FOR 30 seconds whenever you think your hands are contaminated
USE Alcohol Sanitizer
Use 60-90% alcohol-based (ethanol or isopropyl alcohol) hand sanitizer on contaminated skin
Disinfection with Bleach Solution
Use 1:99 Chlorine bleach (5% stock) to disinfectant other objects
If Bleach and Alcohol are not available (Out of Stock)
There are some other alternatives for disinfection, but basically SOAP, ALCOHOL, BLEACH work perfectly
Before completely disinfection,
Do not touch your eyes, nose and mouth.
Avoid going to indoors with the Crowded
e.g. Bars, Gyms etc. If you think you are infected, you must do SELF-ISOLATION FOR 14 DAYS.
Wear a Mask, even you don't have symptoms,
A 3-layer surgical mask is enough to prevent your droplets or others' droplets. If you can't get one, you can sew one with the design from HK Mask as shown below:
If you don't have MASK, you can do it yourself with a DIY solution:
HK MASK (basically a filter holder+a filter).
The FILTER can be two pieces of pocket tissue paper or one piece of kitchen tissue paper. The mask can be made of any fabrics, but the thinner the better.
About Filter 有關濾芯
Basic Knowledge of 3-layer Surgical Mask and how it protects you:
After proper testing, two pieces of Tissue papers from Tempo and a piece of kitchen towel paper can achieve respectively 69.6% and 73.7% filtration efficiency at 0.3 micron (the higher is better). i.e. Two pieces of tissue papers and a piece of kitchen towel paper ~ N70.
With the reasonable low pressure drop, 2 pieces of Tissues Papers and 1 piece of kitchen towel paper can be used in the DIY Mask.
Fold the fabric in half, place the paper pattern on the fabric, pin the paper pattern and cut it along the edge, and then remove the pin. (Remember: the shell fabric is cut according to the soild line; the lining is cut according to the thick dotted line); and mark the marks(notch hole and elastic placement) on the fabric.
Put the shell cloth face to face(right side to right side), stitch the centre front with the back stitch, and then open the seam.
Fold the top side of the shell cloth into the back 1 cm, put the wire in the right position, and use the return stitch to fix the folding position.
Fold the bottom side of the shell cloth into 1 cm, and use the stitches to fix the position of the hem.
Fold the bottom of the lining up and down into 1 cm, and use the back stitching step at the top and the stitching step at the bottom to fix the folding position.
Put elastics on both sides of the shell cloth. The position of the elastics must be placed on the side, and the position is fixed by about 1 cm with back stitching.
Place the top and bottom cloths facing each other,and fix the sides with the back stitches, then turn outwards.
Put the tapes in the side position between the two cloths, and sew the two cloths with the back stitch (beware to avoid sewing the cotton tape)
In the middle bottom of the mask stitch a small rectangle to stitch on 2 layers with needle steps, about an inch wide for fixing the filter. Sew on both sides of the wire （sew the shell fabric only) to secure the wire and not slide.