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The collisional pumping of CH3OH and OH masers in non-dissociative C-typeshock waves is studied. The chemical processes responsible for the evolution ofmolecule abundances in the shock wave are considered in detail. The largevelocity gradient approximation is used to model radiative transfer inmolecular lines. We present calculations of the optical depth in masertransitions of CH3OH and OH for a grid of C-type shock models that vary incosmic ray ionization rate, gas density and shock speed. We show that pre-shockgas densities $n_{H,tot} = 2 \times 10^4-2 \times 10^5$ cm$^{-3}$ are optimalfor pumping of methanol maser transitions. A complete collisional dissociationof methanol at the shock front takes place for shock speeds $u_{s} \gtrsim 25$km s$^{-1}$. At high pre-shock gas density $n_{H,tot} = 2 \times 10^{6}$cm$^{-3}$, the collisional dissociation of methanol takes place at shock speedsjust above the threshold speed $u_{s} \approx 15-17.5$ km s$^{-1}$corresponding to sputtering of icy mantles of dust grains. We show that themethanol maser transition E $4_{-1} \to 3_0$ at 36.2 GHz has the optical depthhigher than that of the transition A$^+$ $7_0 \to 6_1$ at 44.1 GHz at highcosmic ray ionization rate $\zeta_{H_2} \gtrsim 10^{-15}$ s$^{-1}$ andpre-shock gas density $n_{H,tot} = 2 \times 10^4$ cm$^{-3}$. These results canbe applied to the interpretation of observational data on methanol masers nearsupernova remnants and in molecular clouds of the Central Molecular Zone. Atthe same time, a necessary condition for the operation of 1720 MHz OH masers isa high ionization rate of molecular gas, $\zeta_{H_2} \gtrsim 10^{-15}$s$^{-1}$. We find that physical conditions conducive to the operation of bothhydroxyl and methanol masers are cosmic ray ionization rate $\zeta_{H_2}\approx 10^{-15} - 3 \times 10^{-15}$ s$^{-1}$, and a narrow range of shockspeeds.

Modelling cosmic masers in C-type shock waves -- the coexistence of Class I CH3OH and 1720 MHz OH masers