A sheet of aluminum foil is enough to block beta particles.
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Chinese uses 甲乙丙 ('first, second, third') instead of α β γ in nuclear-physics naming: 甲种粒子 = alpha, 乙种粒子 = beta, 丙种粒子 = gamma. The 甲乙丙 system is the same one used for naming oil grades and 'Plan B' (乙方).
