Note 10 - Activity of Business Segments - Consolidated Net Sales (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net sales	$ 11,282,000	$ 12,708,000	$ 22,032,000	$ 24,555,000
Building Supply [Member] | Operating Segments [Member]
Net sales	6,283,000	7,924,000	12,222,000	14,679,000
Disposable Protective Apparel [Member] | Operating Segments [Member]
Net sales	3,774,000	3,624,000	7,068,000	7,448,000
Infection Control [Member] | Operating Segments [Member]
Net sales	$ 1,225,000	$ 1,160,000	$ 2,742,000	$ 2,428,000