1.1.9 Scaffolds

Scaffolding has a variety of applications. It is used in new construction, alteration, routine maintenance, renovation, painting, repairing, and removal activities. Scaffolding offers a safer and more comfortable work arrangement compared to leaning over edges, stretching overhead, and working from ladders. Scaffolding provides employees safe access to work locations, level and stable working platforms, and temporary storage for tools and materials for performing immediate tasks. Scaffolding accidents mainly involve personnel falls and falling materials caused by equipment failure, incorrect operating procedures, and environmental conditions. Additionally, scaffolding overloading is a frequent single cause of major scaffold failure. This safety policy and procedure provides guidelines for the safe use of scaffolds. It includes training provisions and guidelines for scaffold erection and use.

Policy

Scaffolds shall be erected, moved, dismantled, or altered only under the supervision of a competent person and will have guardrails and toeboards installed. When scaffolding hazards exist that cannot be eliminated, then engineering practices, administrative practices, safe work practices, Personal Protective Equipment (PPE), and proper training regarding Scaffolds will be implemented. These measures will be implemented to minimize those hazards to ensure the safety of employees and the public.

Definitions

  • Brace: A tie that holds one scaffold member in a fixed position with respect to another member. Brace also means a rigid type of connection holding a scaffold to a building or structure.
  • Coupler: A device for locking together the component tubes of a tube and coupler scaffold
  • Harness: A design of straps which is secured about the employee in a manner to distribute the arresting forces over at least the thighs, shoulders, and pelvis, with provisions for attaching a lanyard, lifeline, or deceleration device
  • Maximum Intended Load: The total load of all employee, equipment, tool, materials, transmitted, wind, and other loads reasonably anticipated to be applied to a scaffold or scaffold component at any one time
  • Outriggers: The structural member of a supported scaffold used to increase the base width of a scaffold in order to provide greater stability for the scaffold
  • Platform: The horizontal working surface of a scaffold
  • Safety Belt: A strap with means for securing about the waist or body and for attaching to a lanyard, lifeline, or deceleration device
  • Scaffold: Any temporary elevated or suspended platform and its supporting structure used for supporting employees or materials or both, except this term does not include crane or derrick suspended personnel platforms

Safe Scaffold Erection and Use

Safe scaffold erection and use is important in minimizing and controlling the hazards associated with their use. Scaffold work practices and rules should be based on:

  • Sound design
  • Selecting the right scaffold for the job
  • Assigning personnel
  • Fall protection
  • Guidelines for proper erection
  • Guidelines for use
  • Guidelines for alteration and dismantling
  • Inspections
  • Maintenance and storage

Types of Scaffolds

There are many different types of scaffolds used and the type of work will determine which type to select. The three major categories are:

  • Self-supporting scaffolds
  • Suspension scaffolds
  • Special use scaffolds

Self-supporting scaffolds are one or more working platforms supported from below by outriggers, brackets, poles, legs, uprights, posts, frames, or similar supports. The types of self-supporting scaffolds include:

  • Fabricated Frame
  • Tube and Coupler
  • Mobile
  • Pole

Suspension scaffolds are one or more working platforms suspended by ropes or other means from overhead structures(s). The types of suspension scaffolds include:

  • Single-Point Adjustable (Boatswain’s Chairs)
  • Two-Point Adjustable (Swing Stage)
  • Multiple-Point Adjustable
  • Multi-Lend
  • Category
  • Float (Ship)
  • Interior Hung
  • Needle Beam

Special use scaffolds and assemblies are capable of supporting their own weight and at least 4 times the maximum intended load. The types of special use scaffolds include:

  • Form and carpenter bracket
  • Roof bracket
  • Outrigger
  • Pump jack
  • Ladder jack
  • Window jack
  • Horse
  • Crawling boards
  • Step, platforms, and trestle ladder

Responsibilities

  • Competent Person – The competent person will oversee the scaffold selection, erection, use, movement, alteration, dismantling, maintenance, and inspection. The competent person will be knowledgeable about proper selection, care, and use of the fall protection equipment. Additionally, the competent person shall assess hazards.
  • Employees – Employees shall comply with all applicable guidelines contained in this safety policy and procedure. Employees will report damaged scaffolds, accessories, and missing or lost components. Employees will assist with inspections as requested.
  • Safety Department – Safety staff will provide prompt assistance to managers/unit heads, supervisors, or others as necessary on any matter concerning this safety policy and procedure. Safety staff will assist in developing or securing required training. Safety staff will also work with engineering and technical staff to ensure that all newly purchased scaffolds comply with current safety regulations and the organisation’s safety policy and procedure. Safety staff will provide consultative and audit assistance to ensure effective implementation of this safety policy and procedure.
  • Purchasing Department – Purchasing department is responsible for ensuring that purchased scaffolds and related material and equipment are procured as specified by engineering and/or technical staff and that delivered items meet or exceed current safety regulations.

The above precautions also apply when organisations use external scaffolding suppliers for a particular task.

Safety Requirements for Scaffolds

Government Notice R: 1031 of 30 May 1986, General Safety Regulations, 1986 states that:

Boatswain’s Chairs

13C.  An employer shall ensure that every boatswain’s chair or similar device is securely suspended and is so constructed as to prevent any occupant from falling therefrom.

Scaffold framework

13D.(1)  An employer shall ensure that –

(a)  Scaffold standards are properly propped against displacement and are secured vertically on firm foundations: Provided that putlog scaffolds shall incline slightly towards the structure;

(b)      (i)  steel scaffold standards with ‘heavy’, ‘medium’, ‘light’, or ‘very light’, platform loadings which shall not exceed 320, 240, 160 and 80 kg/m2 respectively, are spaced not more than 1.8 m, 2 m, 2.5 m and 3 m apart, respectively; and

(ii)  wooden scaffold standards are spaced not more than 3 m apart;

(c)  ladders are spaced vertically not more than 2.1 m apart;

(d)  putlogs or transoms —

(i)  which do not support a platform, are spaced at the same distances as the distances prescribed in paragraph (b) in respect of scaffold standards.

(ii)  which support a platform, are spaced not more than 1.25 m apart if the platform is constructed of solid timber boards; and

(e)  every part of a wooden scaffold frame has a diameter of at least 75 mm or a section of similar strength.

(2)  No employer shall use a scaffold, or permit it to be used unless it –

(a)  is securely and effectively braced to ensure stability in all directions;

(b)  is secured at suitable vertical and horizontal distances to the structure to which work is being done, unless it is designed to be completely free-standing;

(c)  is so constructed that it has a throughout factor of safety of at least two; and

(d)  is inspected at least once a week and every time after bad weather by a person who has adequate experience in the erection and maintenance of scaffolds, and all findings are recorded in a register or report book.

(3)  No employer shall require or permit that –

(a)  a scaffold with a supporting wooden framework exceeds a height of 10 m; and

(b)  a scaffold is erected, altered or dismantled by or under the supervision of a person other than a person who has had the necessary training and experience of such work and who has been appointed by the employer in writing for this purpose.

Scaffold platforms

 13E.(1)  An employer shall ensure that –

(a)  every plank of a solid wooden scaffold platform is at least 275 mm wide and 38 mm thick;

(b)  every plank which forms part of a scaffold platform is supported at distances not exceeding 1.25 m, and its ends are projected not less than 70 mm and not more than 200 mm beyond the last prop;

(c)  every plank of a scaffold platform is firmly secured to prevent its displacement; and

(d)  every platform is so constructed as to prevent materials and tools from falling through.

(2)  An employer shall ensure that every scaffold platform-

(a)  with ‘heavy’ ‘medium’, ‘light’ or ‘very light’ platform loadings as referred to in regulation 13D (1) (b) (i) is not less than 1 125 mm and not more than 1 380 mm, not less than 1 125 mm and not more than 1 150 mm, not less than 900 mm and not more than 1 150 mm, and not less than 675 mm and not more than 1 150 mm, respectively, wide: Provided that where a platform is used only as a gangway, a platform width of 450 mm shall be sufficient;

(b)  which is more than 2 m above the ground is on all sides, except the side facing the structure, provided with-

(i)  substantial guard rails of at least 900 mm and not exceeding 1 000 mm in height; and

(ii)  toe-boards which are at least 150 mm high from the level of the scaffold platform and so affixed that no open space exists between the toe-boards and the scaffold platform: Provided that if the toe-boards are constructed of timber, they shall be at least 25 mm thick;

(c)  is not more than 75 mm from the structure: Provided that where workmen must sit to work, this distance may be increased to not more than 300 mm; and

(d)  is kept free of waste, projecting nails or any other obstructions, and is kept in a non-slip state.

(3)  No employer shall require or permit that a working platform which is higher than 600 mm be supported on a scaffold platform, and shall provide an additional guard rail of at least 900 mm and not exceeding 1000 mm in height above every such working platform.

(4)  An employer shall ensure that convenient and safe access is provided to every scaffold platform, and where the access is a ladder, the ladder shall project at least 900 mm beyond the top of the platform.

Suspended scaffolds

13F. (1)  An employer shall ensure that the outriggers of each suspended scaffold –

(a)  are constructed of steel or any other material of similar strength and have a factor of safety of at least four with respect to the load it is to carry;

(b)  have an overhang of not more than 1.8 m beyond the edge of the structure and are of such length that the counteracting length can be anchored securely:

(c)  are, otherwise than by means of weights at the inner-ends, properly propped, suitably spaced and firmly anchored: Provided that an inspector may grant permission that outriggers may be anchored by means of weights; and

(d)  are provided with stop or other effective devices at the outer-ends to prevent the displacement of ropes.

(2)  An employer shall ensure that the working platform of every suspended scaffold is suspended by:

(a)  pulley-blocks, sheaves, winches or hoists of the correct size for the ropes being used;

(b)  at least two independent steel wire ropes in the case of a working platform which is not wider than 912 mm, and at least four independent steel wire ropes in the case of a working platform which is 912 mm and wider; and

(c)  steel wire ropes of which the factor of safety is at least ten with respect to the maximum load which each rope is to carry.

(3)  An employer shall ensure that –

(a)  the hand or power-driven machinery used for the lifting or lowering of the working platform of a suspended scaffold is so constructed and maintained that an uncontrolled movement of the working platform cannot occur;

(b)  the machinery referred to in paragraph (a) is so situated that it is easily accessible for inspection;

(c)  the rope connections to the outriggers are vertically above the connections to the working platform; and

(d)  in the case of a working platform suspended by two ropes only, the connections of the ropes to the working platform are of such height above the level of the working platform as to ensure the stability of the working platform.

(4)  An employer shall ensure that the working platform of every suspended scaffold –

(a)  is at least 456 mm and not exceeding 1.8 m in width;

(b)  is suspended as near as possible to the structure to which work is being done and, except when light work is being done, is secured at every working position to prevent horizontal movement between the working platform and the structure;

(c)  is on all sides, except the side facing the structure, provided with substantial guard rails of at least 900 mm and not exceeding 1000 mm in height above the level of the working platform: Provided that in the case of a working platform suspended by two ropes only, the guard rails shall be on all sides; and

(d)  is on an sides provided with toe-boards which are at least 150 mm high from the level of the working platform and so affixed that no open space exists between the toe-boards and the working platform: Provided that if the toe-boards are constructed of timber, they shall be at least 25 mm thick.

Trestle scaffolds

13G.(1)  No employer shall use a trestle scaffold, or permit it to be used, unless –

(a)  it is soundly constructed of solid material, and

(b)  all reasonable precautionary measures have been taken to prevent the unexpected spreading of its supporting legs when it is in use.

(2)  No employer shall use a trestle scaffold or permit it to be used, if it –

(a)  is higher than 3 m; or

(b)  consists of more than two tiers.

Safety Precautions