1.1 This specification covers requirements for first grade concentrated natural rubber latex (see Table 1) of the following types: Type 1-Centrifuged natural latex preserved with ammonia only or by formaldehyde followed by ammonia. Type 2 -Creamed natural latex preserved with ammonia only or by formaldehyde followed by ammonia. Type 3 -Centrifuged natural latex preserved with low ammonia with other necessary preservatives.

1.2 This specification is not necessarily applicable to latices prepared or preserved by other methods, and shall not be construed as limiting the desirability or usefulness of other types of latices. It does not apply to natural latex sources other than Hevea braziliensis nor to compounded latex concentrates.

1.3 The analytical procedures applicable to the specifications are included and appear in the following order: Sampling, Total Solids, Dry Rubber Content; Total Alkalinity, Viscosity, Sludge Content, Coagulum Content, KOH Number, pH, Mechanical Stability, Copper and Manganese, Density, Volatile Fatty Acids, Boric Acid, Dry Films, Precision for All Test Methods.

1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.