How do I break a while loop after a brick has stopped touching a part?

HitBox.Touched:connect(function() Touching = true end) HitBox.TouchEnded:connect(function() Touching = false end

Touching.Changed:connect(function()

end)

while Touching = true do insert script here end

I would suggest a game logic strategy for updating all queuing humanoids every so often. That way there's no need to worry about disconnecting and reconnecting events at an unnecessarily high rate, or breaking loops. Here's my personal tested solution to your problem...

--[[
    # Author: William J. Horn (ScriptGuider)
    # Contact: [email protected]

    # Efficiency test logs:
        test 1: 1    --   1.5%  CPU usage
        test 2: 0.4% --   1%    CPU usage
        test 3: 0    --   0.3%  CPU usage
--]]

-- Tested in an empty place using the baseplate as the part
local part = workspace:WaitForChild("Baseplate")
local tableRemove = table.remove

local function removeFromQueue(queue, key)
    for i = 1, #queue do
        if queue[i] == key then
            tableRemove(queue, i)
        end
    end
end

local function isInQueue(queue, key)
    for i = 1, #queue do
        if queue[i] == key then
            return true
        end
    end
end

local function addToQueue(queue, entry)
    queue[#queue + 1] = entry
end

local damageQueue = setmetatable({}, {
    __index = {
        add = function(self, human, hit)
            local entry = self:get(human)
            if entry and not isInQueue(entry[1], hit) then
                addToQueue(entry[1], hit)
            elseif not entry then
                addToQueue(self, {{hit}, human})
            end
        end,
        get = function(self, human)
            for i = 1, #self do
                if self[i][2] == human then
                    return self[i]
                end
            end
        end,
        remove = function(self, human, hit)
            local entry = self:get(human)
            if entry then
                removeFromQueue(entry[1], hit)
                if #entry[1] == 0 then
                    for i = 1, #self do
                        if self[i][2] == human then
                            tableRemove(self, i)
                        end
                    end
                end
            end
        end,
        step = function(self, damage)
            for i = 1, #self do
                local human = self[i][2]
                if human.Health > 0 then
                    self[i][2]:TakeDamage(damage)
                end
            end
        end
    }
})

part.Touched:Connect(function(hit)
    local human = hit.Parent:FindFirstChildOfClass("Humanoid")
    if human then 
        damageQueue:add(human, hit) 
    end
end)

part.TouchEnded:Connect(function(hit)
    local human = hit.Parent:FindFirstChildOfClass("Humanoid")
    if human then 
        damageQueue:remove(human, hit) 
    end
end)

-- Game logic
while wait(0.1) do
    -- damage queue step update dealing 1 damage
    damageQueue:step(1)
end

If you have any questions, just let me know.

HitBox.Touched:connect(function()
    while Mode.Value == "Gas" and Enabled.Value do
        for _, Brick in pairs (HitBox:GetTouchingParts()) do
            if Brick.Name == "Torso" and Brick.Parent:FindFirstChild("Humanoid") then
                Brick.Parent.Humanoid.Health = Brick.Parent.Humanoid.Health - 1
            end
        end
        wait (0.1)
    end
end)