documentclass{article}
usepackage{scalerel,graphicx}
newcommandfuelpump{scalerel*{includegraphics{fuel_pump}}{strut}}
begin{document}
normalsize pump: fuelpump

LARGE or LARGE: fuelpump
end{document}

documentclass{article}
usepackage{fontspec}

newfontface{symbolafont}{Symbola}

newcommand{gaspump}{{symbolafontsymbol{"26FD}}}

begin{document}

This is the symbol for a gas pump: gaspump

end{document}