Grade 9 Pre Tech Studies Study Notes

Foundations of Pre-Technical Studies

This strand introduces the basic concepts and skills you need to succeed in technical fields. It is the first strand in Pre-Technical Studies and lays the groundwork for everything else you will learn.

What this strand covers

• Sub-strand 1.1 — Safety on raised platforms: how to identify and use raised platforms safely.
• Sub-strand 1.2 — Handling hazardous substances: how to identify and safely manage dangerous materials.
• Sub-strand 1.3 — Self-exploration and career development: how to discover your talents and plan a career.

These topics connect directly to real work in construction, workshops, farms, laboratories, and offices.

What is a Raised Platform?

A raised platform is a structure or piece of equipment used to provide safe access for people, materials, or equipment to a higher area. Raised platforms can be fixed (permanently in one position) or adjustable (set up and moved as needed).

Without raised platforms, many everyday tasks would be impossible — a painter could not reach an upper wall, a librarian could not access a high shelf, and a speaker addressing a large crowd could not be seen from the back.

Types of Raised Platforms

1. Ladders

A ladder is a vertical or inclined set of steps used for climbing or descending safely and efficiently. The steps on a ladder are called rungs. A ladder must lean against a wall or structure — it cannot stand on its own.

Ladders are used at construction sites, warehouses, and homes.

2. Trestles

A trestle is a raised platform with two pairs of sloping legs that hold up a horizontal beam across the top. A wooden plank or board is laid across the top beam for the worker to stand on. Trestles are made of wood or metal.

Trestles are used in construction (bricklaying and plastering), carpentry, and painting.

3. Steps

Steps are self-supporting, ladder-like structures made of wood or fabricated steel. Unlike a ladder, steps do not need to lean against anything — they stand on their own. Steps can be fixed or portable.

Steps are used for maintenance work, painting, and order-picking in a warehouse. Because they are self-supporting, they give the worker the freedom to pick up and put down items such as tools without losing balance.

4. Stands

Stands are flat, raised structures made of wood, metal, or composite materials. They provide a firm, elevated surface for a worker to stand on directly. Unlike trestles, which support a beam along a wall, a stand provides a flat open surface the worker stands on directly.

Stands are used for painting, maintenance, and construction work. They also serve as elevated stages for speakers at public gatherings.

5. Workbenches

A workbench is a stable surface used for manual or mechanical tasks such as cutting, drilling, or machining. The worker stands on the ground beside the workbench — not on top of it — making it different from all other raised platforms.

Workbenches have two key safety features:

• A non-slip surface to reduce the risk of accidents.
• Clamps or vices to hold materials securely while cutting or drilling.

6. Ramps

Ramps are sloped surfaces that connect two levels of different heights. They are found inside and outside buildings and can be made of metal, reinforced concrete, or a combination of materials. Ramps provide an alternative to stairs for wheelchair users and people with bicycles or other wheeled items.

Learn More: Scaffolds

A scaffold is a temporary structure made of a timber or steel framework, used to support workers and materials during construction or repair. Once the work is done, the scaffold is taken down.

Scaffolds are usually built from steel or aluminium alloy tubes clipped together. They can also be made from wooden poles, timber, or bamboo.

Raised Platforms — Quick Comparison

Risks Associated with Working on Raised Platforms

A risk is the possibility that something harmful will happen. Raised platforms lift workers above the ground. Any mistake or fault at that height can cause serious injury. Knowing the risks is the first step to avoiding them.

There are five common risks when working on raised platforms.

Risk 1: Electrocution

Electrocution means being struck and injured — or killed — by an electric current. Working on a raised platform near an overhead power line or electrical equipment puts the worker dangerously close to live cables. If a metal scaffold or ladder touches or comes too close to a power line, current travels through the platform and through the worker's body.

Risk 2: Falls and Injuries Due to Weak and Worn-Out Platforms

A platform becomes weak and worn out when it has been damaged or has deteriorated over time — cracked rungs, split wood, corroded metal, or loose joints. The material gives way suddenly under the worker's weight — the platform does not bend first; it breaks without warning, causing the worker to fall and get injured.

Risk 3: Falls Due to Slippery Platforms

A platform becomes slippery when its surface gets wet from rain, spills, oil, or mud. Wet steps or ramps can cause a worker to slip and fall without warning. This risk is highest during rainy weather or in workplaces where liquids are used.

Risk 4: Falls and Injuries Due to Unstable Platforms or Uneven Ground

A platform is unstable when it is placed on uneven ground — soft soil, a slope, or loose gravel. This causes the platform to rock, sink, or tip. An unstable ladder can topple sideways, throwing the worker off.

Risk 5: Accidents Due to Overloading

Every raised platform is designed to hold a maximum weight. When too many people stand on one platform at the same time, or materials are piled beyond the limit, the platform can collapse — or suffer structural failure, where joints or the frame break apart.

Knowing these risks should change how you approach any raised platform — at school, at home, or in a future workplace. A few seconds of caution before stepping up can prevent a serious injury.

Observing Safety when Working on Raised Platforms

Minimising a risk means taking deliberate steps to reduce the chance that harm will occur. The book gives eight ways to minimise risks when working on raised platforms.

1. Proper Training

Proper training means teaching users of raised platforms the correct safety procedures — how to set up, use, and store each type of platform. In practice, a trained worker checks the platform before use, selects the correct PPE, sets up on level ground, and stops work when conditions become unsafe — all steps an untrained worker may skip.

2. Regular Inspections

Regular inspections mean checking a raised platform for signs of damage, wear and tear, or structural weaknesses before it is used. Faulty platforms must be repaired promptly or replaced — never used while damaged.

3. Use of Appropriate Equipment

Always use appropriate protective equipment when working on raised platforms. This includes Personal Protective Equipment (PPE) such as helmets and gloves. PPE does not prevent a fall, but it reduces the severity of injuries if something goes wrong.

4. Correct Choice of Platform

Always use the most appropriate platform for the specific task. Using the wrong platform increases risk — for example, standing on a workbench to reach a high ceiling when a ladder is needed. Each platform is designed for certain tasks.

5. Observe Weight Limits and Load Capacity

Every raised platform has a weight limit — the maximum it can safely hold. Load capacity is the total weight of people, tools, and materials the platform can carry at once. Weight limits are usually marked on the platform itself or provided in the safety guidelines. Exceeding the limit can cause collapse or structural failure.

6. Stable Base and Level Surface

Raised platforms must be set up on a stable base and a level surface to prevent tipping or instability. Soft soil, a slope, or loose gravel will cause the platform to shift or sink unevenly.

7. Always Consider the Weather

Monitor weather conditions and avoid working on raised platforms during strong winds, heavy rain, or icy conditions. Strong winds can topple a ladder or trestle. Rain makes surfaces slippery. Ice makes every step dangerous.

8. Regular Maintenance and Repair

Regular maintenance and repair means keeping raised platforms in good working condition at all times — not just fixing problems after they appear, but routinely checking and servicing them. A well-maintained platform lasts longer and is less likely to fail without warning.

Safety training and protocols exist because every risk in this sub-strand has caused real injuries. Following them is not a formality — it is a habit that protects you and everyone working around you.

Observing Safety when Working on Raised Platforms (continued)

The eight ways to minimise risks are general principles. In real work, you apply them to specific situations. Practise these precautions by role-playing each scenario — reading them is only the first step.

Scenario 1: A Firefighter Climbing a Ladder

• Wear full protective gear — helmet, heat-resistant gloves, safety boots.
• Confirm the ladder is firmly positioned on flat, non-slippery ground.
• Ensure the ladder leans at the correct angle — not too steep, not too flat.
• Have a colleague steady the base while climbing.

Scenario 2: A Mason on a Trestle

• Place the trestle on a level, firm surface.
• Check the trestle is not overloaded with tools or materials.
• Ensure the plank is secured so it cannot slide or shift.
• Wear a helmet and safety boots.

Scenario 3: A Librarian on a Step

• Make sure steps are fully open and locked before standing on them.
• Do not over-reach sideways — step down and reposition if a book is out of easy reach.
• Wear non-slip footwear.
• Place steps on a flat, dry floor.

Scenario 4: An Electrician on a Trestle

• Switch off the electricity supply before starting any work.
• Confirm the trestle is stable and on level ground.
• Wear insulated gloves to protect against remaining current.
• Ensure no one stands directly below while work is in progress.

Safety Tip: No Furniture as Raised Platforms

Do not use furniture such as stools as raised platforms. Stools can tip or break under load, causing injuries. A stool has no load rating, no non-slip base, and no stability at height. Always use a purpose-built platform.

Responsibility for workplace safety belongs to everyone — including you. Always check your platform, use it correctly, and stop if something is unsafe.

Observing Safety when Working on Raised Platforms (continued)

Why Regular Inspections are Important

Regular inspection means checking a raised platform for damage, wear and tear, and structural weaknesses before every use — not just once a week or when something looks wrong. A platform can be damaged between one use and the next, and hidden damage can cause sudden failure under a worker's weight.

Faulty platforms must be repaired promptly or replaced before anyone steps on them.

Personal Protective Equipment (PPE)

Personal Protective Equipment (PPE) is clothing and gear that protects specific parts of the worker's body from injury. Different tasks require different PPE. You are also responsible for your PPE — check it before use. Damaged PPE must be reported and replaced — it cannot protect you if it is broken or torn.

Overalls

Overalls are full-body suits worn over clothing. They protect the whole body from dust, chemical splashes, paint, and contact with rough surfaces.

Gas Mask

A gas mask covers the nose and mouth and filters out harmful gases, fumes, dust, or chemical vapours. Used when spraying paint, working with chemicals, or in poorly ventilated spaces.

Gloves

Gloves protect the hands from cuts, heat, chemicals, and electrical hazards. The type of glove depends on the task — leather for rough materials, rubber for electrical work, chemical-resistant for hazardous substances.

Apron

An apron is worn over overalls to protect the front of the body from spills, splashes, heat, and physical contact during tasks involving liquids, chemicals, or hot materials.

Safety Boots and Gumboots

Safety boots and gumboots protect the feet from falling objects and sharp materials. They have reinforced toe caps and non-slip soles to prevent slipping on wet or uneven surfaces.

Safety Glasses and Goggles

Safety glasses and goggles protect the eyes from dust, flying chips, chemical splashes, and debris. Worn during cutting, drilling, grinding, or any task that sends particles or liquid into the air.

Face Shields

A face shield covers the entire face — eyes, nose, mouth, and chin — from splashes, sparks, and flying particles. It gives fuller protection than safety glasses and is used for more hazardous tasks.