La norma EN-ISO13855

The EN-ISO 13855 standard

Everything you need to know about the EN-ISO 13855 standard

The standard EN-ISO 13855 standard, within the scope of Industrial Safety, establishes the following methods for calculating the minimum safety distance for each type of safety device, based on the stopping time of the hazardous movement, which must be determined using a stopping time analyser and periodically verified through testing.

The units used in the formulas for calculating safety distances will henceforth be:

S: millimetres

T: milliseconds.

Each type of safety device has its own formula:

Safety Distance: Photoelectric Curtain

When determining the minimum safety distance, the resolution or detection range of the curtain’s smallest object must be taken into account:

Resolution d=<40 mm

The following formula will be applied:

S=(2000 x T) + 8(d – 14)

Where:

S = Safety distance between the detection plane and the hazardous area, in mm.

T = Total downtime in seconds: includes machine downtime + the response time of the photoelectric sensor.

d=Resolución de la cortina en mm.

La distancia mínima entre el plano de detección y la zona peligrosa debe ser en todo caso de 100 mm. (mín.)

If the distance obtained is S > 500 mm, the standard permits the use of the following formula, provided that the minimum distance of 500 mm is observed:

S=(1600 x T) + 8(d – 14)

Photoelectric curtains used to detect the start of hazardous movements must have a resolution of 14 mm or less and a minimum safety distance S of 150 mm, calculated using the following formula:

S=2000 x T

Resolution 40mm<d<70 mm

The standard classifies them as discrete-beam photoelectric devices and does not consider them suitable for detecting hand intrusion. The formula to be used in this case is:

S=(1600 x T) + (1200 – 0,4H)

H = height of the upper beam in mm.

In addition, the height of the lower beam must be 300 mm or less.

Single-beam or multi-beam photoelectric barrier

Solamente deben utilizarse para la detección de cuerpos o partes del cuerpo en dirección a la zona peligrosa.

The following formula will be applied:

S=(1600 x T) + (1200 – 0,4H)

H= altura del haz superior en mm.

Dependiendo del número de haces, las alturas a las que deben colocarse vienen reflejadas en la siguiente tabla:

Nº de haces Altura al suelo mm

4 300, 600, 900, 1200

3 300, 700, 1100

2 400, 900

Barrera fotoeléctrica de un sólo haz

This option can only be used for detecting people. The device must be positioned at a height of 750 mm above the reference plane.

The minimum safety distance is given by the following formula:

S=(1600 x T) + 1200

Safety Distance: Sensitive Mat

La norma EN ISO 13855 de dispositivos sensibles a la presión establece que el ancho mínimo para una alfombra sensible de seguridad es de 750 mm.

La distancia de seguridad S en mm se debe medir entre la zona de peligro y el borde exterior sensible de la alfombra. Esta distancia debe calcularse por la fórmula:

S=(1600 x T) + (1200 – 0,4H)

H = Height of the carpet above the floor in mm.

Floor-mounted

If the carpet is laid directly on the floor surface, the height H will be zero, and the following formula applies:

S=(1600 x T) + 1200

Installation on steps

If the carpet is laid on a step or raised platform above floor level, the general formula for carpets applies, but the minimum distance of 750 mm may be reduced by 0.4H, where H is the height of the carpet above the floor:

S=(1600 x T) + 1200

Two-handed control

If access to the hazardous area is protected by another safety device (such as a light curtain), the two-hand control may be positioned at a minimum distance S of 100 mm from the hazard.

Otherwise, the distance between the pushbuttons and the hazardous area shall be calculated using the following formula:

S=(1600 x T) + 250