The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
How To Design And Install Plumbing
This fact, however, does not lessen the importance of trap installations on a plumbing system. The properties, both physical and chemical, of the many gases found in sewage systems are known, and their effect on the human body is often serious. No individual could maintain health if he were required to breathe large quantities of hydrogen, hydrogen sulphide, methane, or carbon dioxide; and even a small amount of carbon monoxide in the atmosphere within a building may prove fatal.
Many of these gases are obnoxious, and, if not fatal when breathed by human beings, are nauseating and undesirable and may be a contributing element to lesser diseases of man.
The basic function of a trap on a drainage system is to prevent these objectionable gases from entering the plumbing system. Mechanics often are of the opinion that its purpose is much more extended and often expect the trap to do much more than it was designed to do.
Because of extreme conditions caused by simultaneous fixture use and overtaxed waste conditions, the plumbing system is subjected to minus and plus pressures which affect the liquid content of the trap. (This phase of the plumbing industry will be discussed in the next chapter under "Trap Seal Loss.") Traps consisting of movable internal mechanisms which form their seals were produced to overcome these difficulties. The principle of these devices is to form a mechanical barrier against the passage of sewer air. These various types of traps fail because of the effect the dissolved and suspended materials contained in the waste have upon them. The movable parts corrode readily and, in this condition, fail to operate. Most state authorities prohibit their installation for these reasons.
Traps also have been designed with internal metal partitions, which are subject to acid conditions of the waste. The object of this was to produce a device that would be compact and have a rather neat appearance. These forms of traps also have failed and should be discarded.
Today, sanitary authorities depend on, and design plumbing systems which use traps that have a water seal. Elaborate installation systems are essential to maintain a constant pressure of one atmosphere (14.72 lb. or 760 mm. ) to make these traps effective; but even though the cost tends to mount with this type of installation, it appears as though not much ever can be done about it. Spending to promote efficient trade practices or to maintain a high standard of health is true economy, and the more foolproof an installation can be made, so that the consumer need not fear contact with it, the greater its benefits.
