MAINTAINABILITY DESIGN TECHNIQUES METRIC - AcqNotes.com

Downloaded from http://www.everyspec.com on 2011-10-29T14:56:01.DOD-HDBK-791(AM)Figure 6-19. Character Height for Viewing Signs at Extended Distances (Ref. 4)4. Smallest label for individual components. displays,and controls.Label should be compatible with the expected viewingdistances. However, to provide discriminable differencesamong label sizes, each label character height should be atleast 25% larger or smaller than the next function label.Fig. 6-20 illustrates this hierarchy.6-5.4 METHOD OF APPLICATIONMethods of application together with their advantages,disadvantages, legibility, and permanence are discussedin par. 6-4.6-6 COLORS FOR LABELS AND SIGNSColor combinations of printing and background shouldbe selected to maximize legibility. The best color combinationsin descending order are given in Table 6-2.If color codes, labels, and signs are necessary, selectcolors on the basis of recognizable differences. the colorsindicated in Table 6-3 are ideal for surface coding becausethey are easily recognizable by both normal and colordeficient observers. when related displays and controlsare color coded, they should be coded the same color. allemergency controls should be coded in red.Color coding for hose, pipe, and tube lines for aircraftand missiles should be in accordance with par. 5.1.1,MIL-STD-1247 (Ref. 9). Color codes for pipelines shouldbe in accordance with par.4, MIL-STD-101 (Ref. 10).Caution and danger signs should be color coded asdescribed in par. 6-5.3.1 and illustrated in Figs. 6-16 and6-17, repectively. Signs indicating a radio frequencyradiation hazard should be coded as indicated in fig. 6-21(Ref. 24). signs indicating a nuclear radiation hazardshould be coded as shown in fig. 6-22.6-14