Historically, safety cabinets, laboratory equipment and containment laboratories have been fumigated using formaldehyde. Methods have changed over the years and currently consists of boiling Formalin and water in purpose designed vapourisers.
Formaldehyde has many advantages, it is highly mobile and penetrative, reaching all areas of safety cabinets and laboratories and has a wide spectrum of biocidal activity.
Problems associated with it arise from:
Crowthorne Group’s policy is to avoid discharging formaldehyde after fumigation to remove the risk of re-entrainment or exposure of personnel in plant rooms. Chemical neutralisation also allows fumigation of recirculating cabinets and other laboratory equipment.
Hydrogen peroxide, developed for fumigation of isolators and cleanrooms where equipment can be placed throughout the area, is broken down into oxygen and water to avoid the need to discharge it. It is less mobile than formaldehyde, meaning leaks do not migrate as far, but presenting limitations in fumigation of containment laboratories. Its biggest disadvantages are costs and the need for more independent studies into its efficacy.
It is expected that formaldehyde will be banned within a few years pending that its use can continue with strict controls.
Formaldehyde fumigation of containment laboratories is less clear due to the limitations of alternative agents, especially under emergency fumigation conditions.
There are two schools of thought with respect to the type of equipment to use for hydrogen peroxide fumigation:
A complication is the EU Biocidal Products Regulations 2012, applying to all biocidal products, however the HSE have said ‘they are content’ for us to continue purchasing standard laboratory reagents for fumigation. This is not however a statement of law and is open to change.
To discuss fumigation further, please contact Steve Roberston at firstname.lastname@example.org.