Abstract: Provided is a method and metering system for the determination of active ions emitted from certain active substances such as rayon fibers containing fine particles of tourmaline known to exhibit permanent spontaneous polarization. The method comprises: continuously bringing air free from carbon dioxide as a carrier gas into contact with a bed of the active ion-emitting source material to carry off the active ions emitted therefrom; introducing the air after contact with the source material into distilled water; and measuring increase in the electric conductivity of the distilled water caused by the absorption of the active ions from the flow of the air as a carrier gas. The metering system comprises: a feed source of the non-ionic inert gas; a sample holder to contain the source material emitting active ions; a vessel containing distilled water to receive the air carrying the active ions; a means to determine the electric conductivity of the water; and pipelines connecting these parts for the flow of air.

Abstract: Proposed is an electret fiber which is an insolubilized polyvinyl alcohol fiber containing 0.05 to 0.5% by weight of tourmaline particles having a particle diameter not exceeding 0.3 .mu.m. The electret fiber is effective for invigoration of human body by promoting blood circulation and also effective for decreasing the BOD value of sewage water by activating the bacteria in the activated sludge. The electret fiber is prepared by spinning a spinning solution of the polyvinyl alcohol containing the tourmaline particles into the form of a fiber which is then subjected to an insolubilization treatment by a heat treatment, formalization with formaldehyde or acetalization with glutaraldehyde.

Abstract: Proposed is an electret fiber which is a rayon fiber containing 0.05 to 2.0% by weight of tourmaline particles having a particle diameter not exceeding 0.3 .mu.m. The electret fiber is effective for invigoration of human body by promoting blood circulation. The electret fiber is prepared by spinning a spinning solution of rayon containing the tourmaline particles uniformly dispersed therein into the form of a fiber.

Abstract: Proposed is a fabric mattress having a layered structure as a kind of health-promoting bedding goods, which comprises an upper fabric layer, a lower fabric layer and an intermediate fabric layer sandwiched between the upper and lower fabric layers, at least a part of these fabric layers being formed from fibers such as rayon fibers containing very fine particles of tourmaline in an amount of up to 7% by weight. This unique ingredient in the fibers has an effect to emit active electrons and far-infrared light which exhibit an invigorating effect on the human body cells of the person lying on the mattress to promote blood circulation so that even a patient lastingly lying on the bed never suffers from bedsores by using the mattress which can be constructed to have good air permeation.