Accrued expenses (Details) - USD ($)	Feb. 29, 2016	Feb. 28, 2015
Payables and Accruals [Abstract]
Accrued compensation	$ 305,189	$ 214,071
Estimated warranty costs	38,250	36,000
Accrued commissions	172,461	207,236
Professional fees	51,492	51,765
Other accrued expenses	178,644	182,865
Total accrued expenses	$ 746,036	$ 691,937