It is of no use if one has a policy which is not followed. Display of policy may create good impression to visitors. But, not following it will lead to poor culture leading to unsafe behaviors, accidents and will eventually pull down the organization's image.
It is said that a good safety culture means the way we work safely even when nobody else is watching. Our conscience is our witness. If we try fool others when we behave one way in front of others and the other way in the absence of others, finally we only get into accidents. It is our life that is at risk. One may get good pat on the back but we should pat ourselves that we are doing a good job.
Shell's 12 life saving rules can be found here. Though these are not exhaustive, but still these can save lives of workers.