- Increasing natural daylight levels in atrium type buildingsKoppel, Tarmo; Tint, Piia56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 154-155
- Microwave reflection properties of building materials in the working environmentKoppel, Tarmo; Haldre, Heldur56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 148-150 : tab
- Minimising radiofrequency radiation exposure of smart phones and tablets - using an off-line reader instead of wireless browsing for mobile learningAhonen, Mikko; Koppel, Tarmo56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 144-145 : tab
- Shielding inbound microwave electromagnetic radiationKoppel, Tarmo; Haldre, Heldur56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 151-153 : tab
- The new occupational electromagnetic fields' directive 2013/35/EU compared to the existing Estonian national legislationKoppel, Tarmo; Vilcane, Inese56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 156-158 : tab
- Voluntary safety management system in manufacturing industry - to what extent does OHSAS 18001 certification help?Paas, Õnnela; Reinhold, Karin; Tint, Piia56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 161-162