|Key DDA Information and guidance for the provision of suitable office furniture and office layout.|
Listed below are some points to consider for reception areas, door widths and desk height accessibility which relates to the law that companies need to be compliant with.
Doors to accessible entrances
Doors to the principal or alternative accessible entrance should be accessible to all, particularly wheelchair users and people with limited physical dexterity. Entrance doors may be manually operated without powered assistance, or power operated under manual or automatic control.
Where doors are required to be self-closing, a power operated door opening and closing system is used when through calculation and experience it appears that it will not be possible otherwise for a person to open the door using a force no greater than 20N at the leading edge.
The effective clear width through a single leaf door, or one leaf of a double leaf door should be in accordance with the Table 1 shown below and the rules for measurement should be in accordance with the Diagram 9 shown below.
There are various reasons for providing a lobby:
· To limit air infiltration
· To maintain comfort by controlling draughts
· To increase security
· To provide transitional lighting
A lobby should be large enough and of a shape to allow a wheelchair user to move clear of one door before opening the second door. The lobby should also be capable of accommodating a companion helping a wheelchair user to open doors and guide the wheelchair through. The minimum length of the lobby is related to the chosen door size, the swing of each door, the projection of the door into the lobby and the size of an occupied wheelchair with a companion pushing. Where both doors to a lobby are automatic sliding doors, the length can be reduced as no door swings are involved, nor is space required for manual operation. Similarly, if ‘reduced swing’ door sets are used, the length can be reduced because the projection of the door into the lobby is reduced.
A lobby’s length with single swing doors should be in accordance with Diagram 10.
With double swing doors it should be at least (DP1 + DP2 + 1570mm).
If a lobby’s width (excluding any projections into the space) is at least 1200mm (or DL1 or DL2) + 300mm) whichever is greater when single leaf doors are used, and at least 1800mm when double leaf doors are used.
Glazing within a lobby must not create distracting reflections.
Floor surface materials within the lobby must not impede the movement of wheelchairs, e. g. not coir matting, and changes in floor materials must not create a potential trip hazard.
The floor surface should help to remove rainwater from shoes and wheelchairs.
Where matt wells are provided the surface of the mat must be level with the surface of any adjacent floor finish.
Any columns, ducts and similar full height elements that project into the lobby by more than 100mm must be protected by a visually contrasting guard rail.
A reception area should not only be easily accessible but also convenient to use.
Glazed screens in front of the reception point, or light sources or reflective wall surfaces, such as glazed screens, located behind the reception point could compromise the ability of a person with a hearing impairment to lip read or follow sign language.
A reception point can be located away from the principal entrance (while still providing a view of it) where there is a risk that external noise will be a problem.
A reception point must be easily identifiable from the entrance doors or lobby and the approach to it must be direct and free from obstructions.
The design of the approach to any reception point must allow space for wheelchair users to gain access to the reception point.
The clear manoeuvring space in front of any reception desk or counter must be 1200mm deep and 1800mm wide if there is a knee recess at least 500mm deep, or 1400mm deep and 2200mm wide if there is no knee recess.
A reception desk or counter must be designed to accommodate both standing and seated visitors such that at least one section of the counter is at least 1500mm wide, with it’s surface no higher that 760mm and a knee recess not less than 700mm above floor level.
A reception point needs to provide a hearing enhancement system, e. g. an induction loop.
The floor surface must be slip resistant.
There are numerous different types of desks and receptions available suitable for people in wheelchairs. Desks are available with adjustable height tops and DDA compliant receptions can be bought ready made with a recess for wheelchair access and are available in either wood veneer of laminate.
Some examples are shown below: -
Doors can be potential barriers and should be avoided whenever appropriate. If doors are required, the use of self-closing devices should be minimised. Where closing devices are needed for fire control, electrically powered hold open devices or swing-free closing devises should be used as appropriate. These are devices whose closing mechanism is only activated in case of emergency. Low energy powered door systems may be used in locations not subject to frequent use or heavy traffic as the opening and closing action is relatively slow.
People with impaired sight should be able to identify the door opening within a wall as well as the leading edge of the door.
Where internal doors need to be opened manually, the opening force at the leading edge of the door must not exceed 20N.
The effective clear width through a single leaf door or one leaf of a double leaf door must be in accordance with Table 1 and Diagram 9.
The must be an unobstructed space of at least 300mm on the pull side of the door between the leading edge of the door and any return wall, unless the door has power-controlled opening.
If the door is fitted with a latch, the door opening furniture can be operated with one hand using a closed fist, e. g. a lever handle.
All door opening furniture must contrast visually with the surface of the door.
The door frame must contrast visually with the surrounding wall.
The surface of the leading edge of any door that is not self-closing, or is likely to be held open must contract visually with the other door surfaces and its surroundings.
Where appropriate in door leaves or side panels wider than 450mm, vision panels towards the leading edge of the door have vertical dimensions which include at least the minimum zone, or zones of visibility between 500mm and 1500mm from the floor, if necessary interrupted between 800mm and 1150mm above the floor, e. g. to accommodate and intermediate horizontal rail (see Diagram 9).
If a door is made of glass it must be clearly defined with manifestation on the glass at two levels, 850 to 1000mm and 1400 to 1600mm, contrasting visually with the background seen through the glass in all lighting conditions.
Glass doors must be clearly differentiated from any adjacent glazed wall or partition by the provision of a high-contrast strip at the top, and on both sides.
Fire doors, particularly those in corridors must be held open with an electro-magnetic device but self-close when:
- activated by smoke detectors linked to the door individually, or to a main fire/smoke alarm system.
- The power supply fails.
- Activated by a hand-operated switch.
Fire doors, particularly to individual rooms must be fitted with swing-free devices that close when activated by smoke detectors or the building’s fire alarm system, or when the power supply fails.
Corridors & Passageways
Corridors and passageways need to be wide enough to allow people on crutches to pass others on the access route. Wheelchair users should also have access to adjacent rooms and spaces, be able to pass other people and, where necessary, turn through 180°. Corridors narrower than indicated in this guidance or localised narrowing (e. g. at archways) might be reasonable in some locations such as in existing buildings or in some extensions.
In order to help people with visual impairment to appreciate the size of a space they have entered, or to find their way around, there should be a visual contrast between the wall and the ceiling, and between the wall and the floor. Such attention to surface finishes should be coupled with good natural and artificial lighting design.
Good acoustic design should be employed to achieve an acoustic environment that is neither too reverberant nor too absorbent so that announcements and conversations can be heard clearly.
Columns, radiators and fire hoses must not project into a corridor, where this is unavoidable a means of directing people around them, such as a visually contrasting guard rail should be provided.
Corridors must have an unobstructed width (excluding any projections into the space) along their length of at least 1200mm.
When a corridor has an unobstructed width of less than 1800mm, it has passing places at least 1800mm long and with an unobstructed width of at least 1800mm at reasonable intervals, e. g. at corridor junctions, to allow wheelchair users to pass each other.
The floor must be level or predominantly level (with a gradient no steeper than 1:60) with any section with a gradient of 1:20 or steeper designed as an internal ramp and must be in accordance with Table 1 and Diagram 3.
Where there is a section of the floor that has a gradient in the direction of travel steeper than 1:60 but less steep than 1:20, it must raise no more than 500mm without a level rest area at least 1500mm long (with a gradient no steeper than 1:60.
Any sloping section which extends the full width of the corridor or, if not, the exposed edge must be clearly identified by visual contrast and where necessary protected by guarding.
Any door opening towards a corridor which is a major access route or an escape route should be recessed so that when fully open it does not project into the corridor space, except where the doors are to minor utility facilities such as small store rooms and locked duct cupboards.
Any door for a unisex wheelchair-accessible toilet projects when open into a corridor that is not a major access route or an escape route is acceptable providing the corridor is at least 1800mm wide at that point.
On a major access route or an escape route the wider leaf of a series of double doors with leaves of unequal width must be on the same side of the corridor throughout the length of the corridor.
Floor surface finishes must not have patterns that could be mistaken for steps or changes in level. Floor finishes must be slip resistant.
Glazed screens alongside a corridor must be clearly defined with manifestation on the glass at two levels, 850 to 1000mm and 1400 to 1600mm, contrasting visually with the background seen through the glass in all lighting conditions.
It is worth noting that ramps are not necessarily safe and convenient for ambulant disabled people. For example some people who can walk but have restricted mobility find it more difficult to negotiate a ramp than a stair. Unless, therefore, a ramp is short, has a shallow gradient and the rise is no more than the minimum that can be provided by two risers, steps must be provided as well as a ramp.
Ramps must be readily apparent or the approach to a ramp must be clearly sign posted.
The gradient of a ramp flight and its going between landings must be in accordance with Table 1 and Diagram 3.
No flight must have a going greater than 10m or a rise of more than 500mm.
It must have a surface width between walls or upstands of at least 1.5m.
Intermediate landings at least 1800mm wide and 1800mm long are provided as passing places when it is not possible for a wheelchair user to see from one end of the ramp to the other or the ramp has three flights or more.
A handrail is required on both sides.
Where there is a change in level of 300mm or more, two or more clearly signposted steps must be provided in addition to a ramp.
Where there is a change in level no greater than 300mm, a ramp must be provided instead of a single step.
All landings must be level subject to a maximum gradient of 1:60 along their length.
The area beneath a ramp where the soffit is less than 2.1m above floor level must be protected by guarding and low level cane detection, or a permanent barrier giving the same degree of protection.
Handrails to internal steps, stairs and ramps
People who have physical difficulty in negotiating changes of level need the help of a handrail that can be gripped easily, is comfortable to tough and, preferably provides good forearm support.
Handrails should be set at heights that are convenient for all users of the building and should extend safely beyond the top and bottom of a flight of steps, or a ramp to give both stability and warning of the presence of a change in level.
The vertical height to the top of the upper handrail from the pitch line of the surface of a ramp, or a flight of steps is between 900mm and 1000mm and from the surface of a landing is between 900 and 1100mm.
Where there is full height structural guarding, the vertical height to the top of a second lower handrail from the pitch line of the surface of a ramp or a flight of steps is 600mm where provided.
It must be continuous across the flights and landings of ramped or stepped access.
It must extend at least 300mm horizontally beyond the top and bottom of a ramped access or the top and bottom nosing of a flight or flights of steps while not projecting into an access route.
It must contrast visually with the background against which it is seen without being highly reflective.
The surface of the rail must be slip resistant and not cold to touch.
The rail must terminate in a way that reduces the risk of clothing being caught.
The profile of the rail must be circular with a diameter between 40 and 45mm or oval preferably with a width of 50mm (see Diagram 7).
The rail must protrude no more than 100mm into the surface width of the ramped or stepped access where this would impinge on the stair width requirement.
There must be a clearance of between 60 and 75mm between the handrail and any adjacent wall surface.
There must be a clearance of at least 50mm between a cranked support and the underside of the handrail.
The inner face must be located no more than 50mm beyond the surface width of the ramped or stepped access.
Artificial lighting should be designed to give good colour rendering of all surfaces, without creating glare or pools of bright light and strong shadows. Where appropriate, lighting should illuminate the face of a person speaking to make lip reading easier where one-to-one communication is necessary. Uplighters mounted at low or floor level can disorientate some visually impaired people and should be avoided.
There are different categories of lighting available and a particular area where new lighting is required to come up to DDA compliant standards would need to be surveyed to interpret the level of lighting that would need to be put in place.