Safety in PV Installation – SS2 Solar Photovoltaic Installation & Maintenance Lesson Note (First Term)

Safety in solar PV installation is the set of practices that protect installers from falls, electric shock and heat while they fit and maintain solar systems.

Behavioural objectives

By the end of the lesson, students should be able to:

1. state the three main dangers in solar installation;
2. list the essential personal protective equipment (PPE) and give the purpose of each item;
3. describe how to check, fit and anchor a safety harness and how to use a ladder safely;
4. identify common site hazards during a site walkthrough;
5. state the safe handling rules for working on live panels and inverters;
6. state what to do when a teammate receives an electric shock.

What are the dangers in solar PV installation?

There are three main dangers in solar PV installation: falls from height, electric shock and heat.

• Gravity (falls): installers work high up on roofs, and one slip can cause serious injury or death.
• Electricity: panels produce power whenever there is light, so the wires are live during the day.
• Heat: roofs and panels become very hot, and heatstroke or exhaustion can cause dizziness and falls.
• Heavy panels: a panel is awkward to carry and can cause back injury or a fall if dropped.

What is the safety goal?

• Zero accidents: this is the aim of every installation team.
• Right gear: every person wears the correct PPE before going on the roof.
• Site check: the site is inspected before the first panel is lifted.

What is personal protective equipment (PPE)?

Personal protective equipment (PPE) is the clothing and gear a worker wears to reduce injury if something goes wrong.

• Last line of defence: PPE protects you after other safety steps have failed, so it does not replace them.

What are the essential PPE items?

• Safety helmet (hard hat): protects the head from falling tools and from bumps against steel frames.
• Rubber-soled boots: give grip on a slippery roof and help insulate against electric shock.
• Reflective vest: lets teammates and ladder or crane operators see where you are.
• Safety gloves: protect the hands from sharp aluminium panel edges.
• Insulated gloves: protect against electric shock when handling live DC wiring.
• Eye protection: stops dust and metal chips from entering the eyes when drilling walls or frames.

How do you work safely at heights?

Working safely at heights means using a harness, a secure anchor and a properly set ladder every time you leave the ground.

• Harness rule: use a safety harness whenever you work at height on a roof, as most site rules require.
• Height limit: many site rules set the limit at about 2 metres, but follow your employer’s rule.

How do you use a safety harness properly?

1. Inspect it: check the straps, stitching and buckles for frays, cuts and tears before every use.
2. Fit it: adjust it so it is snug and no strap hangs loose, following the maker’s instructions.
3. Choose an anchor point: attach to a solid part of the building structure, never a plastic pipe or weak wooden beam.
4. Clip on: connect the lanyard to the anchor before you move onto the roof, and stay connected while you work.

How do you use a ladder safely?

• Buddy: have a teammate hold the base of the ladder.
• Firm ground: place the ladder on level, solid ground.
• Angle: set the foot one unit out for every four units of height (the 1 in 4 rule).
• Top rung: never stand on the top rung, because you can lose your balance.
• Three points of contact: keep two hands and one foot, or two feet and one hand, on the ladder when climbing.
• Material: keep a metal ladder well away from power lines.

How do you identify site hazards?

A site hazard is anything at the work place that can cause injury, and the team lead finds them in a site walkthrough before work starts.

What hazards should you look for?

• Overhead power lines: a metal ladder or long panel touching a line can cause electrocution, so keep a safe distance.
• Weak roofs: old asbestos or rusted zinc sheets can crack under a person’s weight.
• Weather: come down at once if it drizzles or the wind rises, because a panel acts like a sail.
• Tripping hazards: loose wires and tools on a cramped roof can cause a fall.
• Roof edges: open edges and gaps need to be marked or guarded.

How do you stand on a weak roof?

• Step on purlins: purlins are the wooden or metal supports under the sheets, so step only where they are.
• Use boards: spread your weight if the team lead says the sheets are fragile.

How do you prevent heat illness?

Heat illness is sickness caused by working too long in strong sun without water or rest.

• Drink water: sip water often during the job.
• Take breaks: rest in the shade away from the roof edge.
• Start early: do the roof work in the cooler morning hours where possible.
• Cover up: wear light clothing that covers the skin.
• Warning signs: dizziness, headache and heavy sweating mean you should stop and come down.

What are the electrical safety rules for a live panel?

A live panel is a solar panel that produces voltage whenever light falls on it, and it cannot be switched off.

What are the safe handling rules?

1. Cover the panels: an opaque cover, such as a dark cloth, lowers the output while wiring a high-voltage string. Still treat the wires as live.
2. Isolate before work: before working on the inverter, disconnect the battery, the grid and the DC isolator.
3. Lock-Out Tag-Out (LOTO): lock the switches and attach a tag so nobody switches them on while you work.
4. The “one hand” rule: when testing live wires with a meter, keep the other hand away from metal and from your body. This helps stop current passing across the chest.
5. Insulated tools: use tools with insulated handles and keep your hands dry.

What should you do if a teammate gets an electric shock?

If a teammate gets an electric shock, do not touch them with bare hands, because the current can pass to you.

1. Shout for help: alert the team lead and others on site.
2. Break contact: use a dry wooden stick or plastic pipe to push the person away from the wire.
3. Isolate: switch off or disconnect the source only if it is quick and safe to do so.
4. Call for medical help: contact emergency services or the nearest clinic at once.
5. Give first aid: if you are trained, check breathing and start CPR if needed.

Evaluation

1. Name the three major dangers in solar installation.
2. Give two reasons why rubber-soled boots are part of the PPE.
3. At what height must you use a safety harness, and what three steps make sure you use it properly?
4. List four hazards to look for during a site walkthrough.
5. What should you do if a teammate gets an electric shock?

Assignment

Write a short safety checklist for a roof installation team. Include the PPE items, the harness checks, four site hazards and two electrical safety rules from this lesson.