Block Contamination Level
As a reminder, thousands-blocks contaminated up to and including 10 percent are eligible for
donation. Please refer to the definition of Contamination as outlined in the Thousands-Block
Number (NXX-X) Pooling Administration Guidelines (Section 14 - Glossary):
“Contamination occurs when at least one telephone number within a thousands-block of telephone numbers is not available for assignment to end users or customers. Blocks contaminated up to and including 10 percent are eligible for donation. For purposes of this provision, a telephone number is “not available for assignment” if it is classified as administrative, aging, assigned, intermediate, or reserved as defined in FCC rules (FCC 00-104, §52.7 (h)).”
Currently, California NPA 310 has been granted an exception to this rule (FCC 03-196). Thousands-blocks that are contaminated up to and including 25 percent are eligible for donation.
As a reminder, thousands-blocks contaminated up to and including 10 percent are eligible for
donation. Please refer to the definition of Contamination as outlined in the Thousands-Block
Number (NXX-X) Pooling Administration Guidelines (Section 14 - Glossary):
“Contamination occurs when at least one telephone number within a thousands-block of telephone numbers is not available for assignment to end users or customers. Blocks contaminated up to and including 10 percent are eligible for donation. For purposes of this provision, a telephone number is “not available for assignment” if it is classified as administrative, aging, assigned, intermediate, or reserved as defined in FCC rules (FCC 00-104, §52.7 (h)).”
Currently, California NPA 310 has been granted an exception to this rule (FCC 03-196). Thousands-blocks that are contaminated up to and including 25 percent are eligible for donation.