LowHealthEffect

local player = game.Players.LocalPlayer
local character = script.Parent
local humanoid = character:FindFirstChild("Humanoid")
local sound = player.PlayerGui:FindFirstChild("LowHealthSound")

while wait() do
    if humanoid.Health <= 40 then
        if sound.Playing == false then
            sound:Play()
        end
    else
        if sound.Playing == true then
            sound:Stop()
        end
    end
end