amber VOA / EPA vials online Sigma. EPA Vials - TOC Vials Manufacturer from Aala These EPA Vials are also referred to as VOA (Volatile Organic Analysis) vials EPA vials provideTwo sizes available in clear or aer neutral glass Standard 28 mm o.d. with heights of 57 mm (20 mL) and 95 mm (40 mL) Glass that meets ASTM Type I Class A. Get Price.