Selection of masks
Mask is an object normally worn on the face, typically for protection, disguise, performance, or entertainment. Masks have been used since antiquity for both ceremonial and practical purposes, as well as they are usually worn on the face, although they may also be positioned for effect elsewhere on the wearer’s body. a covering made of fibre or gauze and fitting over the nose and mouth to protect against air pollutants, or made of sterile gauze and worn to prevent infection of the wearer or (in surgery) of the patient it is a a covering for all or part of the face, worn as a disguise, or to amuse or frighten others.
Classification of masks:
- Based On function
Surgical face mask
Particular Respirators( This is most suitable for Protection against bacteria and Viruses)
- Based on Usage
Low barrier mask with comfortable tie-on laces suitable for procedures with low levels of spray and splatter such as fluoride treatments, minor orthodontics and basic lab work construction and materials providing adequate protection and comfort. Single pleat design prevents fluid pooling and cross contamination non-woven inner layer for superior protection adjustable nose piece and tie-on for comfortable fitting. Extra long laces fit with a variety of facial shapes and sizes. Comfort Mask are basic masks which is used for Dust and large partials. These are used in dusty environment it protects from wet droplets which are present in environment. This mask is a 7″ soft, clean mask secured with ear loops intended for use in a clean room environment. This moderate barrier fluid resistant disposable surgical facemask combines high filtration with comfort and breathability.
Surgical face mask:
Surgical face mask:
A Surgical mask is a loose-fitting, disposable device that creates a physical barrier between mouth/nose of wearer and potential contaminants in the immediate environment. It also prevents patients from direct transmission of infectious agents from health care professionals these type of masks are not PPE as defined under European Directives for PPE
Spun bonded Non woven fabric
- Raw materials:
– Polyethylene terephthalate (PET)and polypropylene.
- Bonding method:
– Thermal bonding or resin bonding
– Bonding should be throughout the web
– Soft on skin
– Air permeable
– Water proof
– Can be sanitized
– Easy to stitch
- GSM Range: 15 – 30
The typical respiratory rate for a healthy adult at rest is 12-20 breaths per minute a 70 kg human breathes 20m3/day. This shows the importance of air purification in human life. air pollution from dust is an essential threat to human health. the process of removal of dispersed particles in the air by the porous medium is called filtration dispersed particles may be solids or liquids, whereas the dispersing medium may be gas (mostly air) or liquid nonwovens are the basic material used for purifying air from aerosol impurities in the form of solid or liquid particles. The porous media used in the filtration process are differentiated by structure, which can be fibrous, granular, and capillary.
Types of Respirators:
Types of Respirators:
- Valved Respirators
- Classification of Respirators
- FFP1 respirators – Suitable for lower filtering efficiency and protection factor.
- FFP3 respirators – For highest levels of filtering efficiency and protection factor.
- Removes contaminants from the air
- Particulate respirators
- “Gas mask” respirators
- Provides clean source of air
- Supplied air respirators (SAR)
- Self-contained breathing apparatus (SCBA)
- The following notations are called for respirator description.
- – N – Not Resistant to Oil
- – R- Somewhat Resistant to Oil
- – P- Strongly Resistant to Oil (Oil Proof)
- N95 respirators remove at least 95% of airborne particles with a size of 300nm (0.3 micron)
- N99 respirators remove at least 99% of airborne particles
- NI00 respirators remove at least 99.97% of airborne particles
Testing and Evaluation of Mask and Respirators
|Bacterial filtration efficiency 3STM F2101
|Breathing resistance (∆P) BSEN 13274- 3 – 2001 & EN 143
|Splash resistance (ASTM F1862-07):
|Flammability (16 CFR 1610):