Note 5 - Accounts Receivable, Notes Receivable and Customer Concentrations

12 Months Ended

Dec. 31, 2012

Loans, Notes, Trade and Other Receivables Disclosure [Text Block]

5.    ACCOUNTS RECEIVABLE, NOTES RECEIVABLE AND CUSTOMER CONCENTRATIONS

At December 31, 2012 and 2011, our allowance for doubtful accounts amounted to $14,000 and $30,000, respectively. Net charges against the allowance for doubtful accounts were $1,000 and $8,000 in 2012 and 2011, respectively.

The following table indicates the percentage of consolidated revenue and year-end accounts receivable represented by each customer that represented more than 10 percent of consolidated revenue or year-end accounts receivable.

	Revenue						Accounts Receivable
	2012			2011			2012			2011
ChemFree
Customer A		13	%		11	%		13	%		13	%
Customer B		7	%		8	%		14	%		16	%
Customer C		27	%		27	%		20	%		28	%
Customer D		10	%		9	%		12	%		12	%