The International Labour Organization defines Control Banding as “a complementary approach to protecting worker health by focusing resources on exposure controls. Since it is not possible to assign a specific Occupational Exposure Limit to every chemical in use, a chemical is assigned to a ‘band’ for control measures, based on its hazard classification according to international criteria, the amount of chemical in use, and its volatility/dustiness.”1 The banding is then utilized to recommend four possible control strategies.
Below is an example of how control banding might be used with respect to nanomaterials:
Exposure Control
Exposure
Duration |
Bound
Materials |
Potential
Release |
Free /
Unbound |
Hazard Group A (Known to be inert)
|
|||
Short
|
1
|
1
|
2
|
Medium
|
1
|
1
|
2
|
Long
|
1
|
2
|
2
|
Hazard Group B (Understand reactivity/function)
|
|||
Short
|
1
|
2
|
2
|
Medium
|
1
|
2
|
3
|
Long
|
1
|
3
|
3
|
Hazard Group C (Unknown Properties)
|
|||
Short
|
2
|
2
|
3
|
Medium
|
2
|
3
|
4
|
Long
|
2
|
4
|
4
|
Exposure Duration Key: Short: < 4 hours/day, 2 days/week Medium: 4 to 6 hours/day, 3 to 5 days/week Long: 6 to > 8 hours/day, 3 to 5 days/week
Release Key: Bound: Nanoparticles in Solid Matrix Potential: Nanoparticles in friable or sol gel matrix Free/Unbound: Nanoparticles unbound, not aggregated
Control Band (Risk Level) Key: 1: General ventiliation and personal protective equipment (“PPE”) 2: Engineering controls and/or respirators, additional PPE 3: Containment (e.g., glove box) 4: Seek specialist advice
Please see the following resources for more information about the utilization of control banding with respect to nanomaterials: