Safety Measures For Inspection And Maintenance; Safety Measures For Work Inside The Tank - Graf oneAdvanced Operation Manual

2.4 Safety measures for inspection and maintenance

Do not consume any food or drink when operating or working at or on the plant.
Edibles coming into contact with microbes may carry and cause infection.
Shutting down the plant's installations and equipment.
Equipment may start to operate unexpectedly. Damaged wiring poses a risk of electric
shock.
Before all repair, maintenance, and cleaning work on the plant, shut it down
completely, including all of its installations, and secure it against reactivation.
Disconnect the electrical installations from their power supplies.
Only specialised electricians may be assigned to work on the electrical
installations and to connect the plant to its power supply.
Danger from electric shock.
Handle chemicals properly.
Chemicals can cause poisoning, harm to health, and caustic injuries.
Consult their manufacturers' safety data sheets for details.
Whenever necessary, wear PPE.
Keep chemicals safely away from children and unauthorised access.
2.4.1

Safety measures for work inside the tank

Harmful gases may form inside wastewater treatment systems. The wastewater may carry path-
ogens and substances harmful to health. The plant's tanks and shafts may be accessed bodily
for repair and maintenance work only.
Verify that work in the tank is necessary.
Always examine first whether this work may be performed from outside (e.g.
inspections with a remote controlled camera).
Assign a second person to supervise all work.
This second person must remain at the access point. He must remain in constant
contact with the person in the tank and be in a position to fetch assistance
immediately.
Never enter the tank without this second, supervising person.
Empty tank completely
An accident victim can also drown in shallow depths.
Never enter a tank, even when it is only partially full.
Provide a supply of healthy air to the tank.
Before being accessed, the tank must first be vented adequately to clear it of any
gases.
If adequate cross or diagonal venting (chimney effect) cannot be ensured, a supply of
air must be provided with equipment.
Whenever necessary, measure and monitor constantly the air quality.
2. Safety
12 / 137