Abstract
Formaldehyde gas, generated by the depolymerization of paraformaldehyde and in the presence of water vapor, has been traditionally used for biological decontamination of equipment and spaces utilized for research with a susceptible biological agent. This gas has often been neutralized with ammonia gas, generated by the thermal decomposition of ammonium bicarbonate or ammonium carbonate. An elementary theoretical analysis indicates that for total neutralization the proper weight ratio of commercial ammonium bicarbonate to paraformaldehyde is 1.58, while that for ammonium carbonate to paraformaldehyde is 1.00 to 1.13. These values are supported by experimentation. The ratio for ammonium bicarbonate in particular is 44% greater than that advised in existing literature.