Equipment may be electrically unsafe, explosion hazardous, radiation unsafe or environmentally unprotected. Safety cannot usually be built into equipment alone, but calls for a combination of measures extending also to installation rules and maintenance and application of the equipment. A number of isolated first faults may eventually cause a hazard. Faults are due to designs having an insufficiently large safety factor and lack of redundancy techniques or protective devices. Manufacturers and installers do not take into account a safety factor that not only allows for initial mechanical and electrical strength but also the effect of use and wear, production methods and transport and storage conditions.
Considering scientific laboratories in particular, their variety, size, type and complexity preclude simple generalizations on the health and safety of laboratory work. Laboratory workers are selected and employed primarily because of their specialized education, knowledge and skills, and not because of any qualifications related to health or safety interest. Unless the laboratory is intimately integrated with a manufacturing facility, the degree of regulation and control actually enforced is usually lower than that for production operations. In addition, there is a feeling which has been fostered by the academic community itself that little should be done to interfere with 'academic freedom', no matter how serious the consequence of that freedom. In addition, research laboratories in academic institutions and in government and industrial establishments are frequently at the frontiers of knowledge both of science and of hazards. For this reason, laboratory workers are often the first persons to be exposed to new chemical and physical dangers, and they may suffer unexpected injury unless effective control, monitoring and medical supervision are integrated into the planning of the laboratory operations.