The waste and recycling industry is re-making itself in response to changing needs and wants of our customer base, moving business segments from landfills and incineration to recycling and composting. As an example of these ongoing changes, the New York city council recently passed legislation requiring commercial food scraps from the largest food service establishments to be recycled (thousands of tons of food scraps diverted from landfills to composting). This new “commercial organic waste” policy is similar to state-wide policies requiring food waste recycling in Vermont and Connecticut and matched by initiatives in the cities of Austin, Portland, San Francisco and Seattle.
Responding to these needs and wants with new business models result in both “old” and “new” safety hazards that need to be addressed to protect workers. Many of the processes associated with composting are the same or similar to other processes in the waste and recycling industry. In many cases, the “old” safety hazards have been evaluated and reasonable responses have been identified throughout the industry, so it’s simply a matter of recommitting to established safety norms. Newly identified safety hazards specific to composting will need to be addressed along with the old:
- Transportation issues with vehicle movements, reversing and visibility issues, separation of people and machines
- Machinery, including system failures to control the risks associated with shredders, conveyors and bagging operations
- Falls during sheeting operations, slips and trips, including failure to control material spillages
- Occupational ill-health concerns that range from musculoskeletal injuries from manual handling to dermatitis caused by poor handling practices
- Primary human pathogens (viruses, bacteria, fungi, and cysts or eggs of intestinal parasites)
- Secondary pathogens and their toxins (spores and endotoxins generated by bacterial and fungal growth by the composting process)
- Corrosive, caustic or explosive materials
- Volatile and semi-volatile organic chemicals
- Persistent organic chemicals
- Metals, other inorganic materials and organometallics
- Allergens from household and yard wastes
The logical path toward dealing with newly identified safety issues (and in some cases for “old” safety hazards) would be to conduct risk assessments. Though conducted with uncertainty as a baseline, risk assessments can be generally straightforward. With MSW composting, the situation is further complicated by the complex nature of MSW and other materials with which it might be composted. The following are the steps that companies might take as they look at their safety process related to composting.
Depending on the particular operation, MSW composting workers may be exposed to a number of physical and chemical hazards, pathogens and toxic substances along with equipment and machinery.
Duration, severity and frequency are factors to be evaluated in assessing exposure, whether to a toxin or heavy equipment exposure to a pedestrian.
Once we have some knowledge of the distribution of potential exposures over time and some understanding of the outcomes from different types of hazard (exposure to a toxic bioaerosol, sickness, backed over by vehicle, death), the formal risk assessment of MSW composting and its products can be undertaken.
Risk assessment should identify solutions for the identified hazards (wearing respiratory protection when the potential of exposure to toxic bioaerosols exist, vehicles on site should always pull forward before backing up – giving pedestrians a signal and time to move out of the way).
The most effective means to communicate risks and solutions to affected parties should be chosen and implemented (orientation sessions, signs, training, video, brochures).
For an industry to survive in times of change, the industry must change.