This Standard establishes values for safety distances to prevent access and distances to impede free access to machinery danger zones to prevent their being reached by the lower limbs of persons of 14 years of age and above.The values given are based on practical experience which has been found to be adequate for this group of persons.These distances apply when adequate safety can be achieved by distance alone, and when access by the upper limbs is not foreseeable according to the risk assessment.These safety distances will not provide sufficient protection against certain hazards, for example radiation and emission of substances. For such hazards, additional or other measures need to be taken.The safety distances to prevent access relate to openings, and serve to protect those persons trying to reach danger zones under the conditions specified for different reaching situations.The distances to impede free access relate to the height from ground level to the protective structure, and serve to reduce risk to persons by limiting the free movement of the lower limbs.If persons below 14 years of age are to be taken into account, it is not relevant to establish values other than those for upper limbs. In this case the safety distances to prevent danger zones being reached by the upper limbs, derived from AS 4024.1801 will apply.For certain applications, there are justifiable reasons to deviate from these distances. Standards dealing with these applications should indicate how adequate safety can be achieved.