Occupational Safety, Animal Welfare and Environmental Aspects
Domain 9 links plant and farm safety, animal welfare and environmental control. Questions may ask for hazard controls, the five freedoms or waste-treatment options.
Core rules
- Use PPE, machine guards, lockout-tagout, safe chemical storage and ammonia-leak procedures.
- The five freedoms cover hunger/thirst, discomfort, pain/injury/disease, fear/distress and natural behaviour.
- Dairy waste includes dung, urine, whey and wash water; whey has high BOD and must not go directly to drains.
- Manure can be composted or digested for biogas; effluent needs treatment before discharge. Zoonoses include brucellosis, tuberculosis and leptospirosis.
Worked example
Four cows produce about 10 kg dung each per day = 40 kg/day. At about 0.04 m³ biogas per kg dung, potential biogas = 40 × 0.04 = 1.6 m³/day. The reasoning is that biogas yield scales with volatile solids in dung; the figure is an estimate, not a guarantee.
Traps
- Discharging whey to a drain causes serious organic pollution.
- Animal welfare is not only feeding; it includes comfort and natural behaviour.
- Ammonia refrigerant leaks are a major plant hazard.
- PPE is useless if it is worn incorrectly.