Guide to Worker Protection with Control Banding
Control banding (CB) is a validated risk assessment method, commonly used to evaluate chemicals. Control banding is used internationally as part of the ILO Chemical Tool Kit and the UK HSE COSHH Essentials. In North America we use control banding for Asbestos abatement and when working with materials containing respiratory crystalline silica. It was originally designed for Small and Medium-Sized Enterprises that lack industrial hygiene staff; however, we have seen large businesses use it as a force multiplier for their H&S teams. CB offers a time and cost-effective way to assess risk and determine relevant control measures to reduce exposures in workplaces when OELs or exposure measurements aren’t readily available.
How Does Control Banding Work?
Step 1: Sort Chemicals by Hazard Level
Our initial step involves categorizing our chemicals based on their hazard levels, allowing us to pinpoint highly hazardous substances, such as those linked to cancer, mutations, and occupational asthma.
As you can see by this chart, GHS classification Health hazard statements make this easier; high hazard chemicals are at the top as Hazard Band D and E. C are corrosive and less toxic as are Hazard Band B. And Hazard Band A are the least hazardous, reversible irritants. This chart uses HSE COSHH Essentials criteria for banding. NIOSH Tier I has a similar ranking.
Step 2: Apply Control Measures
Once chemicals have been ranked by hazard, we can apply the control measures by a range or “band” according to the risk.
Control Approach 1: Natural Ventilation
Control Approach 1 is appropriate for low-risk activities. It prescribes natural ventilation and good IH practices such as:
- Unrestricted access to fresh air
- Clean air flowing across breathing zone
- 5 air changes per hour
- Prompt spill cleaned up
- Processes in place to train and ensure exposure control measures are known and used and standard PPE such as coveralls, safety glasses and gloves
Control Approach 2: Engineering Controls
Control Approach 2 is appropriate for medium risk activities and prescribes all the previous measures including:
- Controls designed for task
- LEV with 0.5 m/sec at the contaminant source
- Enclosure of the contaminant if possible
- Annual Testing or the LEV: using a ribbon, smoke, or anemometer
Control Approach 3: Containment
Control Approach 3 is appropriate for high-risk activities and prescribes all the previous measures including:
- Material handling performed in closed systems with limited breaches
- Containment or isolation of workers or chemical leaks
- Negative pressure if possible
- Venting directed to safe area
- Work permits to open process vessels
Control Approach 4: Expert Advice & Containment
Control Approach 4 is appropriate for extreme risk activities and prescribes:
- Multiple control strategies,
- Exposure control plans,
- Often respirators are assigned making medical fitness necessary, some hazards like lead, asbestos and silica may require health surveillance of workers,
- Preventative maintenance programs are also part of this control approach
Summary of Controls by Hazard Type
This 5x3 risk matrix shows how the controls necessary for the task are applied to the type of hazard along the left hand side (i.e. eye irritant, corrosive, carcinogen,) and the exposure profile along the bottom (small, medium or large quantity, as well as volatility and dustiness).
Protect Workers & Assess Chemical Risks with Chemscape
Chemscape recognizes the importance of expert advice in managing chemical safety. Our approach ensures that even in the face of the most severe chemical risks, companies are well-equipped to protect their workers effectively. If you have questions about control banding, contact our team for support.