Medify Air MA-40 Air Purifier – H13 True HEPA – 99.9% Particle Removal – 370 CADR (White, 1-Pack)

1 (one, unit, unity) is a number, numeral, and glyph. 1 is the first and smallest positive integer of the infinite sequence of natural numbers. This fundamental property has led to its unique uses in other fields, ranging from science to sports, where it commonly denotes the first, leading, or top thing in a group. 1 is the unit of counting or measurement, a determiner for singular nouns, and a gender-neutral pronoun. Historically, the representation of 1 evolved from ancient Sumerian and Babylonian symbols to the modern Arabic numeral.

In mathematics, 1 is the multiplicative identity, meaning that any number multiplied by 1 equals the same number. 1 is by convention not considered a prime number; this was not universally accepted until the mid-20th century. In digital technology, 1 represents the "on" state in binary code, the foundation of computing. Philosophically, 1 symbolizes the ultimate reality or source of existence in various traditions.

Year 370 (CCCLXX) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Augustus and Valens (or, less frequently, year 1123 Ab urbe condita). The denomination 370 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

40 or forty commonly refers to:

• 40 (number)
• one of the years 40 BC, AD 40, 1940, 2040

40 or forty may also refer to:

99 may refer to:

• 99 (number), the natural number following 98 and preceding 100
• one of the years 99 BC, AD 99, 1999, 2099, etc.

CADR may refer to:

• CAR and CDR, a programming language construct used in Common Lisp or Scheme
• CADR, the name of a computing system developed at M.I.T.; see Lisp machine
• Clean Air Delivery Rate, a rating system developed for portable room air cleaners
• Continuous Adiabatic Demagnetisation Refrigeration, a multi-stage magnetic refrigeration system
• Center for Alternative Dispute Resolution, an institution that provides training and accreditation

HEPA (, high-efficiency particulate air) filter, also known as high-efficiency particulate absorbing filter and high-efficiency particulate arrestance filter, is an efficiency standard of air filters.

Filters meeting the HEPA standard must satisfy certain levels of efficiency. Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard) or 99.97% (ASME, U.S. DOE) of particles whose diameter is equal to 0.3 μm, with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm. HEPA filters capture pollen, dirt, dust, moisture, bacteria (0.2–2.0 μm), viruses (0.02–0.3 μm), and submicron liquid aerosol (0.02–0.5 μm). Some microorganisms, for example, Aspergillus niger, Penicillium citrinum, Staphylococcus epidermidis, and Bacillus subtilis are captured by HEPA filters with photocatalytic oxidation (PCO). A HEPA filter is also able to capture some viruses and bacteria which are ≤0.3 μm. A HEPA filter is also able to capture floor dust which contains bacteroidia, clostridia, and bacilli. HEPA was commercialized in the 1950s, and the original term became a registered trademark and later a generic trademark for highly efficient filters. HEPA filters are used in applications that require contamination control, such as the manufacturing of hard disk drives, medical devices, semiconductors, nuclear, food and pharmaceutical products, as well as in hospitals, homes, and vehicles.

In the physical sciences, a particle (or corpuscule in older texts) is a small localized object which can be described by several physical or chemical properties, such as volume, density, or mass. They vary greatly in size or quantity, from subatomic particles like the electron, to microscopic particles like atoms and molecules, to macroscopic particles like powders and other granular materials. Particles can also be used to create scientific models of even larger objects depending on their density, such as humans moving in a crowd or celestial bodies in motion.

The term particle is rather general in meaning, and is refined as needed by various scientific fields. Anything that is composed of particles may be referred to as being particulate. However, the noun particulate is most frequently used to refer to pollutants in the Earth's atmosphere, which are a suspension of unconnected particles, rather than a connected particle aggregation.

Purifier(s) may refer to:

• Air purifier, a device that filters pollution out of the air
• Water purification, removing contaminants from water, sometimes using a water purifier
• The Purifiers, a 2004 action film
• Purifiers (Marvel Comics), a fictional terrorist organization

Removal may refer to:

• Removal (band)
• Removal jurisdiction in the United States courts
• Deportation, the legal removal by a government of a foreign citizen from its territory
• Removal of a child from its parents and placement in foster care by a child protection agency

Removal may also indirectly refer to:

• Administrative removal in immigration law
• Amputation, removal of a body extremity by trauma or surgery
• Deforestation (forest/tree removal)
• Enucleation of the Eye (eye removal)
• Hair removal
• Hedgerow removal
• Hidden-line removal, computer graphics
• Indian removal, the early 19th century United States domestic policy
• Manual placenta removal
• Removal services for moving house
• Removal of Internet Explorer
• Rib removal
• Penectomy (penis removal); see also emasculation
• Snow removal
• Stock removal
• Under cover removal
• Wire removal

True most commonly refers to truth, the state of being in congruence with fact or reality.

True may also refer to:

White is the lightest color and is achromatic (having no hue). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully reflect and scatter all the visible wavelengths of light. White on television and computer screens is created by a mixture of red, blue, and green light. The color white can be given with white pigments, especially titanium dioxide.

In ancient Egypt and ancient Rome, priestesses wore white as a symbol of purity, and Romans wore white togas as symbols of citizenship. In the Middle Ages and Renaissance a white unicorn symbolized chastity, and a white lamb sacrifice and purity. It was the royal color of the kings of France as well as the flag of monachist France from 1815 to 1830, and of the monarchist movement that opposed the Bolsheviks during the Russian Civil War (1917–1922). Greek temples and Roman temples were faced with white marble, and beginning in the 18th century, with the advent of neoclassical architecture, white became the most common color of new churches, capitols, and other government buildings, especially in the United States. It was also widely used in 20th century modern architecture as a symbol of modernity and simplicity.

According to surveys in Europe and the United States, white is the color most often associated with perfection, the good, honesty, cleanliness, the beginning, the new, neutrality, and exactitude. White is an important color for almost all world religions. The pope, the head of the Roman Catholic Church, has worn white since 1566, as a symbol of purity and sacrifice. In Islam, and in the Shinto religion of Japan, it is worn by pilgrims. In Western cultures and in Japan, white is the most common color for wedding dresses, symbolizing purity and virginity. In many Asian cultures, white is also the color of mourning.