21 is made to insure practical and enforceable regulations. The cooper- ation given by industry in the formulation of industrial standards is of tremendous value not only in the preparation, but in their en- forcement. APPROVAL OF DEVICES Another important duty of the Research Section is that of approving jevices. This work is divided into two parts. First, there are the jevices required to be approved by the regulations of the Department. [n other words, some parts of machines or equipment are considered so hazardous that the Department should control the types of guards placed on the machines. The regulations are, therefore, so written as to permit only approved guards to be installed on such machines or aquipment. The duty of approving the devices falls upon the Industrial Board, but this Board, through the very nature of its structure, must depend on some other agency to conduct the necessary investigations of such devices, and so refers them to the Bureau of Industrial Standards. The Research Section makes a complete study of the device to determine if it meets the requirements of the regulations, whether it is practical and dependable, and whether the reputation of the manufacturer is such as to guarantee that the device will continue to be manufactured ae- aording to specifications. The second type of approvals covers all other devices submitted to the Department in order that it may be in a position to advise indus- iries as to the practicability of the device and whether it will satisfac- torily perform the work it is intended to do. There is no legal backing to the approval and industries are not required to use such approved devices. The approval simply places the Department in a position of being able to tell inquiring industries where they can purchase a device that will satisfactorily take care of a particular guarding problem. The investigation procedure is the same as for Industrial Board ap- provals but no report of the investigation is made to the Board. Lists of these two classes of approvals are prepared by the Research Section and are available for distribution. GENERAL RESEARCH Realizing that the inspectors who have the duty of enforcing the regulations cannot be expected to interpret them to others as well as the organization that prepared them, this Bureau prepares, in the form of what is known as departmental bulletins, standard instructions con- serning the enforcement of the regulations, explanations of the mean- ing of particular rules, and illustrations of the methods of applying the rules to particular conditions. This work not only enables the inspector to give the industries in his district a proper explanation of the mean- ing of these regulations, but it insures that the inspection force labors as one man in its general enforcement work and in a way intended by the regulations. This Bureau also makes special studies concerning accident-preven- tion work for the purpose of preparing data that will be helpful to the industries of the Commonwealth, may be useful in supplementing regu- lations. or simply be of an advisory nature.