  We discuss the consequences of the quantum uncertainty on the spectrum of the
electron emitted by the $\beta$-processes of a tritium atom bound to a graphene
sheet. We analyze quantitatively the issue recently raised in [Cheipesh et al.,
Phys. Rev. D 104, 116004 (2021)], and discuss the relevant time scales and the
degrees of freedom that can contribute to the intrinsic spread in the electron
energy. We perform careful calculations of the potential between tritium and
graphene with different coverages and geometries. With this at hand, we propose
possible avenues to mitigate the effect of the quantum uncertainty.
