BIFMA International Standard Chair Test Guide

BIFMA International Standard Chair Test Guide

Chair Type

I(back and seat can retreat at the same time)

II(fixed seat, recoil)

III

(the back and the seat are fixed and cannot be reclined)

Back static strength test (for type I chairs)

Test Methods:

1. Put the chair vertically on the test platform, fix the wheel, the back and the armrest need not be fixed;

2. If the chair has any tuning function, except that the back height must be adjusted to the maximum or 406mm (16.0′′) (minimum of the two), the rest are adjusted to the values under normal use.

3.After step 2 is completed, two points with a height of 406mm (16.0′′) and 452mm (17.8′′) are determined based on the vertical midline of the seatback.

Determine the method as follows:

(a) If the height ≧ 452mm (17.8′′), this point is 406mm (16′′), as shown in Figure 1;

(b) If the height is < 452mm (17.8′′), this point is the highest point of the seatback, as shown in Figure 2;

(3) If there is a rotating axis behind the chair, and the axis and the vertical backward angle ≤30°, The points are identified as (a) and (b), and vice versa, the point is located at the axis of rotation of the seat back. As shown in Figure 3

(4) When the seat back is in the maximum reclining position, the force direction should be 90°± 10° with the back (Figure 4)

(5) If the test system uses a hanging wire or runner, the wire must be at least 762mm (30′′) long.

Note: When the design of the chair does not allow the load to transfer force to its bearing surface, a height of 89mm ± 13mm may be used to extend the bearing surface.

(6) test requirements: In the case of the institution is not locked, the chair back to the maximum tilt angle and fixed, and then loaded as follows:

(A) functional test

Force F=890 N (91Kg), time T=1 minute, After the test, the function of the chair is normal, otherwise it is deemed as unqualified

(B) verification test

Force F=1334 N (136Kg), time T = 1 minute, After the test, the structure of the chair can not be changed or damaged greatly, and the function is acceptable.

6. Back static strength test (applicable to Class II and Class III chairs)

Test Methods:

a) Place the chair vertically on the test bench, securing the wheels, but not the back and armrests.

b) If the chair has an adjustment function, except that the height of the seat back needs to be adjusted to the maximum or 406mm (16") (minimum of the two), all items are adjusted to normal use levels.

c) After step 2 is completed, two points with a distance of 406mm (16") and 452mm (17.8") from the height of the seat are determined on the vertical center line of the seatback. The determination method is as follows:

(a) Height ≥ 452mm (17.8"), then the point is 406mm (16"), as shown in Figure 1.

(b) Height < 452mm (17.8"), this point is the highest point of the seatback, as shown in Figure 2;

(c) If the back surface of the chair has an axis of rotation and the angle of backward inclination is 30° with the vertical direction, it is determined that the point is the same as (1) and (2); otherwise, the point is located at the axis of the back rotation. As shown in Figure 3

d) When the seat back is at the maximum tilt angle, the force direction should be 90°± 10° with the back (as shown in figure 4)

e) If the test system is in the form of a hanging wire or a runner, the wire used must be at least 750 mm (30 in.) long.

Note: When the design of the chair does not allow the load to transfer force to its bearing surface, a height of 89mm ± 13mm may be used to extend the bearing surface.

f) Test requirements

When the mechanism is not locked, adjust the back of the chair to the maximum tilt angle and lock it. Then press the step to load:

(a) Functional test:

Force F=667N (68Kg), time T=1 minute

After the test is completed, the functions of the chair are used normally. If a malfunction occurs, it is considered as unqualified.

(B) Inspection and testing

Force F=1112N (113Kg.), time T = 1 minute

After the test is completed, there must be no major changes or damage to the structure of the chair, but functional problems may be acceptable.

7. Five-star claw static strength test

Test Methods:

a) Place the five-star claws on the test bench and the star claws do not touch the test bench

Remove the casters or pulleys, retain the handles, and place them in the slots. The height of the handles should be at least five.

(Install as shown in the figure below); If the pulley is not removable, fix it with something

b) remove the seat support mechanism and seat height adjustment device;

c) The center of the five-star claw should be able to move vertically and the chair legs should be able to move left and right.

d) The grooves of the fixed casters must be equal to the height of the original casters.

e)Test: First increase the force F = 17,640N (1800Kg), time T = 1 minute, then release the force;

Re-force F = 17,640N (1800Kg), time T = 1 minute, then release force

After the completion of the test, the five-star claw structure could not be greatly affected by unpredictable damage; the bottom of the five-star claw did not touch the test bench during the test.

8, drop test

Test Methods:

1 chair on the test bench;

2 If the chair seat has a lifting function, adjust it to the highest; if there are other adjustment functions, adjust it to normal use; the chair with wheels adjusts the wheels to the worst state of stability (usually 90° to the chair support) position)

3 Place a sandbag with a diameter of approximately 400 mm (16") directly above the seat. The distance between the sandbag and the back of the seat should not be more than 13 mm (0.51"), but you cannot touch the back of the chair in a fall. See the figure below.

4 test requirements are as follows:

(1) functional test

A. Sandbag weight F = 102KG (225lbf.), increased to 152mm (6"), dropped once

B. If the chair has a lifting function, do it once again in the lowest position.

C. After the test, the chair functions normally. All functional problems are considered unqualified

(2) verification test

A. The sandbag weight F = 136 KG (300 lbf.), raised to 152 mm (6"), dropped once.

B. If the chair has a lifting function, do it once again in the lowest position.

C. After the test, the chair can't appear structural changes and unpredictable damage, but the functional problems are acceptable.

9, rotation durability test

Test Methods:

1 chair flat on the test bench and fixed;

2 If the chair has lifting function, adjust to the highest, and the other adjustable functions are adjusted to normal use.

3 Load 102KG (225 lbf..) on the seat at a distance of 51-64mm (2"-2.5") from the axis of rotation. See the figure below:

4 The device operating speed is set to 5-15 times per minute (rotate 360 degrees once)

5 test requirements are as follows:

1. Seat with lift function, turn 60,000 times at the lowest point and highest point

2. Without lifting function, test 120,000 times;

3. After the test is completed, the chair function is normal, if the chair function is abnormal, it is unqualified

10, reversing the endurance test

Description: This test is applicable to chairs with adjustable back angles for Class I and Class II. Through the testing of the organization, its ability to resist wear and metal fatigue was verified.

Test Methods:

1 chair fixed on the test platform

2 Adjust the seat to normal use

3 Fix the push rod of the test device to the position that can act on the back of the chair

4 Fix the weight of 102KG (225lbf.) in the center of the seat

5 Adjusting the reclining mechanism push rod to the point of maximum tilting of the chair just to be able to invert the chair without hitting the mechanism

Test steps:

Test the chair 300,000 times at a rate of 10-30 times per minute, and adjust the chair appropriately if necessary during the test

Test Results:

After the test, the agency can use it normally and there is no abnormal function. Otherwise it is deemed as unqualified

11, seat durability test (including impact test and seat angle loading test)

(1) Impact test

1 Place the chair on the test bench and fix it. If there are wheels, adjust the wheels to the least stable condition (usually 90° to the foot)

2 If the chair has a lifting function, adjust the height to normal use.

3 If the cushion thickness is less than 44mm (1.75"), a cotton pad can be added to the cushion to a thickness of 50mm ± 6mm (2" ± 0.25");

4 Put a sandbag with a diameter of approximately 400mm (16") and a weight of 57KG (125lbf.) on the test equipment above the seat. The position should not be more than 13mm (0.51") from the back of the chair. You must not touch the back when you fall.

Note: Nylon nets and flexible plastic seats are not considered cushion materials, so apply a cotton pad to increase the thickness for testing.

5 The operating speed of the equipment is 100,000 times;

6 The function of the chair is normal after the test. If there is abnormality, it is unqualified.

B. Seat angle loading test

1 After the impact test is completed, perform a seat angle loading test

2 as shown, through a diameter of734N (75Kg) force is applied to the front corner of 203mm ± 13mm (8"± 0.51"), and the armrest can be removed if necessary

3 Each test 20,000 times for each position, one position must be measured and another position must be