Dark Room Day Light Processing and Film Faults Lalit K. Gupta Department of. Radio-diagnosis & Imaging PGIMER, Chandigarh

Construction and lay out of dark room Types of processing Films Fault

Dark Room The Dark inside the room so far is called dark no leakage of white light.

Dark room Planning. These are following points to be take care before planning the dark room : Consideration Construction Location Illumination Equipment’s and lay out

Consideration The following persons to be involved before planning : Radiologists Radiological Technologist Architect Engineer from the Civil and Electrical side.

Construction Before start the construction we must first look which type of processing unit are required :- Manual Processing Automatic Processing

For the healthy environment in the dark room these point should be taken under consideration before construction :- The Size of dark room, Walls, Roof, Floor, Types Entrance, Ventilation, Water and electricity, Radiation protection of the dark room

Ideal size of the dark room Should not be less then 100 Sq. feet for the manual processor less space is required for the automatic processor. Ceiling Should not less be then 2.7 Mt in height

Floor material Walls :- Should be such that Non porous Resistant to staining by chemicals or other liquid. It does not be come slippery when wet. Walls :- should be given the adequate protection from the chemicals till the height 1.3mt for that the ceramic tiles applied to adjacent of wall surfaces.

Radiation protection Ventilation Should 2mm lead equivalent materials are required or 9inch thick brick wall 3 inch cement plaster on each side or 1 inch thick Ba plaster on each side. Ventilation Need good ventilation because the dark room staff is unrealistic to expose with chemicals. Air conditioners are the good efficient cross ventilator then the fans for maintain the temp.

Temprature and Humidity Temp. Of dark should be between 18-20degree cent. Humidity should be ideally 40-60 %. The type of entrance in the dark Double door system as we have already in the dept. needs the less space.

Location of Dark Room The dark room should be situated as near as possible to the radiographic room, or placed between the two radiographic rooms. The wall of dark room should be a common with the radiographic room. Ideally, it should be centrally located

Safe Light The term safe to some extent is misleading in so far as it is not absolute it implies the degree of safety. We can say its response is related predominantly to wavelength or color, but also significant the intensity of light. In a general radiographic darkroom there is no necessity to work in a red light. It is depend upon the sensitivity of the film .

Direct safe light The lamp has circular filter 14cm in diameter with 15 watts bulb inside and colored filter placed in front of bulb, it may hanging on wall above the dry bench and the processing unit or other working point.

It should be placed such that the sensitive material is normally handled no near it to then 4 ft and also it should be the situated the same distance on other working place in the dark room. The use of any direct illumination is not recommended for fast orthochromatic or panchromatic films.

Equipment’s and lay out A well planned dark room should have the following characteristics:- Effective separation of wet and dry benches if both occurs in the same room. Orderly layout of the equipment in adequate space Clear traffic lanes so that the staff working in the dark room are not strike each other.

It has two working bench Dry bench Wet bench

Dry Bench or loading Bench A long table with hard wood and teak should be used for placed to / loading/unloading cassettes. At least 2.5 Mt in length and 600 mm width and height should not be less then 900mm and minimum 75mm space are required for toe.

The some other accessories are also required in the dark room are as follows Hooper for storage of films The cassettes racks are required to keep the cassettes. Interlocking pass box is required to transport the exposed and unexposed films /cassettes from dark room to radiography room and vice versa. Films Hangers. Film drier for to dry the films.

Wet bench Processing unit for manual operation In order to avoid these difficulties the routine processing of radiograph is under taken with equipment of which the basic components are a number of deep tanks.

The Manual processor consists of a large master tank which includes certain smaller tanks and divisions. From Left to right in the drawing These are as follows lidded tank for the developer A tank or compartment, usually having a separately tapped cold water supply, which provides a mean to rinse films between developing and fixing solution. A tank for fixer.

Mannual film Processing unit

Tank capacities The individual capacities of solution tanks in a process vary from model to model . Typical specifications are given below: - The dimension of soln. tank for 50-60 films need 5- gallon each for developer and fixer is 1420 mm long x 690mm deep.

Automatic processor Improvement in the film processing. The purpose of automatic processor is used to : Improvement in the film processing. Efficiency and stability of Image quality.

System components These are following components of automatic film processor:- Feed tray Rollers with different assembly: 1. Entrance 2. Deep racks 3. Turn around 4. Cross over 5. Squeegee 6 Dryer. Receiving Bin

Mechanism of automatic processor Dry to Dry films. Transportation of film from one tank to another. To keep the film for a set period of time in Developer, Fixer, Water, and Drier. Automatic process the solutions are always agitated and getting regular and automatic replenishment.

How we get the processed from dry to dry film quickly The following principal on which Developing and fixing is quick: Higher temperature and shorter time. The temp. Developer is 30-34 degree cent and processing time is app. 25 sec. Circulation of solution. Moment of film. Getting regular replenishes. Chemical highly activated. Emulsion is also thinner and base material is also thinner.

For Fixer Fixing Time is 15-20 Sec Squeezing rollers are in between the developing tank and the fixing tank to stop the action of developer and reduction in swelling of gelatin. Well Buffer fixing chemicals. Circulation of replenishes Moment of film

Washing Washing time is 15 sec –20 sec . Water is always agitated. Moment of film. One Film wash at one time.

Drying Time is 15-20 sec The water should be squeezes out of the film with the squeezes for adequate drying from the water tank Moment of film Reduction of humidity by controlling blower or by dehumidify .

Advantages of automatic processor Radiographic Deptt. Patients Hospital

Radiography Advantages Standardization of exposure factor. Standardization of processing. Good density and contrast on the films which means the quality of films will improve. Less artifacts.

Advantages to the Deptt Small space is required for automatic processor. Elimination of accessories of dark room such as hangers, clips, Drier. Wet bench. Allow quick viewing and reporting of the film. Advantages to the patient Less waiting time Quick Diagnosis of Diseases

Advantages to the hospital No large waiting hall is required Saving of staff such as dark room asstt. And dark room tech. Silver recovery is efficient.

Day Light film processor A technical development which has changed the ways in which work may be done in the x-ray dept. in the introduction of what known as system for day light handling of x-ray films.

The term day light film handling means that the film goes from exposure in the x-ray room to its viewing as a finished radiograph in the reporting room, it does not need to progress through dark room at any stage. These equipment can be installed anywhere under any ordinary artificial light, no safe light is needed. So these method might be called day light film handling system.

Day Light Automatic film Processer

Day Light using cassettes Day light system which handle cassettes perform a series of operation for which the following items of equipment are necessary :- A cassettes a which in normal room lighting can be automatically loaded before radiographic exposure, unloaded after wards and then reloaded with film in readiness for the next exposure.

Day light system without Cassettes Or Cassette less system:- Day light system for automatically handling x-ray films without putting them into cassette are in use especially for the radiography of chest or digital imaging radiography.

Day Light system without cassette odelca camera

Loading , unloading a film magazine and Processing in Dark Room

Loading of films in day light and Processing in Dark Room

Day Light Loading and processing in day light

Day Light Loading and film processing in day light system Dry View Camera

Advantages of day light film system The staff who work alone in the x-ray dept. are able to remain in contact with their ill and injured patients. Away from the safe light in order to process the films and to reloads the cassettes. There is no need to coop in the dark room, working conditions are improved, time is saved, and skilled staff is more efficiently used. X-ray rooms do not need to close to the dark room and so there is greater scope in departmental planning. Also day light film processor needs less space as compared the dark room automatic process. Automated handling reduces the risk of damage to films and intensifying screens.

DARKROOMS- STILL NECESSARY Darkrooms are still necessary for manual processor and automatic film processor. Its concern with the loading automatic film processor magazine. Necessary for conducting certain quality control test ( eg Sensitometeric test)

Radiographic Films Artifacts

Films artifacts are broadly divided into three catagories: A. Artifacts due to storage and handling B. Artifacts due to processing faults C. Artifacts due to error in exposure.

A.Image artifacts due to storage and handling:- These artifacts includes such as :- Fog Static marks Intensifying screens and cassette Storage and handling films in the dark room both exposed as well as unexposed.

(a) Causes of Fog:- Due to storage period and storage conditions:- The increase in fog depends not only on the length of storage but also storage conditions temperature humidity of air chemical fumes in the place where the films are stored.

If the temp. exceed 40oC it greatly effects the quality of film by producing a fog and even may cause sticking. In general x-ray films should be stored at a temperature of not more that 20oC and the humidity around 50%. We should inspect the film storeroom and use the film near to the expiry date earlier than with longer expiry date. X-ray film packs must be placed in the storeroom in vertically position.

Fog Due to Storage and Handling ie expiry date film uniformly fog appears throughout on the film, one that appears with its density higher

(ii) Fog due to safe light:- The fog is produced by the safelight because:- The film was placed under the safelight for long period of time. The film was handled closer to the safe light. The wattage of the bulb used in the safelight exceeded the standard range. The kind of safe light was not suitable for the spectral sensitivity of the film.

The fog appears on the film when the hand was placed on the film and exposed by safe light as shown in fig fog appears in the form of uneven densities

(iii) Fog due to leakage radiation :- When unexpected shape of an article or a pattern of a fiber on film, appears in a radiographic image. We have to take care to store any film in the x-ray room. The x-ray cassette or storage box should be sealed with lead and magazine. It should be placed under protection so that it is not be effected by x-ray radiation.

leakage Radiation cont. These troubles may appear on a film when it was exposed to scattered radiation.

Fog due to expiry date Fog due to Safe light Fog due to scattered Radiation

(b) Static marks These are caused by the discharge energy of static electricity produced in the film and the branch like pattern images appeared on the film are called static marks.

(b) Static marks Dark marks appearing as branches like pattern on a processed x-ray film

These are some of causes A film sheet when drawn quickly from the interleaf of film box. While film was unloaded from the cassette with a force. Intensifying screen when used immediately after strongly wiping its surface with a dry cloth. When ever there is a strong friction between the film and the roller

(c) Due to Influence of pressure applied on the film:- While loading unexposed film into the cassette, it is partially bent. Due to the little pressure applied by the fingers on the film a white marks appear after development of the film. Heavy cloudy white artifacts

(d) Film Artifacts due to the Intensifying screens:- Dust on the screen Scratches on the protective layer or when phosphor is removed from the screen when it is used for a long period of time. White spot like artifacts on the film

(B) Artifacts due to processing faults: processor are not cleaned regularly then roller marks appear on the film as shown in fig Rollers marks appears on the film

(C) Artifacts due to error in Exposure, Malpositioning & Equipment fault :- Improper patient position Error in Exposure Mal positioning

Motion Artifacts:-

Double exposure :- It occurs when an image receptor is exposed more than once before the film is processed

Other film Artifacts :- External foreign bodies like embroidery

Grid Artifacts :- Grid lines appears as improper centering Grid cut off decrease optical density Proper use of Grid

Conclusion:- We must take adequate steps to avoid these image artifacts . It not only result into degradation of film image quality, but also increase the cost of the procedure, wastage of time, increase of work load on the equipment and unnecessary radiation to the patient as well as delay in the treatment time.

Thank you