Lighting Installation - Basic vocational knowledge (Institut für Berufliche Entwicklung, 164 p.) 10. Mounting of Lighting Installations (introduction...) 10.1. Mounting of Indoor-Lighting Installations 10.2. Factory Lighting - an Example of Indoor-Lighting Installations (introduction...) 10.2.1. Metal Working Factories 10.2.2. Textile Mills 10.2.3. Agriculture 10.2.4. Summary Hints for Practice 10.3. Outdoor Lighting Installations Demonstrated by the Example of Industrial Building (introduction...) 10.3.1. Criteria for Quality Assessment of Outdoor Lighting Installations 10.3.2. Production Areas 10.3.3. Storage Areas 10.3.4. Building Site Lighting 10.3.5. Summary Hints for Practice

Lighting Installation - Basic vocational knowledge (Institut für Berufliche Entwicklung, 164 p.)

10. Mounting of Lighting Installations

Lighting installations are to be found in a variety of buildings constructed by classic or modern methods.

Consequently, the arrangement, fixing and electrical feeding of the lighting fittings must be carried out accordingly. The techniques and technology applied depends on the material and know-how available such as working means and manufacturing means.

In addition, the purpose of the lighting installation imposes further decisions and/or limitation. The normal procedure includes the wishes of the future user, the examination of the network conditions, environmental and local conditions and then the projecting of the lighting installation with simultaneous ordering of the required materials.

Only then the practitioner starts to act. He is responsible for the skillful mounting of the lighting installation true to plan. The variety of regulations and standards to be observed go down to clearly outlined sections. Lighting installations are categorized by the following order:

Indoor Lighting

- Local lighting (working places)
- General lighting
- Emergency lighting
- Factory lighting
- Domestic lighting
- Lighting of social buildings
- Lighting in agricultural buildings
- Lighting of rooms for special purposes

Outdoor lighting

- Industrial buildings
- Filling stations
- Advertising installations
- Athletic grounds
- Streets, ways, squares
- Building sites
- Camping sites
- Port and quay installations

In the framework of this chapter only a limited selection of the relevant problems is dealt with.

10.1. Mounting of Indoor-Lighting Installations

In this context, a number of installation variant come into question. In the phase of projecting of an installation it must be decided how a useful, economical and effective solution can be achieved. The conditions of use of an installation are determined by the physical, chemical, climatic, technological and aesthetical demands on the lighting installations caused by the building itself and its environment.

The following points have to be decided upon:

- Only series-manufactured installation elements and systems are used.

- The elements or components of the installation systems shall be arranged and fixed directly on the structure or on parts of it without greater auxiliary constructions.

- The mounting elements shall be universally usable to the largest possible extent.

- As regards the fastening points, the permissible static loading of the truss or ceiling construction has to be considered.

- With metallic mounting elements, corrosion protection must be provided for; a connection of Al and Fe has to be avoided.

- In buildings with cranes or conveying equipment, horizontal or vertical installations are permissible only in definite places.

- Installations of any kind must not reduce the aesthetical quality of the general view of the respective building.

- The entire installation has to be considered as a complex system; it shall form a unity, starting from the arrangement of the distribution system over the horizontal or vertical circuits to the lighting installation as well as in connection with the balancing system and the controlling mechanisms.

For fastening the lighting fittings and for the run of the installation in the truss area, installation systems have been developed enabling quick and flexible electrotechnical equipment of a building. Table 35 informs about the preferred installation systems for the construction of lighting installations.

Table 35. Preferred indoor lighting installation system

Installation system	Application
High-current distributor	Rising main, main circuits
Rail channel systems	Rising main, main circuits feed line to luminous rows
Underground systems	Feed line to distributions, line from distributions to supports and walls
Baseboard and wallboard channel systems	Feed lines from distribution, to lighting fittings or switches, used in housing and social construction
Lamp brackets combined with installation carrier rail	Used mainly in social construction
Universal carrier rail system	Especially suitable for carrying and mounting the lighting installation and wiring in factory buildings due to great carrying capacity and fixing distance (truss level)

Universal carrier rail systems and the installations rails which are connected with the lamp bracket are of special importance. The technical advantages of the universal carrier rail systems are that the parts of the system can be easily combined, that wires can be laid independently, that the general view and protection quality are better, that re-installation or additional installations can be made in a cost-saving way, that the assembly and the change of connection points are easy. The components of the universal carrier rail system enable the construction of any kind of net in the ceiling or truss area for fixing installation wires, devices and lighting fittings.

Figure 57. Carrier rails for fittings in row installation

Another possibility of rational assembly consists in the use of installation carrier rails in connection with combinatory lighting fittings.

As far as the fixing of the lighting fittings, luminous rows or luminaire rows is concerned.

- fixing on carrier systems and
- individual fixing

are distinguished.

Individual fixing mechanisms are hooks, straps and ropes. When fixing a lighting fitting make sure that the suspension attachment can carry the 5-fold weight of the fittings, but at least 10 kg without being deformed.

In addition, the ceiling hook must resist a torque of 2.5 Nm for 1 minute. Ceiling dowel pins must be from hardwood, because those consisting of soft wood or plastic have too much shrinkage.

For extremely heavy lighting fittings, concrete fixing or fixing with the help of through bolts is to be preferred. With span-wire installations, maximum values apply as to the structure loading resulting therefrom.

Lighting fittings have to be fixed and arranged in such way that the accumulation of heat is avoided. Make sure that there is no contact with easily inflammable materials such as curtains, strawplaiting etc.

Lighting fittings must be fixed and arranged in such way that neither the operating temperatures nor temperatures occurring in the case of overload endanger the installation itself or the environment.

The fixing of lighting fittings immediately on the ceiling is allowed only if the ceiling consists of non-inflammable material.

By such material are meant: sand, gypsum plaster, stone, mortar, concrete, glass, asbestos cement, mineral wool and metal. On inflammable materials lighting fittings are allowed to be fixed immediately on the ceiling only if these fittings consist of materials which hardly catch fire. All the rest of lighting fittings must have a structure distance of 35 mm and must be closed on their upper side. If a lighting fitting has no top cover, it can be closed by a sheet metal of 3 mm in thickness. If inserted ceilings are constructed of easily inflammable material, even hardly inflammable lighting fittings must have a distance from the ceiling of at least 35 mm. The electric connection of lighting fittings must be realized only through fixed built-in terminals or luminaire terminals. As far as the terminals are suited to receive two or more cable cores, through-wiring or a branch is possible. If a through-wiring of lighting fittings in band arrangement is made, the internal temperature is decisive. The required reduction of the current-carrying capacity of the installation material is to be seen from the relevant standards.

Lighting fittings have to be included into the protective measures against shock even if they are not within hand reach. The following protective measures against hazardous contact voltage are applied to indoor lighting installations:

- Connection to neutral
- Protective lead system
- Protective insulation
- Protection low voltage
- Protective isolation.

With the protective measure of connection to neutral, which is used with the most installations, and with the protective lead system all conductive parts of the casing of the lighting fitting that can get alive in case of failure must be well connected with one another and with the protective conductor. Construction components of the lighting fitting must not be used as protective conductors. An exception are installation carrier rail systems, which may be used as protective conductor supposed that their structure allows it.

Especially strict conditions apply to protective measures in rooms used for medical purposes such as the maintenance, monitoring and restauration of vital functions of patients. These purposes include functional unities such as operation, functional diagnostics, endoscopy, childbirth, premature infants, emergency cases, diagnostic radialogy. In such rooms even those lighting fittings which do not serve for general illumination must be provided with the protective measure of the protective lead system with constant control of the insulation resistance of the active conductors to earth.

With lighting fittings with protective insulation, no connecting of a protective conductor - neither directly nor indirectly - must be possible!

The protective measures of protective low voltage and protective isolation are applied to hand lighting fittings for use in boilers, silos, bakery ovens, etc. Permitted wiring materials for lighting fittings are:

- holder wires type H05V-V and
- flexible cords type NYPLYw.

Fixed connecting leads must have a minimum cross section of 0.75 mm².

The following cable material has to be used:

- NYFAw	for	55 to 105 centigrade
- N4GA		up to 120 centigrade and
- H05SJ-K		up to 180 centigrade.

There must be no risk of the cables being damaged by lighting fitting motion.

Mobile lighting fittings may be supplied with current by plug and socket connections or in a fixed way, but tension-relieved, over an appliance coupler.

Lighting fittings permitted to be operated in temperature ranges other than 30 degrees centigrade must be specially marked, for instance ‘T45gradC’ or ‘for outdoor lighting only’.

The hammer symbol stands for rough work such as heavy industry, building firms, agriculture and so on.

If the following symbols are to be found on a lighting fitting, this means: 60 W T 30 °C

Lighting fitting for rough work; water and dustproof; protective insulation; maximum wattage 60 watt; usable in temperature up to 30 degrees centigrade.

Fittings to be built in furniture must be marked for this purpose. Furniture fittings for filament lamps are marked as follows:

The same applies to furniture fittings with discharge lamps, if the inflammability of the respective piece of furniture is not known.

Lighting fittings bearing a furniture mark may be fitted on materials of normal or little inflammability.

In rooms with bath-tub or shower lighting fittings are allowed to be fixed in zone 2, if they have a protective insulation and at least the protective system of IPX4. They must be connected by plastic cables - no metal sheathing! In rooms with swimming-pool, lighting fittings should be placed at a distance of 2 m from the rim of the basin and in any case out of hand reach.

Underwater lighting fittings must resist hydrostatic pressure, this is to say they must be enclosed in a IP68 watertight capsule and operated with protective low voltage (25 V). There are three types of swimming-pool lighting fittings:

- Connection to the net and replacement of lamps is made from the side opposite to the water.

- Replacement of lamps from the front side after draining.

- The complete lighting fitting is taken out for replacement of the lamp.

Lighting of saunas must be switched separately. In the terminal boxes, breaking terminals must be built in that with the outgoing circuits the insulation test can be carried out without disconnecting ‘N’.

10.2. Factory Lighting - an Example of Indoor-Lighting Installations

This partial field comprises the following focal points:

- Metal-processing factories
- Chemical works
- Textile works
- Enterprises of electrical engineering and electronics
- Pulp, paper and printing works
- Energy supply plants
- Agricultural units
- Mining works.

On the basis of a number of the above mentioned focal points problems in connection with special lighting installations shall be discussed.

10.2.1. Metal Working Factories

The technological working process in metal-processing factories is determined by the final product. This means that there are no individual separate workshops for every single step of manufacturing but the workpieces are processed or worked by various machines arranged in succession in the same large room. This transition to flow-line production requires - as to lighting engineering - that the illumination in such room is determined by the work to be done most frequently. In general, illumination for these conditions is 500 lx.

Visual tasks requiring greater illumination should be supplied with light by workshop place-orientated general lighting or by local lamps.

In heavy industry halls fluorescent lamps or high-pressure discharge lamps are used according to the height of the hall and the demands made on colour rendition. Halls of more than 6 m in height are illuminated by downlighters or broad-beam spotlights equippes with high-pressure mercury vapour lamps.

A special branch of industry within the metal-working sector are the foundries. The lighting problems to be solved here are mostly due to the dark working material such as moulding sand, cast members, black iron, etc. In addition, the room limiting surfaces are exposed to much dust and soil, so that the reflection conditions on walls and ceiling are poor. The visual task in this field of production consists in the recognition of the negative model contours in the moulds.

A useful illumination of these industrial rooms can be supplied by a general lighting in connection with downlighters the illuminations being between 150 and 200 lx.

The illumination of such rooms shall provide a good local evenness in order to reduce the risk of accidents.

Additional local lamps are required where certain operations at work benches or the manufacture of complicated cores need a better lighting level.

In foundries and similar works high-pressure mercury vapour lamps with clear glass bulbs and high-pressure sodium vapour lamps have proved good. The advantages of this kind of lighting consist, above all, in an increase in visual acuity by intensified contrasts.

Similar conditions are to be found in smelting plants, rolling mills and others. Especially in rolling mills monochromatic light is used for examining the rolling material as to its surface quality and for crack detection.

In factory halls of the metal-working industry, where large machines such as presses and shearing machines are installed, the illumination is so much reduced by the shadows thrown by the machines, that in addition to the general lighting local lamps are required for each workshop place. The best solution of this problem is a local lamp built in the machine by the manufacturer of the machine.

Particularly complicated is the planning of lighting installations in motorcar industry. The extensive technological equipment in the form of overhead transportation means, spot-welding units and other technological facilities require close cooperation of lighting engineer and technologist for the planning of the lighting installations.

Often, in this branch of industry, a satisfactory illumination of the workshop place can be achieved only, if workshop place orientated lighting fittings or local lamps are installed.

In many metal-working factories, spray-painting units are necessary. With the lighting of spraying cabins and fully automatic spraying plants in varnishing units each workshop place must be sufficiently and very evenly illuminated according to the respective material to be spray-painted.

10.2.2. Textile Mills

Textile industry is divided into two major branches: mills that produce the thread and those processing the thread.

In the thread-producing mills, i.e. in spinning mills and finishing mills such as twisted-yarn mills and dye-works, most of the lighting tasks are solved by a general lighting or by workshop-orientated lighting. Many modern factories are accommodated in windowless buildings, because the processing of synthetic fibres makes high demands on constant climatic conditions. Therefore, often combined solutions are to be found in these factories, which unite air-conditioning and illumination by using climatic lighting fittings. If the lighting fittings cannot be integrated in the inserted ceilings, it must be considered that in cotton processing mills much dust deposits on the fittings due to fibre flight and that static electrification may easily lead to explosion and fire. For this reason, special lighting fittings for textile mills or dustproof fittings with a reflector opening angle of 60 degrees are used.

The illumination level in the thread-producing and thread-finishing mills is determined by the size of the visual object and the colour of the material to be processed (light or dark). For thread control a workshop place-orientated lighting is the best suitable one.

For colour pattern making in dye-houses special cabins for this purpose are required. Self-contained cabins must be constructed in order to avoid falsification by other light sources.

The illumination level of general lighting in textile mills ranges between 500 and 2000 lx according to the respective colour of material and contrast conditions. Special fabric control which need good contrast effect with a high level of illumination - e.g. for the detection of torn threads or knots that may occur in a piece of material - requires special local lighting. For fabric examination long tables are used on which even very long webs of cloth can be laid out.

The illuminations required for the inspection tables vary between 500 and 2000 lx according to the degree of reflection of the material. The fittings are suspended approximately 1 m above the upper edge of the inclined tables. The incident light provides enough shadows and highlights on the fabric to enable safe detection of possible faults.

10.2.3. Agriculture

Also in agriculture, there is an increasing demand for good illumination. For lighting stables, cowsheds and others mainly directly radiating lighting fittings are used. For rooms painted in white colour or whitewashed medium illuminations of 100 lx are sufficient. In cowsheds of a width up to 6 m the lighting fittings can be placed over the manure way. In cowsheds of several rows about one third of the required lighting fittings are installed above the fodder way. The fittings in the fodder way must be protected against mechanical damaging so that no glass splinters can fall into the fodder.

Milk-processing rooms must be absolutely clean. Since all work in this field is to be done early in the morning or in the evening, there is a permanent need for artificial lighting. Here too, the average lighting level is around 100 lx. In the milking parlours an underground lighting is recommendable.

In piggeries the right lighting of the troughs is of special importance in addition to the general illumination of the pigpen.

The recommended illumination for this purpose is approximately 50 lx. In pig sties for brood-pigs the average illumination should be 100 lx. The best place for the lighting fittings is above the middle of the brood stall so that there is sufficient light for assistance and care with littering.

In hen-houses illumination has to fulfill two tasks. On one hand the hen-houses shall be lighted, on the other hand the hens shall be stimulated to lay more eggs. Nearly all houses in intensive poultry farming are nowadays designed as dark space, no matter if the poultry is kept on the floor, in large numbers or in cages. For these hen-houses detailed lighting schedules have been developed which normally provide for an illumination period of 14 hours. Only in exceptional cases it is allowed to prolong this lighting time, for instance if the time of moulting shall be shortened or if young hens shall be stimulated to lay eggs as early as possible. For intensive poultry farming illuminations of 50 lx are sufficient. The light colour should be within the range of 3000 K.

Very good successes were made with the help of the light colour ‘warm white’ with fluorescent lamps.

In storage rooms, potatoe sheds and other agricultural space an illumination of 50 lx is sufficient. Special attention has to be paid to the lighting of stairs, ladders and hatchways for throwing down goods or materials, because bad sight conditions are especially dangerous in these places.

10.2.4. Summary Hints for Practice

To the above mentioned focal points made in the field of ‘industrial lighting’ the respective standards and regulations apply to the installation. That means that - irrespective of the mere task of illuminating - the installation of the lighting fittings, cables, leads and accessories now as before is subject to the valid standards concerning the protection and functioning of the entire installation.

10.3. Outdoor Lighting Installations Demonstrated by the Example of Industrial Building

Lighting installations in industrial building comprise the following focal points:

- Production areas
- Storage places
- Inspection lighting as to order and safety
- Outdoor switching stations
- Illumination of railway trackages
- Illumination of building sites

In this paragraph too, it shall be pointed to the problems in connection with special lighting installations on the bases of some of the above mentioned focal points.

It is the task of outdoor lighting installations to create the appropriate visual conditions for working processes such as occur in production, merchandise traffic and traffic in the dark. Also the lighting shall increase the safety of workers and users of the traffic facilities. The best visual conditions for working in the open air are provided by natural light. There are limits to artificial lighting for economical and energy reasons, so that outdoor lighting installations provide visual conditions equal to those of lower daylight level by which the visual qualities of the eye are affected. Favourable lighting conditions in the open can only be achieved if and when combined lighting in the form of a system of general lighting and local lighting is applied.

It is not always possible to take all important aspects into consideration when planning an outdoor lighting installation.

Outdoor lighting installations are projected on the basis of nominal illuminations and requirements of evenness. However, the quality characteristics of glare limitation, contrast conditions, light direction and shading have to be observed. The most frequently used lamps in outdoor lighting installations are high-pressure mercury vapour lamps, metal vapour lamps and high-pressure sodium vapour lamps.

With outdoor lighting installations two lighting systems are distinguished:

- Decentral arrangement of the fittings, for example single lighting fittings on lamp poles, and

- central arrangement of the fittings, for example floodlighting towers.

Decentrally arranged lighting fittings are used for illuminating works streets and industrial open-air surfaces. For the latter on condition that technology and geometrical structure allow this solution.

Works road or streets are different from normal roads in so far as they are situated within an enclosed area. They are not open to the public. Sometimes, works roads are directly connected with working places, e.g. unloading stations. The illumination level for works roads is determined by the traffic density to be expected and the paving.

With the illumination of industrial open-air areas by decentrally arranged lighting fittings, place and height of light point of the fittings should be chosen in such way that with view to the visual task the most important quality criteria are observed.

According to the respective geometrical conditions and the possibilities of arranging the lighting fittings, following types of lighting fittings are used:

- Fittings mounted on top of lamp poles
- Lighting fittings with rotational symmetrical light distribution
- Lighting fittings with two planes of symmetrical light distribution
- Lighting fittings with one plane of symmetrical light distribution.

The illumination of decentrally arranged lighting fittings can be calculated with sufficient accuracy by the efficiency method. The central lighting system in the form of floodlighting towers has the following advantages:

- Little number of poles

- Possibilities of rapid adaptation of lighting to changed technology by changing the direction of the floodlighting

- Easy maintenance.

The disadvantages of such installations are:

- Little vertical illumination
- Risk of cast shadows due to one-sided light direction
- Higher costs in comparison with decentral lighting systems.

The tower position with floodlighting installations is determined mainly by the territorial conditions and the purpose of use of the area to be illuminated. The number of towers depends on the size of the surface to be illuminated, on the type of floodlight and on the lamp power. With the arrangement of the lighting fittings on the tower and the decision on the height of the tower, special attention has to be paid to the following factors:

- Adherence to the glare protection angle
- Avoidance of irritating cast shadows
- Guarantee of even illumination
- Observance of the maximum floodlight equipment per tower.

For economical reasons, the towers should be placed, if possible, within the area to be illuminated - equipment of the fitting platform on four sides. If, for technological reasons, the tower cannot be put in a central place - for instance with the illumination of a container store frequented by a gantry crane, the towers should be placed as closely as possible to the surface to be illuminated.

When deciding about the place for the floodlighting tower, the conditions of assembly and erecting must also be considered in addition to lighting task. The tower is preferably assembled on the floor or ground and erected with the help of the appropriate erecting and pulling equipment. Consequently, there must be a driving way for the pulling machine. Lamp towers can also be erected by mounting the individual parts of the pole on with the help of a crane.

During the planning phase of the floodlighting installation it should be found out if buildings or other structures are perhaps suitable for bearing the floodlights.

10.3.1. Criteria for Quality Assessment of Outdoor Lighting Installations

- Nominal illumination - these are fixed by standards.

- Shadowyness - formation of cast shadows has to be avoided.

- Local evenness - avoidance of greater differences in luminance within the field of view.

- Glare limitation - avoidance of direct exposure of the eye to the light source.

10.3.2. Production Areas

There is a trend in heavy and chemical industry to shift technological processes from indoor to outdoor space. This leads to new requirements on lighting. The general illumination in production areas shall be at least between 30 and 50 lx. The nominal illumination at the workshop or working place is determined by the visual task and is assessed by the described method.

Hazardous points of the technological plant should be pointed to by increased illumination, spotlighting or use of different light colours.

For general lighting, central as well as decentral lighting systems are used central lighting being preferred with large plants.

Local lighting fittings can be stationary or - if they are used only for repair work - mobile. The mobile ones are movable lighting towers, lighting platforms or lighting poles with heights of light point between 6 and 20 m. Stationary working place lighting fittings are fixed on available structures or auxiliary structures. If a combined lighting system is used, the transfer from the illumination of the environment to that of the working place should be made as soft as possible.

This means that the working place lighting fittings must be installed at a greater distance from the place of working than the local lamps at machines and workshop places in indoor rooms.

Between the working area and its environment the evenness of lighting should not exceed the ratio of 5:1.

With growing distance from the working place, the illumination may subside to the given values of general lighting. The lighting fittings are chosen according to the purpose of use, mechanical stress, required protective system and aspects of maintenance. As to protection against moisture, outdoor installations must be provided at least with the protective system IPX3. The lighting fittings shall comply with degree of protection I - with protective conductor connection - or with degree of protection II - with protective insulation.

10.3.3. Storage Areas

Storage areas are divided into three types:

- Those with permanent handling during the night
- Those with temporary handling of material at night-time
- Those with occasional handling at night.

Other storage areas where no activities take place during the night are equipped with a control or survey lighting.

With increased requirements on the visual tasks on storage areas or with increased risk of accident, the illumination is intensified by one step, respectively.

The given values of illumination do not only refer to the places where loading and transportation work is done but to the entire storage area. Endeavours should be made to install an additional local lighting immediately on the working zones. For instance, an additional local lighting can be realized by fixing floodlights to the supports of gantry or bridge cranes thus creating a light direction transverse to the direction of motion. Further additional lighting fittings can be fixed also on the crane bridges in order to supply the crane driver with sufficient local lighting. However, these lamp sockets should be provided with a spring-loaded suspension device to absorb the permanent shocks caused by the crane.

With railway goods wagon and container unloading by crane, further additional lighting fittings are required for lighting up shadow zones due to laterally incident light. The problem could be solved by erecting one lighting pole at each crane track, so that the light of the floodlights installed here can fall between the wagon rows. (Pay attention to glare limitation.).

General lighting of storage areas can be realized as central or decentral installation, the trend going to a central arrangement of the lighting fittings for large areas, though.

10.3.4. Building Site Lighting

Also in building industry shift-work is more and more prevailing.

As the most significant differences between the working conditions by day and at night the different conditions of lighting must be considered.

The equal requirements on the quality of work by day and night result in certain minimum requirements of the lighting. The designer of lighting installations for building sites has to consider the expenditures that would be necessary to erect the installation and the requirements of the work to be done on the building site as well as safety aspects, protection of health and technical reliability.

In planning lighting installations for building sites the most important quality characteristics have to be observed as it is done with other kinds of lighting installations: sufficient level of illumination, sufficient glare limitation, sufficient shadowness and local and temporal evenness.

Standard values for the illumination of building sites are given in Table 36.

Table 36. Service illuminances and uniformity requirements on general and local lighting at building sites

Visual object, operation	General lighting		Combined lighting
			Local lighting	Portion of general lighting
		(Illuminances indicated in lx)
Operations with which the majority of the visual objects is up to 2.5 mm big	100	1:3	<= 500	15
Operations with which the majority of the visual objects is between 2.5 and l0 mm	50	1:5	200	10
Operations with which the majority of the visual objects is between 10 and 25 mm as well as traffic ways within buildings	25	1:5	100	5
Storage areas and handling installations with temporal handling work, temporal stacking work (1)	10	1:5	50	5
Survey lighting	5	1:8	-	-
Inspection lighting without special requirements, only if necessity arises	2	-	-	-

(1) With increased risk of accident, the previous illuminance is applied.

10.3.5. Summary Hints for Practice

As stated under point 10.2.4., the regulations and standards issued by the legislator apply to each respective installation according to the local conditions. In addition to these, regulations for overhead constructions - floodlight towers - have to be observed.

Questions for repetition and knowledge tests

1. What conditions are known in connection with installing a lighting installation?

2. What must be paid special attention to when arranging lighting fittings?

3. How can - despite all difficulties - a good illumination of the working areas be achieved in metal-working industry?

4. In textile industry, orientation to brightness alone is not enough. For what reason?