Name the gas which is used for fumigation of plant specimens once in year?

Question

Name the gas which is used for fumigation of plant specimens once in a year?

Answer 1

Almirah and segments in which herbarium are kept also protected from insects by spraying DDT, Naphthalene balls etc. once in year all herbarium sheets are fumigated by CS₂ (Carbon disulphide) in closed room or box