This letter considers the recent and practically relevant problem of safety in cyber-physical systems (CPS). Practical applications of CPS can be designed through the use of wireless multi-agent systems (MAS) since they provide flexibility and interoperability of the system functions. On the other hand, the performance of wireless MAS is prone to jamming attacks and the destructive effects of wireless channels. The aim of this letter is to determine safety bounds on wireless CPS under jamming attacks in the presence of additive white Gaussian noise (AWGN) and wireless fading channels. The impact of both wireless channel impairments and jamming attacks on the performance of wireless MAS has been investigated for the first time. The disagreement vector, defined as the deviation from the desired consensus value of MAS based on the quantization error, is analyzed and investigated for AWGN and fading channels. Theoretical results are supported by matching simulation results.