This control measure should be read in conjunction with Hazardous materials: Substance identification.

Biological agents can be found almost everywhere, however, general hygiene is sufficient to deal with the majority of situations (See Control measure - Decontamination for biological agents). At any location where there is foul or dirty water, waste materials, body fluids and human or animal waste, it should be considered that a biological agent may also be present. Establishments that have biological agents will be marked with the appropriate signage and will incorporate additional control measures such as security, access restrictions, ventilation systems and specialist/technical staff.

Biological agents may be encountered in a wide range of situations:

• Hospitals, e.g. isolation wards, post mortem areas, medical schools
• Veterinary practices, quarantine kennels, abattoirs
• Laboratories and research establishments
• Farms, zoos, wildlife parks
• Sewers, sewage treatment plants and flood water
• Post offices and mail delivery couriers
• Funeral parlours/embalmers

Biological agents can also be encountered in transit. Transport categories are defined as:

• Category A – an infectious substance transported in a form that can cause permanent disability, life-threatening or fatal disease to humans or animals if they are exposed to it
• Category B – an infectious substance that does not meet the criteria for inclusion in Category A

For all substances a ‘triple packaging system’ is used. This includes:

• A primary, watertight and leak-proof receptacle surrounded by sufficient absorbent material to absorb any spills caused by breakage
• Secondary, watertight and leak proof packaging, again containing sufficient absorbent material to absorb any spills
• Outer packaging that protects the secondary packaging from physical damage

The outer wrapping of any package should bear the international warning signs with a warning that the package should be neither opened nor touched. On the outer packaging there should be an indication of the nature of the contents, together with the name and address of both the consignor and consignee. These details should also be included on the package itself.

For transportation, infectious substances will be assigned to UN 2814, UN 2900 or UN 3373. Vehicles used for the transportation of Category A biological substances will display the orange placard and relevant warning diamond.

Postal delivery

Group 3 and 4 materials must not be sent through the postal system. Special arrangements apply to their transportation, nationally and internationally.

Diagnostic samples and Group 2 materials may be transported either by post or an authorised courier provided they comply with the packaging requirements and bear the international warning signs together with the names and addresses of the sender and recipient.

Organisations that regularly send such materials through the post should have procedures in place for contacting competent personnel in the event of an accident.

Location and meaning of signs

Establishments will display the international biohazard sign within the building. However, the use of this sign varies considerably. Other black and white signs may relate to animals (e.g. ‘Do Not Remove’, ‘May be Removed in Cages’ etc.).

Where biological agents are present within a building there should always be a warning symbol at the entrances to laboratories and refrigeration units for agents of hazard Groups 2, 3 and 4, but they may not be found externally

Biological agents are often transported on the road and sometimes in  private vehicles. In these cases, a safety officer familiar with the hazard will be on call to deal with any incidents.

Location and meaning of signs

Many establishments will display the international biohazard sign. However, the use of this sign varies considerably. Other, black and white, signs may relate to animals (e.g. ‘do not remove’, ‘may be removed in cages’).

If there are biological agents in a building there should always be a warning symbol at the entrances to laboratories and refrigeration units for agents of hazard groups 2, 3 and 4, but the signs may not be found on the outside of the building itself.