1. Implement a two-keeper system with the dangerous animals, in particular the Sumatran tigers, at the zoo.

The two-keeper system could include strict procedures about cross checking by both staff that the gates are locked when required and the sliding gates in the ‘cat chute’ were closed when required.Further two keeper procedures could include that only one keeper is in charge and retains the keys required to lock the gates into position and that only one keeper (the one not in charge of the keys) would have the radio and/or mobile phone and would answer any calls received;

2. Keep the main keeper gate, a two gate system, in its original position at the entry of the cat chute gate into the enclosure.

This would mean that keepers are required to walk past the cat chute run before entering into the tiger enclosure. This then provides the keeper with a second chance to double check that the tigers have been contained in the off display tiger enclosure and the gates are closed before entering into the enclosure;

3. Paint the counter-weights on the cat chute sliding gates a bright colour.

This would have the effect of ensuring that at a glance the keeper can see whether the cat chute gates were up or down before entering into the tiger enclosure;

4. Fit mechanical interlock devices to all the gates, in particular the main keeper gate, at the tiger enclosure;

and

5. Erect signage at the keeper gates reminding keepers to double check that the tigers are secured.