This paper deals with estimation of primal panel data models of production risk, focusing on measurement of risk properties of inputs and productivity growth. Under production risk oneshouldestimatetechnicalchangeseparatelyforthedeterministicpartandriskpartofthe technology, since risk averse producers will take into account both the mean and variance of output when they rank alternative technologies. For a panel of Norwegian salmon farms fish feed and fish input are found to increase output risk, while labor has a risk-decreasing effect on output. In the analysis of technical change by the first order stochastic dominance criterion the increase in mean output dominates the increase in output risk.