a safety valve brands

Industry leading pressure and safety relief valve designs with over 140 years of technical and application expertise providing custom engineered solutions for O&G, Refining, Chemical, Petrochemical, Process and Power applications. Our designs meet global and local codes and standards (API 526; ASME Section I, IV & VIII; EN ISO 4126; PED & more). Gain insight into the performance of your pressure relief valves with wireless monitoring.

a safety valve brands

... -start valve with Series MX2 air treatment units without the need for additional connection interfaces. The soft-start valve is positioned upstream of the safety valves, ...

Two hands safety valve, which allows a safety use of two hands pneumatic controls (for example two push-button 3/2 N.C. to a certain distance) excluding false signals in case of push-button ...

The SI2 safety valve prevents the allowed operating pressure from being exceeded by more than 10%. If, after opening, the adjusted response pressure falls ...

... stainless steel full-lift clean service safety valve designed to AD Merkblatt A2 and TRD 421 standards and suitable for pure steam, vapour and inert gases.

Insert style flow control valves are comprised of a precision orifice in parallel with a check valve, combined into a single component. Each is designed for easy installation into metal housings using ...

Press-in style flow control valves are comprised of a precision flow orifice in parallel with a check valve, combined into a single component. Each part is designed for easy installation into plastic ...

If you have been searching for a safety release valve that you can use to reduce short-term pressure surges successfully and diminish the effects of gas leaks, this is the product for you. With a pe of ...

... have been type tested as well. These pressure regulators have safety valves which will slam shut in the event of emergencies, such as the gas reaching too high a pressure level. The valve ...

This product has hydraulically actuated class A gas safety valves to EN 161 used for automatic shut-off. It shuts off when unstimulated for gas and air, or even biologically produced methane. It has AISi ...

The S 104 Safety Shut Off valve is mainly used to avoid any damage to components as well as to avoid too high or too low pressure in the gas train. This could cause high financial losses and/or injured ...

The S50 Safety Shut Off valve is mainly used to avoid any damage to components as well as to avoid too high or too low pressure in the gas train. This could cause high financial losses and/or injured ...

The S100 Safety Shut Off valve is mainly used to avoid any damage to components as well as to avoid too high or too low pressure in the gas train. This could cause high financial losses and/or injured ...

... Pressure Safety Valve + Rupture Disk is protected and may be utilized autonomously as essential security gadgets or in conjunction. There are 3 possible combinations. The first combinations ...

Excavator pipe-rupture valves prevent uncontrolled cylinder movement in the event that a pipe or hose bursts. The ESV valve fulfills all of the requirements of the ISO 8643 and EN 474-5 standards for ...

Material: Body- CF8M; Valve Seat- CF8M Métal Seat, PTFE Soft Seat available Orifice Size: fc"(15mm), 3/4M(20mm), l"(25mm), l1/4,’(32mm)I ltë”(40mm), ...

The Safety valves from ATOS are designed to guarantee protection for application on various devices, especially those that monitor spool position. They are also recommended for hydraulic ...

a safety valve brands

Distributor of hydraulic press safety, quick opening safety, rotary and safety valves. Amerigear®, Boston Gear®, Carlisle®, DeMag®, Desch® and IMI Norgren®, pneumatic, double action, quick release and flow control valves also provided. Repair and preventative maintenance services are offered. Value added services such as custom barcoding, CAD capabilities, OEM assembly, plant surveys and third party logistics are also available. Serves the metal processing, metal service center, paper mill and paper converting, canning, grinding, commercial laundry, marine, oil and gas and material handling industries. Vendor managed inventory (VMI) programs available. Kanban delivery.

a safety valve brands

Emergency situations are not the only times relief valves are active; once installed they continuously regulate the flow of substance. They can also be pre-set to open when the pressure or temperature gets to a certain point that may be dangerous. Generally valves are placed on or near the pump head of the hose, pipe or tube. A wide variety of relief valve designs exist, although most resemble ball-check valves, swing check valves or diaphragm valves.

This last is particularly useful when controlling a flow of fluids that contains suspended solids. Most relief valves are spring operated, as are the majority of check valves. One specialized type of relief valve is known as a vacuum relief valve. As opposed to a normal relief valve, which relieves high pressure, a vacuum relief valve is used to relieve dangerously low pressures, or vacuums, by inserting air or an inert gas.

Like every other type of check valve, relief valves may be constructed from a variety of materials, including PVC, brass, ductile iron, copper, polyethylene, polypropylene, aluminum, steel, stainless steel and rubber. Which raw substance is used to produce each relief valve depends on the environment said relief valve will be in. The wrong product could result in erosion or contamination of the process stream. However, as long as research is done, finding the appropriate type of relief valve is possible. Every plumbing or fluid transfer application in the industrial, commercial and domestic arenas employ or will employ check valves. In fact, check valves of all kinds are an essential part of every day life. Because they need not be supervised to function and prevent product malfunction, check valves are not only desirable but often required by law to ensure the safety of water, gas and pressure applications.

a safety valve brands

The RV10 safety relief valve is well-suited for overpressure protection of production equipment, including compressors, scrubbers, separators, pipelines or anywhere overpressure protection may be required.

a safety valve brands

Of all the challenges you face keeping your customers’ plants operating at full capacity, safety and relief valves shouldn’t be one of them. NASVI’s job is to give you the confidence that your valve supply chain is rock solid regardless the pressure it’s under.

Expect expert service, the most extensive inventory in the nation and emergency service whenever needed. That’s how we’ve got our customers’ backs since 1975.

a safety valve brands

Also known as pressure relief valves (PRV), pressure safety valves (PSV), and safety valves, these systems act as a safety measure. They relieve excess pressure from equipment failure, process upset, or fire by opening an auxiliary passage to divert the fluid (liquid, gas, steam or air) away from the pressure vessel. Once the pressure in the vessel is released and the danger is over the relief valve closes itself. Emergency situations are not the only times relief valves are active; once installed they continuously regulate the flow of substance. They can also be pre-set to open when the pressure or temperature gets to a certain point that may be dangerous.

Generally valves are placed on or near the pump head of the hose, pipe, or tube. A wide variety of relief valve designs exist, although most resemble ball-check valves, swing check valves or diaphragm valves. This last is particularly useful when controlling a flow of fluids that contains suspended solids. Most relief valves are spring operated, as are the majority of check valves. One specialized type of relief valve is known as a vacuum relief valve. As opposed to a normal relief valve, which relieves high pressure, a vacuum relief valve is used to relieve dangerously low pressures, or vacuums, by inserting air or an inert gas.

Which raw substance is used to produce each relief valve depends on the environment said relief valve will be in. The wrong product could result in erosion or contamination of the process stream. However, as long as research is done, finding the appropriate type of relief valve is possible. Every plumbing or fluid transfer application in the industrial, commercial, and domestic arenas employ or will employ check valves. In fact, check valves of all kinds are an essential part of every day life. Because they need not be supervised to function and prevent product malfunction, check valves are not only desirable but often required by law to ensure the safety of water, gas, and pressure applications.

a safety valve brands

This page lists the ApprovedPressure and Safety Relief ValveManufacturers (vendors), also provides inspection and test advice to thePressure and Safety Relief Valvepurchasers buying from vendors, suppliers and distributors.

When you are buying a finished goods or equipment from a vendor, supplier or distributor, then there is no chance to witness some important test and inspection in the manufacturing process.

this website. The vendor lists are categorized in 5 major categories, e.g.Raw Material and Static Equipment, Rotary Equipment,Electrical Equipment,Instrumental Equipment andSkid Mounted or Package Unit.

a safety valve brands

With more than 1,050 employees and 130,000 safety valves produced per year, LESER is the largest manufacturer of safety valves in Europe and one of the leading companies in its industry worldwide.

LESER offers spring loaded and pilot operated safety valves for all industrial applications according to the Pressure Equipment Directive and ASME XIII. Major companies in the chemical, oil and gas, petrochemical, energy, technical gases, LNG/LPG, pharmaceutical, food and beverage, shipbuilding and heating and air conditioning industries use LESER safety valves.

LESER safety valves are developed for the international market in Hamburg and manufactured in the modern plant in Hohenwestedt/Germany. In addition, LESER produces safety valves to the same standards in India and China for the local markets. Nine subsidiaries and offices in Europe, America, the Middle East and Asia as well as authorized contacts in over 80 countries guarantee competent customer advice and fast, reliable deliveries.

a safety valve brands

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a safety valve brands

Taylor Valve Technology® is a manufacturer leader in high-quality industrial valves. We deliver safety relief, high-pressure relief, and back pressure relief valves. Our wide array of choke and control valves and pilot-operated valve products are second to none. Products are designed for demanding industrial needs, meeting quality API and ASME Code requirements. High-demand oil & gas industry, chemical plants, power generators, and the processing industry depend on our valves for consistency and durability. Get effective flow control of liquid, steam, and gas. Valves ship from the Taylor Valve Technology, Inc. United States facility. Delivering worldwide, you can depend on quick turnaround times.

a safety valve brands

Consolidated boasts 140+ years of dedicated Pressure Relief Valve (PRV) Engineering and Manufacturing expertise.  We know overpressure protection!  With more than 10 major first-to-market products and features, Consolidated continues to deliver innovative technical solutions to the world"s most challenging overpressure protection applications.  When combined with the expertise and full-scale service of the Green Tag Center (GTC) Network, Consolidated is able to provide a comprehensive approach to Valve Lifecycle Management (VLM) that is second to none.

Comprehensive Valve Lifecycle Management (VLM) enabled by state-of-the-art tools and delivered by the unparalleled Consolidated Green Tag Center (GTC) Network, Consolidated supports our product throughout the entire lifecycle.

a safety valve brands

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a safety valve brands

There is a wide range of safety valves available to meet the many different applications and performance criteria demanded by different industries. Furthermore, national standards define many varying types of safety valve.

The ASME standard I and ASME standard VIII for boiler and pressure vessel applications and the ASME/ANSI PTC 25.3 standard for safety valves and relief valves provide the following definition. These standards set performance characteristics as well as defining the different types of safety valves that are used:

ASME I valve - A safety relief valve conforming to the requirements of Section I of the ASME pressure vessel code for boiler applications which will open within 3% overpressure and close within 4%. It will usually feature two blowdown rings, and is identified by a National Board ‘V’ stamp.

ASME VIII valve- A safety relief valve conforming to the requirements of Section VIII of the ASME pressure vessel code for pressure vessel applications which will open within 10% overpressure and close within 7%. Identified by a National Board ‘UV’ stamp.

Full bore safety valve - A safety valve having no protrusions in the bore, and wherein the valve lifts to an extent sufficient for the minimum area at any section, at or below the seat, to become the controlling orifice.

Conventional safety relief valve -The spring housing is vented to the discharge side, hence operational characteristics are directly affected by changes in the backpressure to the valve.

Balanced safety relief valve -A balanced valve incorporates a means of minimising the effect of backpressure on the operational characteristics of the valve.

Pilot operated pressure relief valve -The major relieving device is combined with, and is controlled by, a self-actuated auxiliary pressure relief device.

Power-actuated safety relief valve - A pressure relief valve in which the major pressure relieving device is combined with, and controlled by, a device requiring an external source of energy.

Standard safety valve - A valve which, following opening, reaches the degree of lift necessary for the mass flowrate to be discharged within a pressure rise of not more than 10%. (The valve is characterised by a pop type action and is sometimes known as high lift).

Full lift (Vollhub) safety valve -A safety valve which, after commencement of lift, opens rapidly within a 5% pressure rise up to the full lift as limited by the design. The amount of lift up to the rapid opening (proportional range) shall not be more than 20%.

Direct loaded safety valve -A safety valve in which the opening force underneath the valve disc is opposed by a closing force such as a spring or a weight.

Proportional safety valve - A safety valve which opens more or less steadily in relation to the increase in pressure. Sudden opening within a 10% lift range will not occur without pressure increase. Following opening within a pressure of not more than 10%, these safety valves achieve the lift necessary for the mass flow to be discharged.

Diaphragm safety valve -A direct loaded safety valve wherein linear moving and rotating elements and springs are protected against the effects of the fluid by a diaphragm

Bellows safety valve - A direct loaded safety valve wherein sliding and (partially or fully) rotating elements and springs are protected against the effects of the fluids by a bellows. The bellows may be of such a design that it compensates for influences of backpressure.

Controlled safety valve - Consists of a main valve and a control device. It also includes direct acting safety valves with supplementary loading in which, until the set pressure is reached, an additional force increases the closing force.

Safety valve - A safety valve which automatically, without the assistance of any energy other than that of the fluid concerned, discharges a quantity of the fluid so as to prevent a predetermined safe pressure being exceeded, and which is designed to re-close and prevent further flow of fluid after normal pressure conditions of service have been restored. Note; the valve can be characterised either by pop action (rapid opening) or by opening in proportion (not necessarily linear) to the increase in pressure over the set pressure.

Direct loaded safety valve -A safety valve in which the loading due to the fluid pressure underneath the valve disc is opposed only by a direct mechanical loading device such as a weight, lever and weight, or a spring.

Assisted safety valve -A safety valve which by means of a powered assistance mechanism, may additionally be lifted at a pressure lower than the set pressure and will, even in the event of a failure of the assistance mechanism, comply with all the requirements for safety valves given in the standard.

Supplementary loaded safety valve - A safety valve that has, until the pressure at the inlet to the safety valve reaches the set pressure, an additional force, which increases the sealing force.

Note; this additional force (supplementary load), which may be provided by means of an extraneous power source, is reliably released when the pressure at the inlet of the safety valve reaches the set pressure. The amount of supplementary loading is so arranged that if such supplementary loading is not released, the safety valve will attain its certified discharge capacity at a pressure not greater than 1.1 times the maximum allowable pressure of the equipment to be protected.

Pilot operated safety valve -A safety valve, the operation of which is initiated and controlled by the fluid discharged from a pilot valve, which is itself, a direct loaded safety valve subject to the requirement of the standard.

The common characteristic shared between the definitions of conventional safety valves in the different standards, is that their operational characteristics are affected by any backpressure in the discharge system. It is important to note that the total backpressure is generated from two components; superimposed backpressure and the built-up backpressure:

Subsequently, in a conventional safety valve, only the superimposed backpressure will affect the opening characteristic and set value, but the combined backpressure will alter the blowdown characteristic and re-seat value.

The ASME/ANSI standard makes the further classification that conventional valves have a spring housing that is vented to the discharge side of the valve. If the spring housing is vented to the atmosphere, any superimposed backpressure will still affect the operational characteristics. Thiscan be seen from Figure 9.2.1, which shows schematic diagrams of valves whose spring housings are vented to the discharge side of the valve and to the atmosphere.

By considering the forces acting on the disc (with area AD), it can be seen that the required opening force (equivalent to the product of inlet pressure (PV) and the nozzle area (AN)) is the sum of the spring force (FS) and the force due to the backpressure (PB) acting on the top and bottom of the disc. In the case of a spring housing vented to the discharge side of the valve (an ASME conventional safety relief valve, see Figure 9.2.1 (a)), the required opening force is:

In both cases, if a significant superimposed backpressure exists, its effects on the set pressure need to be considered when designing a safety valve system.

Once the valve starts to open, the effects of built-up backpressure also have to be taken into account. For a conventional safety valve with the spring housing vented to the discharge side of the valve, see Figure 9.2.1 (a), the effect of built-up backpressure can be determined by considering Equation 9.2.1 and by noting that once the valve starts to open, the inlet pressure is the sum of the set pressure, PS, and the overpressure, PO.

In both cases, if a significant superimposed backpressure exists, its effects on the set pressure need to be considered when designing a safety valve system.

Once the valve starts to open, the effects of built-up backpressure also have to be taken into account. For a conventional safety valve with the spring housing vented to the discharge side of the valve, see Figure 9.2.1 (a), the effect of built-up backpressure can be determined by considering Equation 9.2.1 and by noting that once the valve starts to open, the inlet pressure is the sum of the set pressure, PS, and the overpressure, PO.

Balanced safety valves are those that incorporate a means of eliminating the effects of backpressure. There are two basic designs that can be used to achieve this:

Although there are several variations of the piston valve, they generally consist of a piston type disc whose movement is constrained by a vented guide. The area of the top face of the piston, AP, and the nozzle seat area, AN, are designed to be equal. This means that the effective area of both the top and bottom surfaces of the disc exposed to the backpressure are equal, and therefore any additional forces are balanced. In addition, the spring bonnet is vented such that the top face of the piston is subjected to atmospheric pressure, as shown in Figure 9.2.2.

The bellows arrangement prevents backpressure acting on the upper side of the disc within the area of the bellows. The disc area extending beyond the bellows and the opposing disc area are equal, and so the forces acting on the disc are balanced, and the backpressure has little effect on the valve opening pressure.

Bellows failure is an important concern when using a bellows balanced safety valve, as this may affect the set pressure and capacity of the valve. It is important, therefore, that there is some mechanism for detecting any uncharacteristic fluid flow through the bellows vents. In addition, some bellows balanced safety valves include an auxiliary piston that is used to overcome the effects of backpressure in the case of bellows failure. This type of safety valve is usually only used on critical applications in the oil and petrochemical industries.

In addition to reducing the effects of backpressure, the bellows also serve to isolate the spindle guide and the spring from the process fluid, this is important when the fluid is corrosive.

Since balanced pressure relief valves are typically more expensive than their unbalanced counterparts, they are commonly only used where high pressure manifolds are unavoidable, or in critical applications where a very precise set pressure or blowdown is required.

This type of safety valve uses the flowing medium itself, through a pilot valve, to apply the closing force on the safety valve disc. The pilot valve is itself a small safety valve.

The diaphragm type is typically only available for low pressure applications and it produces a proportional type action, characteristic of relief valves used in liquid systems. They are therefore of little use in steam systems, consequently, they will not be considered in this text.

The piston type valve consists of a main valve, which uses a piston shaped closing device (or obturator), and an external pilot valve. Figure 9.2.4 shows a diagram of a typical piston type, pilot operated safety valve.

The piston and seating arrangement incorporated in the main valve is designed so that the bottom area of the piston, exposed to the inlet fluid, is less than the area of the top of the piston. As both ends of the piston are exposed to the fluid at the same pressure, this means that under normal system operating conditions, the closing force, resulting from the larger top area, is greater than the inlet force. The resultant downward force therefore holds the piston firmly on its seat.

If the inlet pressure were to rise, the net closing force on the piston also increases, ensuring that a tight shut-off is continually maintained. However, when the inlet pressure reaches the set pressure, the pilot valve will pop open to release the fluid pressure above the piston. With much less fluid pressure acting on the upper surface of the piston, the inlet pressure generates a net upwards force and the piston will leave its seat. This causes the main valve to pop open, allowing the process fluid to be discharged.

When the inlet pressure has been sufficiently reduced, the pilot valve will reclose, preventing the further release of fluid from the top of the piston, thereby re-establishing the net downward force, and causing the piston to reseat.

Pilot operated safety valves offer good overpressure and blowdown performance (a blowdown of 2% is attainable). For this reason, they are used where a narrow margin is required between the set pressure and the system operating pressure. Pilot operated valves are also available in much larger sizes, making them the preferred type of safety valve for larger capacities.

One of the main concerns with pilot operated safety valves is that the small bore, pilot connecting pipes are susceptible to blockage by foreign matter, or due to the collection of condensate in these pipes. This can lead to the failure of the valve, either in the open or closed position, depending on where the blockage occurs.

The terms full lift, high lift and low lift refer to the amount of travel the disc undergoes as it moves from its closed position to the position required to produce the certified discharge capacity, and how this affects the discharge capacity of the valve.

A full lift safety valve is one in which the disc lifts sufficiently, so that the curtain area no longer influences the discharge area. The discharge area, and therefore the capacity of the valve are subsequently determined by the bore area. This occurs when the disc lifts a distance of at least a quarter of the bore diameter. A full lift conventional safety valve is often the best choice for general steam applications.

The disc of a high lift safety valve lifts a distance of at least 1/12th of the bore diameter. This means that the curtain area, and ultimately the position of the disc, determines the discharge area. The discharge capacities of high lift valves tend to be significantly lower than those of full lift valves, and for a given discharge capacity, it is usually possible to select a full lift valve that has a nominal size several times smaller than a corresponding high lift valve, which usually incurs cost advantages.Furthermore, high lift valves tend to be used on compressible fluids where their action is more proportional.

In low lift valves, the disc only lifts a distance of 1/24th of the bore diameter. The discharge area is determined entirely by the position of the disc, and since the disc only lifts a small amount, the capacities tend to be much lower than those of full or high lift valves.

Except when safety valves are discharging, the only parts that are wetted by the process fluid are the inlet tract (nozzle) and the disc. Since safety valves operate infrequently under normal conditions, all other components can be manufactured from standard materials for most applications. There are however several exceptions, in which case, special materials have to be used, these include:

Cast steel -Commonly used on higher pressure valves (up to 40 bar g). Process type valves are usually made from a cast steel body with an austenitic full nozzle type construction.

For all safety valves, it is important that moving parts, particularly the spindle and guides are made from materials that will not easily degrade or corrode. As seats and discs are constantly in contact with the process fluid, they must be able to resist the effects of erosion and corrosion.

For process applications, austenitic stainless steel is commonly used for seats and discs; sometimes they are ‘stellite faced’ for increased durability. For extremely corrosive fluids, nozzles, discs and seats are made from special alloys such as ‘monel’ or ‘hastelloy’.

The spring is a critical element of the safety valve and must provide reliable performance within the required parameters. Standard safety valves will typically use carbon steel for moderate temperatures. Tungsten steel is used for higher temperature, non-corrosive applications, and stainless steel is used for corrosive or clean steam duty. For sour gas and high temperature applications, often special materials such as monel, hastelloy and ‘inconel’ are used.

A key option is the type of seating material used. Metal-to-metal seats, commonly made from stainless steel, are normally used for high temperature applications such as steam. Alternatively, resilient discs can be fixed to either or both of the seating surfaces where tighter shut-off is required, typically for gas or liquid applications. These inserts can be made from a number of different materials, but Viton, nitrile or EPDM are the most common. Soft seal inserts are not generally recommended for steam use.

Standard safety valves are generally fitted with an easing lever, which enables the valve to be lifted manually in order to ensure that it is operational at pressures in excess of 75% of set pressure. This is usually done as part of routine safety checks, or during maintenance to prevent seizing. The fitting of a lever is usually a requirement of national standards and insurance companies for steam and hot water applications. For example, the ASME Boiler and Pressure Vessel Code states that pressure relief valves must be fitted with a lever if they are to be used on air, water over 60°C, and steam.

A standard or open lever is the simplest type of lever available. It is typically used on applications where a small amount of leakage of the fluid to the atmosphere is acceptable, such as on steam and air systems, (see Figure 9.2.5 (a)).

Where it is not acceptable for the media to escape, a packed lever must be used. This uses a packed gland seal to ensure that the fluid is contained within the cap, (see Figure 9.2.5 (b)).

For service where a lever is not required, a cap can be used to simply protect the adjustment screw. If used in conjunction with a gasket, it can be used to prevent emissions to the atmosphere, (see Figure 9.2.6).

A test gag (Figure 9.2.7) may be used to prevent the valve from opening at the set pressure during hydraulic testing when commissioning a system. Once tested, the gag screw is removed and replaced with a short blanking plug before the valve is placed in service.

The amount of fluid depends on the particular design of safety valve. If emission of this fluid into the atmosphere is acceptable, the spring housing may be vented to the atmosphere – an open bonnet. This is usually advantageous when the safety valve is used on high temperature fluids or for boiler applications as, otherwise, high temperatures can relax the spring, altering the set pressure of the valve. However, using an open bonnet exposes the valve spring and internals to environmental conditions, which can lead to damage and corrosion of the spring.

When the fluid must be completely contained by the safety valve (and the discharge system), it is necessary to use a closed bonnet, which is not vented to the atmosphere. This type of spring enclosure is almost universally used for small screwed valves and, it is becoming increasingly common on many valve ranges since, particularly on steam, discharge of the fluid could be hazardous to personnel.

Some safety valves, most commonly those used for water applications, incorporate a flexible diaphragm or bellows to isolate the safety valve spring and upper chamber from the process fluid, (see Figure 9.2.9).

An elastomer bellows or diaphragm is commonly used in hot water or heating applications, whereas a stainless steel one would be used on process applications employing hazardous fluids.

a safety valve brands

Pressure relief valves are primarily designed to protect equipment, process, property, the environment, and life. Allowing processing facilities to operate safely, pressure relief valves often act as the last line of defence against system overpressure which can cause catastrophic damage.

Pressure relief valves operate by opening at a predetermined set pressure, relieving pressure by releasing process media until system pressure drops to normal operating level. At this point, the valve closes, successfully preventing damage to the equipment they are designed to protect.