Chameleon mask for welding: classification of light filters and choice of mask

Safety precautions

Before putting it on, check the settings, operating mode switches, and battery charge.
Always check to see if the filter is getting dark. If it turns off during welding, the protective glass protects the eye to a small extent from IR and UV rays. But it’s safer to stop working immediately. It is dangerous to use a faulty mask. If a defect is found or the filter does not respond, the malfunction is serious and welding cannot be continued. It must be remembered when working that the powerful radiation of the arc and molten electrodes is destructive. In addition to discomfort, this threatens to damage the retina. To prevent loss of vision, it is necessary to correctly adjust the degree of darkening of the filter.

Possible malfunctions and methods for eliminating them

1. The screen will not respond to light unless connected to a power supply. If the model is equipped with AAA alkaloid batteries or rechargeable batteries, charging indicators are displayed in the screen area. If the red light is on, it's time to replace the batteries. Solar panels are charged while welding. If the mask does not turn on, point it towards a light source for a few minutes.
2. If the screen darkens unevenly, check the distance from it to both eyes. Perhaps while they were adjusting the mask and adjusting it to the head, the filter shifted. It should be parallel to the face. Loosen the clamps and align the casing.
3. If the screen flickers during welding, it may be due to the outer glass. Sometimes it is enough to wash it. In case of mechanical damage (scratches, surface chips) it must be replaced. If the filter continues to act up, check the cleanliness of the sensor surface. When there are two operating modes (welding and grinding), check which position the switch is in. The screen may flicker when low-current welding in low sensitivity mode. The desired level can be established experimentally during operation.
4. The filter does not darken immediately in the cold. Viewing screens quickly change the degree of darkness in the temperature range from +50 to -10°C; Chameleons are not intended for harsh winters.
5. If the weld seam is difficult to see, there may be several reasons. Sometimes the film is forgotten on the protective glass. You can try cleaning it, switching the dimming control.

How to choose a Chameleon mask and how to check it when purchasing

A welder's mask is necessary for everyone who uses welding equipment.

From this article you will learn: how to choose a “Chameleon” welding helmet and how to test it without welding before purchasing, what to look for when choosing and much other useful information

Before purchasing a mask, you should carefully read its passport. Even a very simple mask with an automatic light filter (ASF) has a passport, which indicates its degree of darkness, recommendations for the type of welding (MIG, MAG, MMA, TIG) and the type of battery.

How to choose a welding mask? Read more about all the intricacies of choice further in our article.

Welding goggles chameleon

You should wear goggles during short-term welding, which does not require additional face protection. Modern chameleon welding glasses look more like a diving mask, protect your eyes perfectly and are, in fact, one large screen.

Due to its size, the viewing window has an excellent viewing angle; in good models it fits tightly on the face, preventing sparks from getting into the eyes. The glasses weigh about 300 grams, have an adjustable elastic band and come in different sizes. In other words, it is possible to choose exactly those in which it will be convenient to work.

Mask manufacturers

The bulk is produced in China or Korea, there are both completely unusable products and quite good samples.

For professional welding work, it is worth taking a closer look at European brands. In terms of pricing, they are, of course, more expensive than their Chinese-Korean counterparts, but by purchasing them, you will really get a high-quality mask. It is worth taking a closer look at these companies:

• OPTREL.
• SPEEDGLAS.
• FORTE.
• OTOS.
• PROTON.
• DNIEPER.

Well, of course, you can choose a high-quality mask from domestic manufacturers.

There are also often promotional offers of the following type: buy a welding inverter and receive a chameleon mask as a gift. As a rule, such shields are the cheapest and their origin is rather doubtful. Sometimes professional protection is comparable in cost to the price of a welding machine.

When choosing protective equipment for welding work, you need to set your priorities correctly. Yes, a high-quality mask is a must. But how necessary is it? If you need a shield for periodic repairs in a garage with small-scale welding work, then you can take a cheaper domestic model. For such moments, even a regular welding shield with constant darkness is suitable.

It’s another matter when a mask is needed for constant work, when welding operations are carried out in large volumes. Then the chameleon shield will become a necessary equipment.

Many professionals still make do with shields with regular permanently darkened filters and often recommend them as the best option. But here it’s more a matter of habit, because chameleons create more comfortable working conditions for the welder.

The question of whether you need to purchase a chameleon welding helmet and which one to choose depends on the work that will be carried out, taking into account personal preferences.

What do you think about chameleon masks and their use? If you have experience in their operation, as well as selection, share it in the comments block to our article. Point out the nuances that were missed in this article

What you should pay attention to and which samples are the best, taking into account your personal experience. After all, nothing can replace the advice of a knowledgeable person

Light filter for welding helmet

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A light filter is necessary to protect against ultraviolet and infrared radiation during welding. The automatic liquid crystal light filters found in Chameleon masks have many advantages over their simple analogues. The mask does not need to be constantly raised or lowered; thanks to the sensors, the light filter operates quickly and darkens when the arc is ignited, and after finishing the work it brightens. It's practical and safe.

Important!

The Chameleon welding helmet must be stored in a dark room or closet, at normal temperature (not hot or cold). Before use and after use, wipe it and the screen with a clean cloth so that they do not deteriorate.

The Chameleon light filter has a power supply, arc detection sensors, and control capabilities. It is quickly installed in the mask, can be powered by a solar panel or replaceable batteries (depending on the type) and can have 3 types of adjustment.

1. Adjustment of the degree of darkness. Placed on the outside of the mask or inside.
2. Adjusting sensitivity (how quickly the dimming is triggered).
3. Adjustment of the darkening period (long, short or medium).

Light filter for welding helmet Chameleon

Design and principle of operation of the mask

Basically, welding helmets are similar in design. They consist of the following elements:

• frame,
• neck protector,
• observation window. Protects against harmful production factors, makes it possible to examine the work performed,
• light filter - protects eyes from harmful radiation,
• solar battery photodetector (for “Chameleon”),
• filter dimming regulator,
• headrest adjustment strap clamps,
• external protective glass.

All welding shields must comply with GOST 12.4.035-78 and TU 3441-003-07515055-97, and also include a passport in accordance with GOST 2.601.

The mask is made from non-conductive raw materials. Domestic models are made of corrugated cardboard or rigid thermoplastic. Masks made from cardboard must be stored in dry places, otherwise they will simply become soggy from moisture. Imported ones are made mainly from soft, heat-resistant plastic and do not have this drawback.

The set with a welding helmet includes external protective glass (plexiglass, polycarbonate), which requires replacement when it gets dirty.

The welding shield is used as follows: when the welding arc is ignited, a special darkened glass is lowered, which does not transmit harmful radiation, and the body and outer glass protects from scale.

Operating the Welding Chameleon

The main requirement for caring for the mask: the light filter must be taken care of: it is easily scratched. Therefore, you cannot put the mask face down. It should only be wiped with a completely clean and soft cloth. If necessary, you can moisten the cloth with clean water. DO NOT wipe with alcohol or any solvents: the filter is covered with a protective film that dissolves in these liquids.

There is one more feature of any welding chameleons: they begin to “slow down” at low temperatures. That is, they operate with a delay, and in both directions - both for darkening and for brightening. This feature is very unpleasant, so you won’t be able to work normally in them in winter, even if the operating temperature is specified as -10°C, as on the TECMEN DF-715S 9-13 TM8. Already at -5° everything cannot darken in time. So in this regard, OTOS turned out to be more honest, indicating the starting operating temperature from -5°C.

Finally, watch the video on how to choose a chameleon mask for welding.

Carrying out maintenance

Welders should inspect the Chameleon at least once a month. Dirt is removed with a soft rag or cotton cloth. Cleaning products with aggressive, oily and abrasive bases are not suitable for glass. It is important to remember that filters are fragile and cannot withstand shock loads. To get to the light sensors, the casing is dismantled. This is done when the power supply is turned off, just remove the batteries.

Step-by-step instructions for replacing the protective screen:

1. The cartridge latches are moved to the center of the filter and opened.
2. The damaged glass is removed along with the rubber gasket, and it is replaced with a new light filter of the Chameleon mask.
3. The assembled cartridge is installed in its working position. It should fit tightly.

When replacing the filter, remove the regulator knob and potentiometer. Then the elements are assembled in the reverse order. Be sure to check the sensitivity lever; the delay time adjustment should work perfectly so as not to catch “bunnies”.

Marking of filters

The filter markings indicate the following characteristics:

1. Degree of darkness.
2. Optical glass type.
3. Light scattering indicator.
4. Uniformity of shading.
5. Angular dependence.

Darkness level

The main parameter by which glass is selected for certain jobs. Modern filters may use Russian or foreign markings, depending on the manufacturer. Domestic designations range from C1 to C13, but most often glasses with markers from C4 to C8 are used for welding masks.

European samples are marked from 7 to 16 DIN, although it is more likely to use filters with a rating from 8 to 14 DIN. The degree of shading is better for glasses with a larger number in the marking.

Solar panels, battery life

Some chameleon welding helmets are designed with a built-in, non-replaceable battery that is charged via a solar auxiliary panel. These helmets often require a charging period in direct sunlight before first use, and a similar charging period if they are stored for a long time, which can be a real problem when you want to start welding work as quickly as possible. The disadvantage of this type of mask is the fact that as soon as the battery wears out, the light filter does not work. It is better to buy a welding helmet in which the filter is powered by a replaceable battery and a solar panel, which allows you to start welding right away. Choose a filter with AAA batteries due to their low replacement cost and worldwide availability. Choose lithium batteries for longer life, but note that lithium batteries are more expensive than regular batteries. The service life of a regular AAA battery is about 2000 hours for MIG/MAG, MMA and other types of welding.

Possible faults

Regardless of the manufacturer and quality of the unit, any mask can break. The reasons for failure may be the following:

1. Violation of operating temperature conditions.
2. Mechanical damage.
3. Use of low-quality components.
4. End of natural lifespan.

If the operating rules are violated, first of all, they lead to malfunctions of the automatic light filter for the welding helmet. Before contacting official representatives, try to determine the cause of the problem. Some breakdowns can be easily fixed on your own, without the involvement of qualified specialists. Spare parts for repairs can be purchased at points of sale of welding equipment.

The simplicity of the mask design ensures no maintenance problems. A technologically complex device is more difficult to repair.

The mask can be powered either by a solar panel or by batteries. Battery failure is the main cause of chameleon problems. In this case, the solar cells may simply be discharged. To localize the cause, just leave the device under natural light and then check the functionality. Removable batteries need to be replaced. Replacing the power supply assembly will cost much more.

Problems with glass are visible to the naked eye - external defects in the structure will indicate this. In this case, the filter will not work properly. When replacing LCD glass, it is necessary to comply with the parameters of the element. This is the most expensive part of the assembly.

The biggest problems await the user in case of problems with the control board. In this case, independent repairs, without the involvement of service specialists, are impossible.

Which one to choose?

In order to buy a model for home and production, special attention should be paid to the following factors

Level of reliability of eye protection. Reflects the darkening parameters of the mask display, calculated in DIN and varies in the corridor from 3 to 15 units.

Additional options mode. After the metal hardens, the darkening should be removed, and the glass of the shield should become as transparent as possible. This allows you to continue the work process without removing PPE from your head. At the same time, the practicality and parameters of retinal protection directly depend on the speed of activation of the sensor. The optimal parameter is considered to be 0.1 s.

Ventilation. Welders are often forced to perform work in poorly ventilated areas, so it is best to choose “chameleon” PPE that provides the possibility of forced ventilation

This will allow workers to protect themselves from toxic fumes of hot metal and smoke generated when the electrodes burn.

The weight of the helmet plays an important role. When adjusted correctly, the headband of the product should not put too much pressure on the worker’s head.

At the same time, lightweight models made from synthetic materials are not able to protect the welder from accidental impacts resulting from falling objects.

Particular attention should be paid to the availability of all documents and certificates confirming the quality of the products. All data must be kept in the public domain and provided upon request

Consumers should be able to review the manufacturer's contact information and warranty terms. If at least one of these points is not met, then the safety of the helmet will be very difficult to confirm.

Obviously, the correct choice of any chameleon welding PPE implies increased safety. For the user, the main factor is to focus on the presence of a diagnostic option and the ability to display all information on the display, so that the worker can check all the design settings.

What a welder should remember

Adjustment of settings is carried out according to the attached instructions, and the performer must know:

• chameleon helmets are not suitable for plasma and gas welding;
• the product cannot be left on a newly welded structure;
• disassembling filter cartridges is prohibited;
• the product will not withstand strong impacts;
• Moisture is not allowed to get on the filter;
• solvents and detergents are not allowed when processing the mask;
• The batteries need to be changed only when the red light comes on, and the filter switches to grinding mode.

All types of adjustments are made before starting work.

Certificates for welding helmets

TR TS

makes a random selection of masks

When purchasing a chameleon mask for welding, be sure to require a TR CU certificate. What can you do if there is no certificate for your welding helmet? Just put it back on the display.

DIN

An employee of the DIN Certco accreditation center visits the plant and selects 16 welding filters from the batch. Selected filters are tested in accordance with the requirements of EN 379. If all selected filters pass the tests successfully, a DIN certificate is issued for one year. Devices for measuring all characteristics of the light filter must be available directly from the manufacturer. By the way, measuring devices are also subject to inspection.

After successfully passing the second test, the DIN certificate is valid for 4 years. After 4 years, repeated tests are done, and if successful, a certificate is again given for 4 years, and so on all subsequent times. DIN certification guarantees and confirms the safety of welding filters and a high level of quality.

DIN plus

DINPlus is valid for one year only

Since the first thing is the indispensable availability directly from the manufacturer of rather expensive equipment for testing automatic welding filters. Secondly, this is periodic quality testing by an independent certification center employee. What kind of filter quality can we even talk about when the manufacturer doesn’t even have quality control equipment? Just think about the kind of light filters he makes in his garage.

C.E.

according to regulation 89/686/EWG

Anticipating your question, what can prevent a careless manufacturer from providing one licked light filter for testing and then rivet the CE mark for life, we will answer, most likely, nothing really hinders. Therefore, all well-known manufacturers of welding filters go for more expensive voluntary periodic certification, since without an even more stringent DIN certificate, the sale of chameleon welding masks on the European market is almost impossible. Numerous accreditations and certificates are like awards for a soldier. If you have something to brag about, then why not.

A few more certificates

• ECS. The ECS designation confirms the product's compliance with all DIN requirements. Manufacturers who use such a mark, in contrast to the CE certificate, voluntarily subject themselves to constant checks of industrial quality control, measuring instruments, as well as final results, and always guarantee the high quality of the masks.
• CSA. Standards Association in Canada, standards and certification are the same as DIN. Manufacturing and manufactured goods are also controlled by annual audits.
• AS/NZS. Australian/New Zealand certificate, same as DIN accreditation. Once a manufacturer has received this accreditation, the Australian certification association SAIGlobal carries out an annual audit of the manufacturing plant.

Rules for choosing filters

Before purchasing masks or glasses, you should understand the optical characteristics of light filters and the specifics of using the products.

Recommendations for choosing filters for welding

• If you regularly carry out welding work, you should choose the “Chameleon” mask.
• The size of the filter determines visibility and comfort during welding activities.
• The filter response time can vary from 0.03 to 0.0001 s.
• You should choose models with continuously adjustable dimming levels, which are more comfortable than stepped ones.
• It is recommended to use universal filters that have a shade of 9-13 DIN.
• The optical class of the filter determines the clarity and visibility of the image through glass (the best option has an indicator of 1).

Additional features

Additionally, you need to pay attention to: dispersion, homogeneity and angular dependence of the filters, what type of welding will be used, current indicators, risk of mechanical stress

When choosing protective devices, it is important to decide how the work will be carried out: indoors or outdoors

When choosing protective devices, it is important to decide how the work will be carried out: indoors or outdoors. The type of work carried out is indicated by markings: E – electric welding, G – gas welding,

The type of work carried out is indicated by markings: E – electric welding, G – gas welding,

B – auxiliary work, C – marking for “Chameleon” type filters.

Marking of different types of welding

To ensure uninterrupted operation of the filter, you should pay attention to:

• an adjustment unit, which can be accessed on the front side of the mask, which allows for correction without stopping work;
• on/off system that increases the longevity of the power supply and filter;
• availability of changing power sources;
• the number of sensors that determine the response time;
• possibility of adjusting parameters.

When choosing a model, it is recommended to choose filters marked 1/1/1/2, which determines the relationship to the optical class, uniformity and light dispersion.

When purchasing, it is important to study the product certificate, warranty period, and location of service centers. Explanation of the symbols on the welding mask

Explanation of the symbols on the welding mask

Setting based on welding mode

Diagram of the front glass of the chameleon mask.

The customizable chameleon welder mask involves the use of several operating modes. There is no need to change filters - you just need to set the required mode. The modes are designated as follows:

• MMA – manual arc welding;
• MIG/MAG – semi-automatic arc industrial welding, designed to work in a gas environment of argon or carbon dioxide;
• MIG (light) – semi-automatic gas arc welding;
• TIG, GTAW - arc welding, for which a non-consumable electrode is used;
• SAW – semi-automatic welding using flux;
• PAC – plasma arc welding.

The instructions also include information about possible breakdowns. In addition to breakdowns, troubleshooting methods are indicated. In case of complex breakdowns, it is best to contact a service center, since the equipment can be damaged, and its further repair will be expensive. If the filter darkens unevenly, you must contact a service center. The filter is out of order, and you can’t fix it with your own hands.

If flickering is observed or there is no darkening of the viewing window, then you need to carefully clean the plate of dirt. If this measure does not help, then it is best to replace the plate, since it is damaged and changing the settings will not help. If the darkening is uneven, it is necessary to remove the mask and inspect the condition of the sensors

It is important to make sure that the surface of the sensors is not blocked and that nothing prevents light from reaching them. The chameleon welder’s mask should not have any dirt stains or dust layers on the surface

Chameleon mask filter darkening selection table.

Damage to the sensors is indicated by the following:

• filter response is slow;
• the darkening does not go away after the arc goes out;
• flickering is observed, the viewing window does not darken.

In this case, you cannot repair the sensors yourself; you must immediately contact a technician at the service center.

For many models, batteries can be easily replaced with your own hands. It is imperative to inspect the sensors, i.e. bring them to a bright light. This is required to ensure work safety, since the lack of darkening leads to eye injuries.

Sensors may be blocked if:

• the window begins to brighten when it is illuminated during operation;
• the dimming level does not correspond to the set mode;
• slow response;
• darkening is observed when there is no longer backlighting;
• flickering is observed.

It is easy to correct this situation: you need to clean the surface of the sensor itself and inspect the condition of the viewing window panel.

Contacting the service center

Additional options make repairs more difficult and increase the risk of mask failure. If the degree of darkening has decreased significantly, it is necessary to inspect the structure.

Some components cannot be repaired and require mandatory replacement. If you cannot do this yourself, you need to contact a service center. The guarantee is valid only for complete masks. If you managed to delve into it, you will have to pay for the service.

There is no point in undertaking repairs to the system board: this is a matter for professionals. It is better to contact the service center immediately. Unsuccessful DIY repairs can result in additional costs.

Marking of filters

The filter markings indicate the following characteristics:

1. Degree of darkness.
2. Optical glass type.
3. Light scattering indicator.
4. Uniformity of shading.
5. Angular dependence.

Darkness level

The main parameter by which glass is selected for certain jobs. Modern filters may use Russian or foreign markings, depending on the manufacturer. Domestic designations range from C1 to C13, but most often glasses with markers from C4 to C8 are used for welding masks.

European samples are marked from 7 to 16 DIN, although it is more likely to use filters with a rating from 8 to 14 DIN. The degree of shading is better for glasses with a larger number in the marking.

The best manufacturers of welding equipment

If welding is rarely done at home, and the duration of such work is short, then you can limit yourself to buying an inexpensive Chinese light filter, but you should not count on its high quality. It is better for professionals not to save money and purchase products from popular, reliable manufacturers:

1. 3M is an American company that produces not only light filters, but also shields, masks, and plates. All products are of high quality, so the manufacturer occupies a leading position in the Russian and world markets.
2. Svarog is a popular Russian company that produces protective equipment and welding equipment. The advantage of their products is their affordable price and high quality.
3. FUBAG is a German manufacturer that produces equipment and protective equipment for various industries and construction. Offers a large selection of replacement light filters and welding helmets.
4. Quattro Elementi is an Italian manufacturer. It produces modern models with fixed filters and those that can change the level of darkness in accordance with the strength of the light flux.
5. BRIMA is another German company popular in Russia, offering protective equipment used for welding by both amateurs and professionals.

produces masks and light filters.

ELITECH MS 500-1

A relatively inexpensive mask, distinguished not only by a very unusual design, but also by high quality. The original coloring makes it stand out from a number of similar gray and black models, so it will be problematic to confuse them. Works great both from a solar battery and from two AA batteries, which can be easily and quickly changed without wasting extra time. The available charge indicator allows you to monitor the condition of the batteries in order to replace them with new ones in time. It’s nice that the mask weighs 470 g - experienced welders know very well that every extra hundred grams leads to faster fatigue and pain in the neck.

Advantages:

• light weight;
• The light filter works quickly;
• excellent choice for home use;
• original design.

Flaws:

Not suitable for operation in temperatures below -5 degrees Celsius.

How to select a filter

The response time of the light filter is regulated by European standards EN379, according to which shading units are calculated in DIN units. When the illumination level increases from 4 to 13 DIN, the response inertia should not exceed 4 ms, and when moving to a more sensitive range (4-9 DIN) - 160-180 ms. Since the inertia of the human eye is at least 250 ms, the specified standards fully ensure effective protection of the welder’s visual organs. The performance of the filter is also determined by the intensity of its use. So, for professional welders, the response time should be no higher than 50 ms.

The next stage of selection is to analyze the specific characteristics of the filter. These include the optical class of the device, the degree of light scattering, the homogeneity class of the light flux and the permissible value of the scattering angle. All specified parameters are indicated on the body of the mask, with each subsequent characteristic separated by a slash from the previous one. At the end of the symbol there is a reference to the main standard (in this case EN379).

All of the above items are required.

What is a chameleon mask?

Unlike a standard shield, the Welding Chameleon takes welder protection to a new level. The principle of operation of such a mask is the polarization of liquid crystals. During provocation, they change direction and interfere with the effects of ultraviolet radiation. Masks in the expensive price segment use multi-layer protection, this ensures the most uniform darkening. And an additional filter provides blocking of infrared radiation.

The helmet has built-in sensors that detect the arc and provide constant eye protection. The entire structure is enclosed in a block, which is protected on both sides with the help of plastic light filters. You can carry out related work (with a grinder, a hammer) without removing the protective helmet from your head. Plastic filters require replacement over time, as they are consumables. The key point of the protective process is the speed at which the light filter operates. The response time of professional models is 1 millisecond.

The protective properties of a chameleon directly depend on the ambient temperature. If the temperature is below minus 10 degrees, the operation of the filter slows down. Conscientious manufacturers indicate the maximum operating temperature in the product data sheet. Adjustments can be made during the workflow. The buttons are conveniently located and easy to operate with tactile contact.

It is important to know! The mask must be stored in a heated room, otherwise its service life will be reduced.

Advantages and disadvantages of chameleons

Any equipment has its positive and negative qualities; in principle, ideal systems do not exist. The chameleon welding mask is no exception.

What does the market offer?

All welding helmets available on the tool market can be divided into three groups based on price-quality ratio:

• The cheapest, but with a very wide range of product quality fluctuations. Often they do not have certificates. These are mainly made in Taiwan or China.
• More expensive and quite high quality. They have proper Russian certificates. These are products from domestic manufacturers or South Korea.
• The most expensive and high-quality welding helmets are chameleon. As stated in the reviews of those who chose them - with a high degree of reliability. They have all the necessary documents. These are masks produced in European countries or under the direct control of European manufacturers (for example, TECHMEN or SPEEDGLAS).

In any case, no matter how expensive and outwardly reliable the mask may look, if during operation the eyes become irritated or a burning sensation appears, then this mask is not suitable for use. Her filter needs replacing.

What is its feature?

“Chameleons”, like their living prototypes, react very quickly to changes. When the arc is ignited for less than 1 second (professional standard), the filter is already darkened.

But every master can set a convenient filter sensitivity. Some people like to take it slow, while others want to finish the task quickly.

Since the mask may lighten immediately after welding is completed, be sure to allow more time for adjustments before starting work. This point is especially important for professionals.

If you miss this point, the heated metal may blind you, which will affect the entire process and productivity.

How to choose

Light filters for welding masks can be selected by marking. It has 4 digits. Each of them characterizes a certain indicator.

1. Optical class number. Determines the clarity of the image through the filter.
2. Level of light scattering. As the value of the number increases, the image received by the eyes deteriorates, the picture becomes cloudy. Best seen with marking value 1.
3. The level of darkness and the uniformity of its distribution over all glass surfaces.
4. Angular dependence of darkening, its degree when rotated by 15⁰.

Welding glass markings indicate how well the arc will be visible and the degree of eye protection while welding, including turning your head slightly.