The first criterion for using any suit that is designed to protect the body from the ingress of hazardous materials is to ensure that you full understand the hazard you coming into contact with. This will usually result in having studied the COSHH (Control of Substances Hazardous to Health) data sheet for the area or products concerned. This will then give you all of the data you need to make an informed decision.
Biological hazards are split into 4 groups and defined in the EU directive 2000/54/EC and should be studied to ensure that if you are facing a biological hazard you understand all of the risks.
- Risk Group 1: Biological agents unlikely to cause sickness to people. This is easily protected against.
- Risk group 2: Biological agents that could cause sickness to people but have little chance of dispersal outside of the area being worked in. Effective protection and measures are possible.
- Risk Group 3: Biological agents that could cause severe sickness to people and have a chance of dispersal outside of the area being worked in. This usually can have effective protection but the measures to ensure safety from dispersal are much greater.
- Risk Group 4: Biological agents that could cause severe sickness or death to people and have a high chance of dispersal outside of the area in certain circumstances. Effective protection and measures may not be normally possible.
There are many papers written on how biological substances occur and in which sectors. A full risk assessment will always lead you to the correct choice.
Protective clothing then has other categories and these cover how gas tight a suit may be, the pressure that is required to penetrate it, the time that certain bacteria’s may take to break through followed by penetration test tables. This covers all aspects from airborne particles to bacteria. All of these are listed under the protective clothing EU directive EN 14126:2003. These ratings are shown as shields and the higher the number the better the level of protection. So the standard paper overall that stops dust and other airborne particles that is regularly seen in use would be a 1 but this would be of little use to someone working in a chlorine cloud.
Good risk assessment usually stops simple mistakes from being made. Make sure you understand the protection level required. Does the whole body need to be covered. Do you have safe disposal if the suits that are contaminated after use. If you are unsure of anything seek specialist help.