Tanks

Question 1

Is tank heating equipment fitted with a duplicate thermostat and high temperature limit device?

Answer 1

Any tank heating equipment should be fitted with a duplicate thermostat and high temperature limit device. The high temperature limit device should prevent the temperature of the liquid exceeding a temperature of 10°C below its boiling point. There should be a regular testing programme for the thermostats and temperature limit devices, with the results being recorded.

Question 2

Is any vessel containing internal heating elements fitted with a duplicate low-liquid-level alarm and cut-out to prevent the elements being exposed to the atmosphere, with provision being made for isolation of the system in the event of an emergency?

Answer 2

Any vessel containing internal heating elements should be fitted with a duplicate low-liquid-level alarm and cut-out to prevent the elements being exposed to the atmosphere. Provision should be made for isolation of the system in the event of an emergency

Question 3

Are vent pipes from storage tanks designed to release vapours so as to allow them to disperse safely?

Answer 3

Vent pipes from storage tanks should be designed to release vapours so as to allow them to disperse safely; this should be subject to a risk assessment in compliance with DSEAR. Normally, a discharge height of 0.3m above the top of the tank or at least 3m above ground level should be sufficient but there may be a need to increase this height to achieve effective and safe vapour dispersion. Vent outlets should be located so that vapours are discharged upwards or horizontally away from adjacent walls and clear of eaves and other obstructions.