Primary standards are set to protect human health. Secondary standards are set to protect public welfare and take into consideration such factors as crop damage, architectural damage, damage to ecosystems, and visibility in scenic areas.

A primary confluence is one that meets the primary goals of the project, that is, it is on (or close to) land, and not ruled out by the "Poles Problem" restrictions. Check out "What is a primary confluence" above for more details on this. A confluence that is on (or close to) land, but ruled out by the Poles rule is called secondary. Confluence points of this type will be accepted if visited but are not part of the primary goals of the project. See similar questions...

One of the purposes of the Clean Air Act is to set NAAQS for each criteria pollutant. The Clean Air Act established two types of NAAQS. Primary standards are designed to establish limits for protecting public health, including the health of people particularly sensitive to air pollution such as young children, the elderly, and those with asthma or bronchitis. See similar questions...

A primary market, or "the issuing market", is where a security is issued and sold for the first time, either when a company issues capital shares on incorporation and sells them to founders or other investors, or when new shares are issued and sold in a period following incorporation for capital increase. Securities can also be put for sale to a specific group of investors, which is called "private placement". See similar questions...

Any collectible still being produced, or that is a current item, is considered to be on the primary market. A collectible that has been retired or discontinued and, therefore, is no longer available on the primary market, is considered to be on the secondary market. See similar questions...

There can only be one primary server. As for the secondary servers, you can have as many as you want: the information they have about your zone will be replicated from the primary server. See similar questions...

The distinction of primary from secondary amenorrhea is of little value in determining the cause for the amenorrhea. It does help doctors use a "word" shorthand to give a patient's history. A woman who has never had a spontaneous menstrual period has primary amenorrhea by definition. One who has ever had any spontaneous bleeding has secondary amenorrhea. See similar questions...

A.) RSH Web Services actually has three name servers. Although for registering or transferring domains ending in .com .net .org and 95% of all other domain names only two are needed See similar questions...

Primary brain tumors originate in the brain itself. Primary brain tumors do not spread from the brain to other parts of the body, except in rare cases. Pathologists classify primary brain tumors into two groups: glial tumors (gliomas), and non-glial tumors. Gliomas are composed of glial cells, which include astrocytes, oligodendrocytes, ependymal cells, Schwann cells, microglia, and satellite cells. See similar questions...

Good question! Most people equate Master with Primary and Secondary with Slave. In reality, the two are not quite the same. Primary name servers are the default name server (the first server that will be queried) based on how you have configured your domain's NS records with your registrar. Secondary name servers are the backup if the primary name server fails. Master and slaves refer to a management arrangement used within DNS servers to propagate information changes from one server to another. See similar questions...

The Primary Beneficiary is the first person or entity you want to receive the proceeds of your accounts. There can be more than one primary beneficiary, for example you could name. The secondary beneficiary is the second person or entity you want to receive the proceeds of your accounts should the primary be deceased or not meet specific serviceable qualifications you have instructed. There can be more than one secondary beneficiary just as the example above appears. See similar questions...

Some researchers believe that RLS may be related to dopamine, the chemical that carries signals among the nerve cells that control movement. Some research has shown that half of the time primary RLS can be traced to a family history. Secondary RLS only occurs as a result of an underlying medical condition such as iron deficiency, end-stage renal disease, pregnancy or diabetes. MIRAPEX is not indicated for the treatment of secondary RLS. See similar questions...

To improve reliability, DNS service for a domain is typically provided by multiple DNS servers: one primary DNS server and one or more secondary DNS servers. The difference between primary and secondary DNS is one of administration. The administrator of the primary DNS controls what names exist in the domain by configuring the DNS resource records for the domain, while the secondary DNS server(s) copy the domain's records from the primary server via an automated process known as a zone transfer. See similar questions...

Primary advisors are the organization's first contact for guidance and will oversee the finances of the organization (i.e., signing for expenditures and receiving financial statements). The secondary advisor serves as back up for the primary advisor. A secondary advisor is not required to become recognized. See similar questions...

With secondary coverage, you may be required to pay a deductible and may be asked to exhaust coverage from your other existing polices before filing a claim. All Travelex plans offer primary coverage. This means you'll never need to pay a deductible or file a claim with other providers. File with Travelex first and file once. See similar questions...

Mixing reduces the temperature of updrafts. The temperature of updrafts is rarely more than a few degrees more than that of the ambient air because mixing increases with temperature difference. Mixing of dry ambient air with air containing condensed water has a very strong cooling effect on the updraft because of the re-evaporation of the condensed water. See similar questions...

Primary drug of abuse is the drug type that caused the most dysfunction, and secondary drug is the drug type (if any) that has resulted in a lesser degree of dysfunction than the primary drug of abuse. The drugs of abuse categories are alcohol, marijuana/hashish, cocaine/crack, opiates, amphetamines, sedatives, inhalants, hallucinogens, over-the-counter drugs, and others. See similar questions...

Indoor Air Quality (IAQ) refers to the effect, good or bad, of the contents of the air inside a structure, on its occupants. Usually, temperature (too hot or too cold), humidity (too dry or too damp), and air velocity (draftiness or motionlessness) are considered "comfort" rather than indoor air quality issues. Unless they are extreme, they may make someone unhappy, but they won't make a person ill. See similar questions...