Occupational Safety, Health and Environment
Occupational Safety, Health and Environment
This domain tests safe telecom work and environmental responsibility. Expect questions on electrical isolation, personal protective equipment, battery handling, fire response, e-waste and ergonomic and RF hazards.
Core rules
- Isolate and lock off power before work; test for dead with a proving unit; treat conductors as live until proven otherwise.
- Use PPE matched to the task: insulated tools, gloves, eye protection, footwear and hearing protection where required.
- Battery rooms need ventilation, no naked flames, acid-resistant PPE and correct spill procedures. Lead-acid batteries can release hydrogen.
- Use the correct fire extinguisher: CO2 or dry powder for electrical fires, never water.
- E-waste such as old routers, batteries and cables must go to authorised recycling, not general refuse.
Worked example
Before replacing a rectifier in an exchange battery room, isolate the AC and DC supplies, lock the isolation point, verify zero voltage at the terminals, and wear acid-resistant gloves and eye protection. Check that the replacement is rated for the DC bus and that polarity is correct before reconnection. After the work, remove tools, restore ventilation, and record the test results. The reasoning is that a battery bank remains energised even when the charger is off, so proving dead at the actual terminals is essential.
Traps that cost marks
Assuming low-voltage telecom lines are harmless; bypassing a lockout to save time; using water on an electrical fire; storing batteries in a damp unventilated cupboard; and discarding e-waste with ordinary rubbish.