وسائل منع نفاذ الضوء خلال المدخل الرئيسي والنوافذ بمعمل التصوير .

Means of preventing light penetration through the main entrance and windows of the imaging laboratory:

Although the dark room or photo lab with one door (Fig. Therefore, many methods were designed to achieve the previous purpose, including that the entrance should have two bays that may be directly opposite each other (Fig. 113 - h).

Whereas it may be good in large laboratories (which are prepared for large productions) to divide the laboratory into two parts, one for showing films and the other for printing and enlarging operations due to the different safety light suitable for each of the two purposes, so they are separated by barriers that make the entry and exit corridor in the shape of the letter U, or according to any of the following: The designs shown in figures (114-118) are all designs that ensure that light does not pass through if a person enters or exits from one section to the other, and without his entry or exit disrupting the work.

In preparing such partitions separating the different departments, one must note the mechanism (especially if its purpose is to establish an entrance separating the laboratory from the lighted outer room).

(a) The space occupied by these entrances should not exceed the appropriate limit, otherwise we will surely lose spaces that could have been used in any of the two rooms.

(b) The interior walls of these partitions shall be painted with matte black paint.

(h) To be designed in a way that reduces light reflections as much as possible and prevents them from reaching the inside of the laboratory (Fig. 116).

Also, work must be done to prevent the penetration of light through the windows of the dark room, and we show in (Fig. 119,120) some of the methods that can be followed to achieve this purpose.